CN106133624A

CN106133624A - Reduce the controller controlled in loop to update

Info

Publication number: CN106133624A
Application number: CN201580015134.3A
Authority: CN
Inventors: T·L·布莱文斯; M·J·尼克松; K·K·詹森; M·S·潘瑟; D·陈; E·罗特沃尔德
Original assignee: Fisher Rosemount Systems Inc
Current assignee: Fisher Rosemount Systems Inc
Priority date: 2014-03-20
Filing date: 2015-03-20
Publication date: 2016-11-16
Anticipated expiration: 2035-03-20
Also published as: GB2543156A; JP2017516190A; GB2587576A; JP6835589B2; GB201615542D0; CN109976144A; DE112015001348T5; GB202020175D0; WO2015143298A1; CN109976144B; CN106133624B; GB2543156B; GB2587576B

Abstract

A kind of technology that controls controls process in the way of reducing the quantity of the controller change being supplied to controlled plant, thus reduces the power consumption of controlled plant and the load of process control communication network being arranged between controller and controlled plant.This technology is highly useful in the control system have the field apparatus of wireless connections of such as sensor and valve, and sensor and valve operate with battery electric power in many cases.In addition, this control technology is in implementing the control signal control system by the communication of interval, asynchronous or notable delay, and/or is useful in the process variable of reception interval, asynchronous or notable delay is measured for use as the control system of the feedback signal in the realization of closed loop control.

Description

Reduce the controller controlled in loop to update

Related application

The application is the application of regular submission, it is desirable in the entitled " Reducing that on March 20th, 2014 submits to Controller Updates in a Control Loop " U.S. Provisional Patent Application Serial No. 61/968,159 preferential Power, during the entire disclosure is expressly incorporated herein thereby through reference.The application still submits on January 17th, 2012 Entitled " Compensating for Setpoint Changes in a Non-Periodically Updated Controller " the part continuation application of U.S. Patent Application Serial Number 13/351,802, the entire disclosure is so as to logical In crossing with reference to being expressly incorporated herein.The application further relates in the entitled " Wireless of JIUYUE in 2007 submission on the 6th Communication of Process Measurements " U.S. Patent Application Serial Number 11/850,810, No.11/ 850,810 is entitled " the Process Control With Unreliable submitted on August 4th, 2006 Communications " U.S. Patent Application Serial Number 11/499,013 and be issued as the portion of United States Patent (USP) No.7,620,460 Dividing continuation application, No.7,620,460 is entitled " the Non-periodic Control submitted on October 25th, 2005 Communications in Wireless and Other Process Control Systems " U.S. Patent application sequence Row No.11/258,676 and be issued as United States Patent (USP) No.7, the part continuation application of 587,252, each of which whole During disclosure is expressly incorporated herein thereby through reference.

Technical field

This patent relates to implementing to control, specifically in the control loop with slow, interval or acyclic communication For, relate to control routine, its in the way of reducing the quantity that the controller being supplied to controlled plant updates controlling in loop Use non-periodic signals transmits.

Background technology

The Process Control System of the most distributed or scalable formula Process Control System, as chemistry, oil or other During, typically comprising one or more process controller, the analog/digital bus via simulation, numeral or combination can Be communicably coupled to each other, at least one main frame or operator workstation and one or more field apparatus.Field apparatus is such as Can be valve, valve positioner, switch and transmitter (such as temperature, pressure, flow sensor), perform such as to beat in process Open or close the function of valve closing door and measurement process parameters.Process controller receives and represents the process measurement made by field apparatus And/or the signal of other information relevant with field apparatus, and this information is used to control letter to implement control routine to generate Number, control signal is sent to field apparatus to control the operation of process by circuit or bus.From field apparatus and control The information of device typically can be used for the one or more application performed by operator workstation, so that operator is able to carry out phase For any desired function of process, such as, check the current state of process, the operation etc. of amendment process.

Some Process Control Systems, the DeltaV that such as Emerson Process Management sells^TMSystem, uses The functional device being referred to as module being positioned in controller or different field apparatus or the group of functional device are to perform control and/or monitoring Operation.In these cases, controller or other equipment can include and perform one or more functional device or module, and it is each Individual all reception from other functional devices inputs and/or provides output to other functional devices (in same equipment or at distinct device In), and perform some process operations, such as measure or detect procedure parameter, monitoring device, control equipment or perform to control behaviour Make, the such as enforcement of PID (PID) control routine.Difference in functionality block and module in Process Control System are usual It is configured to communicate with one another (such as passing through bus) to form one or more process control loop.

Process controller is typically programmed to carry out algorithms of different, subroutine or control loop, and (they are all to control example Journey), for for process definition or each of multiple different circuits of comprising in process, such as flow control circuit, temperature Control loop, pressure control loop etc..In general, each such control loop includes one or more input block, as Analog input (AI) functional device, one or more control blocks, such as PID (PID) or fuzzy logic control function Block, and IOB, such as analog output (AO) functional device.The functional device of control routine and this routine of enforcement is according to multiple controls Technology configures, including PID control, fuzzy logic control and technology based on model, such as Smith Predictor or Model Predictive Control (MPC) (Model Predictive Control).

In order to support the execution of control routine, typical industry or processing factory have centralized control room, communicably with one Individual or multiple process controller and process i/o subsystem connect, and they are connected to one or more field apparatus.Traditionally, Analog field device is connected to controller by two wires or the four-wire current loops for signal transmission with supply of electric power.Simulation Field apparatus, such as sensor or send signal to the transmitter of controller, regulate the electric current of operation by current loop, So that electric current is directly proportional to the process variable sensed.On the other hand, the simulation performing operation under the control of the controller is existing Field device is controlled by by the size of the electric current in loop.The analog-and digital-field apparatus of many numerals or combination is by numeral The analog-and digital-communication network of communication network or combination receives or emission control or measure signal.

Along with the increase of volume of transmitted data, a particular importance of process control system design was included in program control In system processed or processing factory field apparatus be communicably coupled to each other, controller and other system or the mode of equipment.One In the case of as so that generally unite in various communication channels, link and path that field apparatus can run in Process Control System It is referred to as input/output (I/O) communication network.

Field apparatus is communicated with physical connection or path for implementing the communication network topology structure of I/O communication network Robustness or integrity there is substantial impact, especially when network is subjected to poor environment factor or harsh conditions. These factors and condition compromise the integrity of the communication between one or more field apparatus, controller etc..At controller With the communication between field apparatus is particularly sensitive for any this destruction, because monitoring application program or control routine are typically Need process variable periodically updating for the iteration each time of routine.Therefore impaired control communication can cause control system Efficiency and/or profitability reduce, for excessive wear or the damage of equipment, and any amount of potentially harmful fault.

In order to ensure the communication of robust, the I/O communication network in Process Control System is always hard-wired.Unfortunate , hard-wired network introduces many complexity, a difficult problem and restriction.Such as, the quality of hard-wired network can be in time Decline.Additionally, hard-wired I/O communication network is generally expensive installing, particularly I/O communication network be distributed in In the case of large scale industry factory on big region or facility are associated, such as, take oil plant or the chemical industry in several mu of soils Factory.Necessary long transmission line runs and is usually directed to a considerable amount of labour force, material and expense, and may introduce due to wiring impedance The signal degradation produced with electromagnetic interference.For these and other reasons, hard-wired I/O communication network is generally difficult to again Configure, revise or update.

Nearest trend is to use wireless I/O communication network to alleviate some difficulties relevant with hard-wired I/O network. Such as, entitled " Apparatus for Providing Redundant Wireless Access to Field Devices In a Distributed Control System " U.S. Patent Application Publication No.2003/0043052, its entire disclosure Content, thereby through with reference in being expressly incorporated herein, discloses a kind of system, utilizes radio communication to increase or supplements and firmly connects The use of the communication of line.

But especially because integrity problem, limited traditionally for controlling the dependence of the radio communication of relevant transmission System.As it has been described above, modern monitoring application program and process control application program depend on can between controller and field apparatus The data communication leaned on, to reach optimal control performance.Additionally, typical controller quickly performs control algolithm to correct rapidly During unnecessary deviation.Bad environmental factors or other unfavorable conditions can produce intermittent interference, and it hinders or stops Support quickly or periodically to communicate necessary to this execution of monitoring or control algolithm.Fortunately, at 10 years of the past In, wireless network becomes the most powerful so that can reliably use radio communication in some type of Process Control System.

But power consumption remains complicated factor when using radio communication in process control in applying.Owing to wireless field sets For disconnecting with I/O network physically, field apparatus typically needs to provide the power supply of their own.Therefore, field apparatus is permissible It is that battery is powered, drawn solar electrical energy generation or obtain environmental energy, such as vibration, heat, pressure etc..For these equipment, data pass Defeated consumed energy may be constructed sizable part of total energy consumption.It practice, with performed by field apparatus other are heavy The operating process wanted is compared, such as in order to sense or detect measured process variable institute steps taken, is setting up and dimension Hold and radio communication connection procedure can consume more power.In order to reduce power consumption in wireless process control system and thus Extending battery life, it is proposed that enforcement wireless process control system, wherein, the field apparatus of such as sensor is with aperiodicity Mode and controller communication.In a case, only in process variable being detected when significantly changing, field apparatus is just and control Device communication processed or process variable measurement is sent to controller, causes the aperiodicity communication with controller.

A kind of control technology developed to process non-periodic process variable measurement updaue uses control system, Its provide and maintain for by controller infrequently, the expection of control signal that produces between aperiodicity measurement updaue The instruction of journey response.The response of expection process can be by mathematical Model Development, and it calculates the control signal for given measurement updaue Expection process response.One example of this technology is at entitled " Non-Periodic Control Communications In Wireless and Other Process Control Systems " United States Patent (USP) No.7, illustrated in 587,252, During the entire disclosure is expressly incorporated herein thereby through reference.Specifically, which disclose a kind of control system, Having wave filter, it is after receiving non-periodic process variable measurement updaue, and the expection process for control signal that generates is rung The instruction answered, and maintain the instruction that the expection process of generation responds, until next non-periodic process variable measurement updaue arrives Reach.As another example, the U.S. of entitled " Process Control With Unreliable Communications " Patent No.7,620,460, during the entire disclosure is expressly incorporated herein thereby through reference, disclose a kind of system, bag Including wave filter, it provides the instruction of intended response for control signal, but revises this wave filter further to be incorporated to since The measurement of elapsed time after later aperiodicity measurement updaue, to generate the instruction of expection process response the most accurately.

But in past 5 years, the manufacturer of field instrument devices has been introduced into variousPick-up Device.Initially, these transmitters are only used for monitoring process.But according to the introduction of above-mentioned technology, can make in closed loop control is applied Use wireless measurement.Accepting extensively based on to wireless transmitter, many commercial cities that manufacture in exploitation and introduce wireless ON/OFF and throttling During valve.

But multiple technical barrier must be solved so as to use this wireless valve in closed loop control.Specifically, Typically, only have limited amount power at wireless valve can use, it is contemplated that these available horsepowers of major part are at target valve position When making a change necessary, such as in response to receiving control signal, valve is driven into its target location.But it is typical Control technology attempts many control signals are sent to controlled equipment, in order to guarantee the control performance of robust.But by these skills The battery resource at controlled plant is used up rapidly in a large amount of based on controller the mobile meeting that art is implemented.Therefore if it would be possible, Wish to reduce what the valve such as made in closed loop control process in response to the change in set point, process interference etc. moved Quantity.

Additionally, in many cases, control system operation can not be Tong Bus with gateway communication, gateway communication be at controller and Communication is provided to occur between wireless valve or setting other actuators within a wireless communication network.Such as, asThe current design of the radio network gateway of gateway can be to the change of valve location is sent to valve cause Action the most immediately after the request of dynamic device, thus valve or actuator can this control signal after controller generates considerably long Time receives control signal.Additionally, controller can longer after having been sent the change in valve location by controller time Between just receive from valve or actuator and confirm.Thus, in the case, target valve position (such as control signal) and valve ring The radio communication answered introduces sizable variable delay in controlling loop, and this delayed impact PID controls so that controlled change The robust control of amount is increasingly difficult.

Summary of the invention

Such as may be used for a kind of control technology in pid control circuit to significantly reduce from controller (such as PID control Device processed) amount of communications of elements is controlled to other in wireless valve or processing factory, still provide controlled process variable simultaneously Robust control.Thus, wireless valve or other control elements can use less power, because valve must be for target valve In door position, less change is made a response, and still provides acceptable robust control simultaneously.Additionally, at controller via entrance The gateway of wireless network is communicatively connected in the factory of controlled plant use this control technology can reduce gateway communication and bears Lotus, because this technology can cause less to wireless valve or the communication of other controlled members.It is permissible that this controls technology Use in conjunction with other intervals or acyclic control method, thus wireless transmitter and nothing can be used in controlling loop One or both of line valve (or other controlled in wireless elements) performs control.Additionally, this technology may be used for wired or Other periodicity control systems perform control to reduce unnecessary or invalid valve move, the most typically having noise The valve location that is subjected in control system swings, such as in the feedback including noise is measured or cause relatively at noise In random process interference.

It addition, new control signal order may be used for via the wireless or aperiodicity of other intervals or asynchronous communication network Network sends control signal, in order to contribute to the control performance of control technology as herein described.New controller signals can include Desired value and the time of implementation goal value.This command signal or other signals allow more precisely to calculate implicit at controller Valve location, thus may be used for process control loop communication (such as set with the controlled of such as valve at process controller Between Bei) in system by notable communication delay performs more preferably or more robust control.

In general, the control loop implementing new aperiodicity communication technology can be included in enforcement control routine (example Such as PID control routine) controller and the controlled plant of such as valve or valve actuator between wireless, slowly, non- Periodic or asynchronous communication connection or path.Link can use the wirelessly or non-wirelessly communications infrastructure to implement.? In the case of this, control technology uses the aperiodicity communication block being arranged between controller and controlled plant, and wherein, communication block is grasped Make what the quantity and making of the control signal to be sent to controlled plant by minimizing was made in the target location of controlled plant The minimum number of change.

Specifically, so that the power consumed by valve actuator is minimum, the PID output of the calculating of controller only exists Wireless valve just can be sent to when meeting the specific criteria determined by aperiodicity communication block.Due to typically scheduling controller Perform than much more quickly to produce control signal during the minimum that desired value is sent to wireless controlled plant, these standards should With reducing the quantity of the controller signals being sent to controlled plant, thus reduce the controller implemented by controlled plant and move. But the application that standard is in communication block still operates to guarantee to reduce and control signal leading to controlled plant in control signal quantity Letter realizes suitable control performance in the case of postponing.As example, aperiodicity communication block can operate as follows will New target location is sent to controlled plant (via wireless, interval, asynchronous or aperiodicity communication path).First, Aperiodicity communication block will only be in equaling to or more than the quilt of communication since the time that the last communication to wireless controlled plant is later During configuration, and have received that the communication of the confirmation of the last change of the controlled plant target location to being sent to controlled plant Time just send control signal.When these conditions are met, then when exporting at the controller calculated and being sent to controlled plant The absolute value of the difference between ideal value exceedes the dead band (threshold value) being configured and/or when since leading to the last of controlled plant Believe the later time exceed the default report time that is configured any one or the two time, aperiodicity communication block will transmit new Or update control signal.

The calculating of the controller that the target location being sent to wireless controlled plant is typically such as PID controller exports.But Optionally, it is configured when the absolute value of the change determined in controller output after the last target transmitted exceedes During big changing value, the value that the variable quantity of target location can be limited to finally transmit adds or deducts maximum changing value.

When being introduced the minimum delay by the communication between wireless controlled plant and controller, then by wireless controlled plant (such as actuator/valves) is sent to the feedback signal of the valve location form of controller can be in controller positive feedback network Contribute for producing the reset of such as pid control signal.If but with the communication loss of wireless controlled plant or not with the cycle Property mode update, then (such as valve actuator works to reach for the ideal position of the controlled plant transmitted by wireless valve To target location) feedback be determined for controller operation reset contribution.In order to help feeding back to of control system Road determines valve location, in order to being used for calculating reset contribution, control system (or radio network gateway) can provide control signal, and it refers to Determine controlling value (position that such as valve should move to) and valve should make this time moved.This control signal is for control Time sizable situation that signal processed is spent to arrive controlled plant is (such as due to radio network gateway or other are slow or non- Caused by the communication link synchronized) it is useful.The time specified in the control signal can specify absolute time or such as Shift time from the timestamp of control signal.If shift time is configured to more than control signal to arrive from controller The time that controlled plant is spent, then controlled plant just receives control signal and at the appointed time implements change.In this situation Under, controller can assume that control signal is received by controlled plant and at the appointed time implements, therefore can be in this time in control More new valve position in the feedback circuit of device processed, it is not necessary to receive instruction from controlled plant and implement the feedback letter that controller moves Number.This operation can cause more preferable control performance in PID controller.

Accompanying drawing explanation

Fig. 1 is the block diagram of the hard-wired Process Control System typically periodically updated.

Fig. 2 is the mistake exemplified with the process input to the hard-wired Process Control System updated for example periodic The curve chart of journey output response.

Fig. 3 is the block diagram exemplified with example process control system, has controller, and it is with aperiodicity or wireless parties Formula transmits control signals to controlled plant via wireless gateway device, and/or via wireless network receive aperiodicity, non-with Step or the notable feedback signal postponed.

Fig. 4 is the block diagram of example controller, and it uses the aperiodicity being arranged between controller and controlled plant Control signal communication module performs control, and wherein, cordless communication network is passed through in the communication between controller and controlled plant Carrying out, wherein, communication module operation is to reduce the quantity of the controller signals being sent to controlled plant.

Fig. 5 is the block diagram of Process Control System, its implement aperiodicity control communication technology reducing via wireless or Other intervals, slowly or asynchronous communication network is sent to the quantity of controller signals of controlled plant, and also warp By communication path reception feedback signal wireless, slowly or intermittently.

Fig. 6 is the block diagram of Process Control System, and it is wired to reduce in use that it implements aperiodicity control communication technology Or the communication network of synchronous communication is sent to the quantity of the controller signals of controlled plant.

Fig. 7 is exemplified with using write request to control the process communicated to the aperiodicity realizing Fig. 4-6 with write response signal Block diagram.

Fig. 8 is exemplified with for using control communication technology as herein described to realize the control letter from controller to controlled plant Number the sequential chart of signal set of communication, including the control signal of the time specifying application controls to move.

Fig. 9 and 10 is exemplified with relevant to two process control simulations using control communication technology as herein described to implement The curve chart of multiple parameters, and is using the most wired or periodically to control those in the similar control system that communicates identical The curve chart of parameter.

Detailed description of the invention

Control technology enables the controller to aperiodicity, wireless, that slowly, significantly postpone or other are asynchronous Control signal is transferred or transmitted to the controlled plant of process, such as valve actuator by mode, realizes by actuator with minimizing The quantity that actuator moves, still provides the control performance of robust simultaneously.Thus, control technology implementation to reduce the merit of controlled plant The mode of consumption drives the control method of actuator or other controlled plants, reduces the frequent change of controlled plant, and it causes often Occur in " swing " phenomenon controlled in loop disturbed by notable noise or process, and reduce for implementing control loop In wireless network in the communication load in communication equipment, such as wireless gateway device.

Specifically, controlling the control communication block operation in loop, based on multiple configuration factors, such as communicate dead band, control Signal intensity threshold value processed with communicate during, send the newly generated control signal generated by controller in aperiodicity mode.This Outward, in order to regulate the control of equipment in the presence of delayed control signal, the wave filter updated continuously in controller based on The reality of controlled plant or implicit location, generate the finger of expection process response during each control routine iteration of controller Show (also referred to as feedback contribution).This feedback contribution is in the controller for generating controller and reception the base of control signal Suitable control is guaranteed there is notable delay between the controlled plant of action in control signal in the case of.In certain situation Under, the wave filter updated continuously can in part with from the term of execution of last control routine iteration and control routine with The instruction of the intended response of front generation, to generate the instruction of intended response during each control routine iteration.

It addition, when process measurement feedback signal is supplied to controller in the way of interval, aperiodicity or delay, Only when receiving new measurement instruction, current output of the wave filter updated continuously can serve as feedback contribution, such as controller Interior integration (also referred to as resetting) and/or differential (also referred to as ratio) contribution.In general, in the case, integration output is opened Close maintain last measured value update as to the integration of control signal or reset contribution and when being received by controller, by continuous the most more The expection process response that new wave filter generates.When new measured value updates available, integration output switch is clamped to by the most more The new instruction of the expection process response that new wave filter generates is upper (instruction updated based on new measured value), and as control signal Integration or ratio contribution the response of new expection process is provided.As a result, controller uses the wave filter updated continuously at each Determining the intended response of new process during controlling iteration, wherein, each new expection process response is reflected in measurement updaue Between the impact of change made of time, and thus affect the controller output in the evolution of control signal, even if only When new value of feedback can use at controller, just change integration or the reset component of the control signal produced by controller.

May be used for implementing the Process Control System 10 shown in Fig. 1 of control method described herein and include process controller 11, it is connected to data history records 12 and one or more host workstations or computer 13 (its via communication line or bus 9 Can be any kind of personal computer, work station etc.), each there is display screen 14.Communication network 9 can be such as Ethernet, WiFi network or any other wired or wireless network.Controller 11 also blocks 26 and 28 via input/output (I/O) It is connected to field apparatus 15-22, and is shown as using one or more hard-wired communication network and communication plan communicably It is connected to field apparatus 15-22.Data history records 12 can be any data collection module wishing type, has for depositing Any memorizer wishing type of storage data and any wish the known software of type, hardware or firmware.

Generally, field apparatus 15-22 can be any kind of equipment, such as sensor, valve, transmitter, localizer etc., And I/O card 26 and 28 can be any kind of I/O equipment, meet any desired communication or controller protocol.Controller 11 include processor 23, and it is implemented or monitors storage one or more process control routine in memory 24 (or any mould Block, block or its subroutine).In general, controller 11 leads to equipment 15-22, host computer 13 and data history records 12 Letter, controls process in any desired manner.Additionally, controller 11 use be commonly called functional device implement control plan Omiting or scheme, wherein, each functional module is an object or other part (e.g., subroutine) of master control routine, its Loop is controlled with implementation process in Process Control System 10 in conjunction with other functional devices (via the communication of referred to as link) operation.Merit Can typically perform one below by block: input function, such as relevant to transmitter, sensor or other process parameter measurement device 's；Control function, such as relevant to the control routine performing the control such as PID, fuzzy logic；Or output function, it controls one The operation of a little equipment, such as actuator or valve, to perform some physical functions in Process Control System 10.Certainly, mixing Exist with other kinds of functional device and can use at this.As described below, functional device can be stored in controller 11 or other Perform in equipment and by controller 11 or other equipment.

As shown in the block of decomposition 30 of Fig. 1, controller 11 can include multiple single calabash control routine, it is shown that for controlling example Journey 32 and 34 if desired, it is possible to implement one or more senior control loops, it is shown that for control loop 36.Each This control loop is commonly referred to control module.Unity loop control routine 32 and 34 is shown as performing unity loop control, uses list Input/mono-output fuzzy logic control block and single input/mono-output PID control block, be connected respectively to suitable analog input (AI) and analog output (AO) functional device, they can become with the process control equipment of such as valve, such as temperature and pressure Any other equipment in the measurement equipment of device or sensor or Process Control System 10 is sent to be associated.Senior control loop 36 It is shown as including senior control block 38, has and be communicatively connected to the input of one or more AI functional device and communicably connect Receive the output of one or more AO functional device, although the input of senior control block 38 and output may be coupled to any other institute Desired functional device or control element are to receive other kinds of input, and provide other kinds of control to export.Senior control Block 38 can implement any kind of multiple-input and multiple-output control program, may be constructed or include Model Predictive Control (MPC) block, Neural net model establishing or control block, Multivariable Fuzzy logic control block, real-time optimizers block etc..It will be appreciated that include senior control Functional device shown in Fig. 1 of block 38 can be performed by independent control 11, or alternatively, it is possible to is positioned at process control system Any other processing equipment of system or control in element and be executed by, such as one of work station 13 or field apparatus 19-22 it One.Exemplarily, field apparatus 21 and 22 can be transmitter and valve respectively, can perform to control element, is used for implementing control Routine processed, thus can include processing and other assemblies, for executable portion control routine, the most one or more functional devices. Specifically, field apparatus 21 can have memorizer 39A, for storing the logic relevant to simulating input block and data, and Field apparatus 22 can include actuator, has memorizer 39B, for storage with and the PID that communicates of analog output (AO) block Or other control the relevant logic of block and data, as shown in Figure 1.

The curve chart of Fig. 2 is generally exemplified with (and/or being positioned at existing based on controlling the one or more of loop 32,34 and 36 Field device 21 and 22 or other equipment in any control loop comprising functional device) enforcement, in response to Process Control System Process input produce the output of process.The control routine implemented generally is held in multiple controller iteration in a periodic fashion OK, there is the time performed along the control routine shown in time shaft by block arrow 40 in Fig. 2.In normal conditions, each control Routine iteration 40 processed is surveyed by the process with the renewal shown in block arrow 42 provided by such as transmitter or other field apparatus Amount is supported.As in figure 2 it is shown, typically there is multiple periodic process to measure 42, performed by each periodically control routine Control routine between time 40 is made and is received.In order to avoid performing, with control, the restriction that locking phase associates with by measured value, Many known Process Control Systems (or controlling loop) are designed to measure with the factor over-sampling process variable of 2-10 times.This Kind of over-sampling contribute to guaranteeing process variable measure currently each control routine perform or during iteration in the control scheme Use.Additionally, so that control change minimum, conventional design layout appointment control based on feedback should be than process response time Fast 4-10 times of ground performs.Still further, in conventional design layout, in order to ensure Optimal Control performance, at each controller The control signal produced at the outfan of controller in the term of execution is sent to controlled plant, and controlled plant is grasped based on controlled plant Make and action or realize controlled plant operation.Process response time shows in the output of process response curve 43 of the curve chart of Fig. 2 (show in the lower section line 45 of Fig. 2) and process time constant (τ) after going out the enforcement for the Spline smoothing 44 in inputting in process The relevant time (such as, the 63% of process variable variations) is plus process lag or (T idle hours_D).Under any circumstance, for Meeting these conventional design layout requirements, process measurements updates (shown in the arrow 42 of Fig. 2) to hold than control routine Scanning frequency rate (shown in the arrow 40 of Fig. 2) faster polydispersity index is also supplied to controller, and control routine performs speed again More faster than process response time or much higher.

But in some control systems configure, such as, wirelessly send control signal or from one or many at controller Individual field apparatus receive process variable measure control system configuration in, it is impossible to guarantee controller each output with The method of synchronization or control signal send and this signal between the reception of controlled plant, only there is minimum time lingeringly The mode arriving controlled plant sends control signals to controlled plant.Additionally, the process from the system of these types obtains Obtain frequently and periodically measurement sample is probably unpractical, even not possible with.Specifically, in these situations Under, controller is only capable of reception non-periodic process variable and measures, and/or surveys in aperiodicity or even periodic process variable Time between amount can perform speed (shown in the arrow 40 of Fig. 2) more than control routine.

Fig. 3 shows exemplary part wireless process control system 10, and it can show above-mentioned problem, thus can not Use and perform acceptable or desired control relative to the typical technology that controls described in Fig. 2.But herein in relation to Fig. 4- New control technology described in 10 can be implemented in the factory-configured of Fig. 3, so that controlling of controlled plant is mobile minimum Mode performs control, simultaneously at the process control signal existed between controller and controlled plant and/or sensor or transmitter And perform control in the case of the aperiodicity that the process variable between controller is measured, communication that is wireless and/or that significantly postpone System.Specifically, the control system 10 of Fig. 3 similar in nature to the control system 10 of Fig. 1, similar element has identical Numbering.But the control system 10 of Fig. 3 includes multiple field apparatus 60-70, and it is such asCommunication network Wireless in the wireless network 72 of network it is communicably coupled to each other, and is coupled to controller 11 via gateway device 73.Such as Fig. 3 institute Showing, in network 72, the field apparatus of wireless connections is connected to or includes antenna 75, and antenna 75 coordination with one another also cooperates with antenna 76 (it is coupled to gateway device 73) is to carry out radio communication in network 72.In one case, it is shown that for the one of equipment 61-64 A little field apparatus are connected to radio network gateway or conversion equipment 76 via hardwired line, and it performs for this in wireless network 72 The communication of a little equipment.Certainly, other equipment in wireless network 72 can be wireless device, can each have their own Wireless communication module, in wireless network 72 perform radio communication.Additionally, field apparatus 60-70 can be any class The field apparatus of type, such as, include transmitter/actuator (such as valve actuator), valve etc..

It will be appreciated that each in transmitter 60-64 and 66-69 of Fig. 3 can would indicate that respective process variable (example Such as flow, pressure, temperature or liquid level signal) signal via cordless communication network 72, gateway device 73 and network 9 be sent to control Device 11 processed, in order to use in the one or more control loops implemented in controller 11 or routine.Be referred to as controlled plant its His wireless device, the such as valve shown in Fig. 3 or valve actuator 65 and 70, can from controller 11 wirelessly or part Process control signal is wirelessly received (such as via network 9, gateway 73 and wireless network 72).Additionally, these equipment can be by It is configured to, by wireless network 72, (other signals are such as represented the current location of such as equipment or any other process of state The signal of parameter, confirmation signal etc.) it is sent to other equipment in controller 11 and/or factory 10.In general, such as Fig. 3 institute Showing, controller 11 includes communication stack 80, its perform on processor 23 with process input signal, module or routine 82, its Processor 23 performs when include with the signal of detection input measurement updaue or detection from control in loop or with control Other signals of the equipment that loop is relevant, by one or more control modules 84, it performs with based on measurement on processor 23 Update and perform control.Detection routine 82 can generate mark or other signals, to represent the packet provided via communication stack 80 Include new process variable to measure or other kinds of renewal.New data and renewal mark can be supplied to one or more subsequently Control module 84 (it can be functional device), control module 84 is performed speed by controller 11 with predetermined periodicity subsequently and performs, As described in detail further below.Alternatively, or additionally, new data and renewal mark can be supplied at controller 11 Or the one or more monitoring modules performed in other positions in control system 10 or application program.

Thus, as it has been described above, the Process Control System 10 of Fig. 3 generally uses control signal and by transmitter 60-64 and 66- 69 or such as field apparatus 65 and 70 other control elements measure, sensing or calculate being wirelessly transferred of data perform Control.Exemplarily, in the Process Control System 10 of Fig. 3, set to such as the controlled of one of valve 65 or 70 from controller 11 Standby new control signal is sent to this equipment via gateway device 73 and wireless network 72.Additionally, in some cases, it is used for The new process variable that the feedback of controller 11 calculates measures or other signal values can be via wireless network 72 by equipment 60-64 With 66-69 aperiodicity, interval or slowly on the basis of be sent to controller 11, the most only when meeting specified conditions. Such as, scheduled volume is changed when process variable value relative to the last process variable measurement being sent to controller 11 by equipment Time, new process variable measurement can be sent to controller 11.It is of course also possible to implement or replace to determine when with aperiodic Property mode sends other modes of process variable measurement.

Under any circumstance, controller 11 (it performs to control to calculate) with receive the controlled plant of control signal (such as Valve or actuator device) between, and (it is controlling calculating with controller 11 at sensor (it measures controlled process variable) Feedback circuit in use sensor signal) between communication path in exist cordless communication network 72 and/or use gateway set Standby 73 so that the communication controlled in loop is asynchronous in communication process, aperiodic and/or significantly postponed.Such as, EnterTypical radio network gateway in network can will control the communication delay 3-6 second, is using these High-speed synchronous is made to control difficulty during network.This delay can also be by signal sensor in cordless communication network or change Occur when sending the controller that device equipment is sent to outside this network.

Thus, exist between the equipment in the wireless network of controller 11 and Fig. 3 radio communication typically result in asynchronous, Notable that postpone and/or acyclic communication, it produces again between controller 11 and field apparatus 60-64 and 66-69 not Rule or the most frequently data transmission and/or vice versa.But as mentioned above, control signal is to wired field device Transmission and the measured value of 15-22 are configured to perform in a periodic fashion from the transmission of wired field device 15-22 traditionally, thus The periodicity propping up again control routine in held controller 11 performs.As a result, in controller 11, typical control routine is commonly designed use Periodically updating of the process variable measurement used in the feedback circuit at controller 11.

In order to adapt to such as be introduced by the wireless communication hardware being arranged between controller 11 and at least some field apparatus The aperiodicity controlled in loop or the notable control postponed and measure signal, control and the monitoring routine of controller 11 are permissible Reconstruct as described below or revise so that Process Control System 10 can be that use aperiodicity or other intervals or notable During the signal of communication postponed, especially in the execution speed (such as periodically performing speed) of these signal transmission & control devices 11 Compare and suitably run when infrequently occurring.

Illustrate in more detail the exemplary control being configured with the relevant traffic operation of aperiodicity control in the diagram Scheme processed or control system 400, Fig. 4 schematically illustrates and couples the process controller 100 with control process 101.Concrete and Speech, controller 100 is coupled to the wireless actuator 102 of process 101 via wireless communication link 103 (in Fig. 4 shown in broken lines). In the case, actuator 102 is controlled plant, such as, could be for the actuator of valve, in Valve controlling process 101 Fluid flow.By controller 100, (it can be a wireless field device of the controller 11 of Fig. 1 and 3 or such as Fig. 3 The control element etc. of field apparatus) control program implemented generally includes and combines shown in Fig. 3 and described communication stack 80, update inspection Survey module 82 and the function of one or more control module 84.

In the example system of Fig. 4, controller 100 is such as from one of work station 13 (Fig. 1 and 3) or from process control Any other source that is in system 10 or that communicate with Process Control System 10 receives set point signal, and operate to generate one or Multiple control signals 105 (or controller moves), it is supplied to via wireless communication link 103 from the outfan of controller 100 Wireless actuator 102.Except receiving in addition to control signal 105, process 101 (or can actuator 102) in process 101 can That can be measured or immeasurablel interference.Depending on the type that process control is applied, set point signal can be in process 101 Control during any time change, such as by user, regulation routine etc..Certainly, process control signal can control with The actuator that the removable control element of valve or any other type is relevant, or can control any other field apparatus with Change is caused in the operation of process 101.Process 101 to the response of the change in process control signal 105 by being such as Corresponding to any one transmitter, sensor or other field apparatus 106 in transmitter 60-64 or 66-69 shown in Fig. 3 Measure or sensing.Communication link between transmitter 106 and controller 100 is shown in Figure 4 for hard-wired communication link, Its by synchronizing, periodically or instant feedback signal is supplied to controller 100 but it also may be with the least or carry without delay Communication link for any other type of feedback signal.

In the simplest embodiment, controller 100 can implement single/input, list/output closed-loop control routine, such as PID Control routine, it is the PID type control routine of a kind of form.PID type control routine used herein includes arbitrary ratio (P), integration (I), differential (D), proportional, integral (PI), proportional-plus-derivative (PD), Integrated Derivative (ID) or proportional-integral-differential (PID) control routine.Therefore, controller 100 includes several standard PID controller element, including control signal signal generating unit, tool Sum block 108, sum block 108 is had to produce the error signal between the process ratio of set point and measurement, proportional gain element 110, another sum block 112 and height limiter 114.What control routine 100 also included comprising wave filter 116 directly feeds back road Footpath.In the case, wave filter 116 is alternatively coupled to the outfan of height limiter 114, or as shown in Figure 4, can with coupling Close actuator 102, to receive implicit actuator position signal, for calculating the control letter produced by process controller 100 Number reset (or other) control component.In general, the outfan of wave filter 116 is connected to summer 112, summer 112 Reset (integration) component produced by wave filter 116 is added to the proportional component produced by gain unit 110.It addition, such as Fig. 4 institute Showing, controller 100 can include differential component computing block 132, itself and the element being specifically designed to calculating ratio and integral contribution Error signal is received concurrently from sum block 108.Here, the differential component of control signal is added to summer 112 by summer 134 Output, to produce pid control signal, there is ratio, differential and quadrature components.Certainly if desired, summer 112 Individual unit can be merged into 134.Merge additionally, ratio, integration and derivative contribution to be shown in sum block 112 and 134 To produce the most limited control signal, although other PID structures (such as serial structure) can be used.

Specifically, in the operating process of controller 100, set point signal is carried by sum block 108 with from transmitter 106 The process variable measurement received recently of confession compares to produce error signal.Proportional gain element 110 will be such as by missing Difference signal is multiplied by proportional gain value K_pAnd computing is to produce proportional contribution or the component of control signal in error signal.Sum block 112 subsequently by the output (i.e. proportional contribution) of booster element 110 and by feedback path, specifically, by wave filter 116, produces Control signal integration or reset contribution or component merge.Summer 134 increases the differential component produced by block 132 to produce The most limited control signal.Limiter block 114 performs high lower limit subsequently to produce control signal in the output of summer 134 105, it is used for the process that controls 101, specifically, controls actuator 102.

Additionally, as shown in Figure 4, coupling filter 116 with via wireless communication link (its can be with for by control Signal is sent to the link that the link 103 of actuator 102 is identical) receive implicit position from actuator 102.Wave filter 106 with Mode as detailed below uses this implicit positional value to determine reset (integration) component of control signal 105.In general, When due between controller 110 and wireless valve or actuator 102 communication introduce the minimum delay time, by wireless actuator/ Valve 102 sends back the valve position feedback (i.e. implicit positional value) of controller 110 and may be used for (i.e. filtering in positive feedback network In ripple device 116), to produce the reset contribution of PID controller 100.If here, with the communication loss of wireless valve 102 or do not have Have and update in a periodic fashion, then the feedback of the last target valve position transmitted by wireless valve or actuator 102 is (i.e. The actuator 102 finally known works the target location reached) can serve as the position implied, input into renewal continuously In wave filter 116.

It is essential that as shown in Figure 4, controller 100 control routine implemented also includes controlling communication block 135, its May be used to proper use wireless valve or cause in control signal to the transmission of controlled plant notable delay some its When his communication network is implemented to control, that used by actuator 102 or be supplied to the target location of actuator 102 is made The minimum number of change.Specifically, so that be sent to the minimum number of actuator 102 control signal, so that valve Door actuator 102 power consumption is minimum, and block 135 is only when meeting specified criteria, just by the controller output calculated or control letter Number 105 (being produced by control routine in a periodic fashion) are sent to wireless actuator 102.In general sense, these criterions The quantity of the use control signal change that makes to be sent to actuator 102 reduce or minimum, remain to execution process robust simultaneously Control.

In general, typically scheduling PID controller 100 uses block 135 desired value of actuator 102 to be sent to ratio The speed that the maximum rate of wireless actuator 102 is faster performs.Specifically, block 135 is only since being sent to wireless actuation Device 102 finally communicates during the communication equal to or more than configuration of the later time, and the last change that actuator is to target location The new value of control signal 105, when block 135 receives, is just sent to actuator 102 by the communication of confirmation changed.If If wishing, can be less than or equal to the enforcement communication block 135 with the communication of controlled plant during the communication of configuration performs speed Rate so that the operation of communication block 135 or execution be configuration communication during pass by (i.e. since sending out in front control signal After delivering to controlled plant, elapsed time is more than minimum time threshold value) implicit determine.Under any circumstance, if meeting these Condition, then block 135 just meet two other signals transmission criterions any one or the two time, by new target location (control signal 105 that is the newest or that update) is sent to actuator 102.Specifically, if the new control signal calculated with The absolute value being sent to the difference between the final control signal of actuator 102 exceedes the dead band value of configuration (i.e. threshold value) and/or such as Fruit is since the default report time exceeding configuration to the last later time that communicates of actuator 102, then control communication block 135 Just the control signal 105 newly calculated is sent to actuator 102.If being unsatisfactory for these conditions, then just control communication block 135 The control signal 105 newly calculated is not sent to actuator 102.

Thus, in general, by control the routine implemented of communication block 135 during the communication of each configuration (its typically The term of execution of being set greater than or be equal to controller) at most only send a secondary control signal, and only receive transmission at controller During the confirmation the most received by actuator to the final control signal of actuator.This initial condition set guarantees to control Device sends control signal and is not more than special speed, and when when front control signal may also not received by actuator (by the past The actuator of the control signal sent determines) do not send new control signal.If additionally, meeting these conditions (i.e. Since last control signal being sent to the time that is that the actuator 102 later time is more than configuration or that preset, and actuator 102 it has been acknowledged that receive last control signal), then the only value in new control signal is believed with the control sent in the past Number value difference predetermined threshold be and/or exceeding the default of configuration since the time after the last communication of actuator 102 During report time, just send new control signal.

Communication block 135 accordingly ensure that only receive in front control signal at actuator 102 it turned out, and from Pass by after sending last control signal (being determined by during the communication configured) specific minimum time amount time, and only When the value disparity threshold amount of value and the control signal received recently of new control signal to be sent, or since sending out (even if the difference in the value of control signal is not when after sending last control signal, time to current time exceedes specific threshold Equal or exceed threshold value), just new control signal is sent to actuator 102.Decrease in this actionable total and be sent to cause The quantity of the control signal of dynamic device 102, thus the quantity that the actuator needed for decreasing controller moves, but with real during the course The mode of the control having showed robust is carried out.

Additionally, if desired, block 135 the valve mesh of wireless actuator 102 it is sent to as part control signal Cursor position can be generally calculating output (value of the most nearest control signal 105) of control routine.But optionally, target position Put value (the i.e. amount of the change in control signal between the continuous control signal being sent to actuator 102 communicates of change Value) can be limited to the control that finally transmits or desired value plus or deduct maximum changing value.Thus, when in new control signal And when between the last control signal transmitted, in control signal, the absolute value of change exceedes the maximum changing value of configuration, new transmission Control signal (or desired value) can be restricted to the signal value with this maximum change.In this way, controlling communication block 135 can Be limited in the continuous control signal of actuator 102 communicate between the amount of change in control signal.In the last control transmitted Wish that this is limited when the feedback of signal processed or confirmation are by notable delay to operate, to prevent jump big in control signal, It can cause poor control performance.

The advantage of this communication means is, when the last control transmitted being supplied to controller 100 by wireless actuator 102 Value or the feedback of target location or confirm when the transmission of (i.e. implicit actuator position) has the minimum delay, this value can be Positive feedback network is used for (such as by wave filter 116) calculate PID reset component.This operation compensates automatically by wireless actuation Any delay of the communication introducing of device 102 or change, the change in therefore regulating without PID compensates and is sent to target location Delay in valve.As a result, PID controller regulation strictly according to process gain and is dynamically set up, and is introduced by communication Postpone unrelated.

Specifically, above-mentioned control Communications routines is used still to make wave filter 116 be operable to provide the Shandong of process Rod controls, and reduce simultaneously the mode of the communication between controller 100 and actuator 102 to produce control signal integration or Reset contribution component.Specifically, coupling is to receive implicit actuator position (from actuator 102 via such as radio communication Path sends) wave filter 116 based on implicit actuator position and control algolithm 100 the term of execution or the time, produce The instruction that the expection process of control signal 105 is responded.In the case, implicit actuator position can be at actuator The 102 nearest control signals (or target location of nearest control signal) received, wherein, control signal instruction actuator 102 positions to be moved to.Upon execution, as shown in Figure 4, expection process response signal is supplied to summation by wave filter 116 Device 112.If desired, wave filter 116 the expection process response of the change in the output to summer 108 produced can To use first order modeling to approximate, as detailed below.But more generally, it is contemplated that process response can use any of process 100 Suitable model produces, and is not limited to the process model relevant to the integration determining control signal or the contribution that resets.Such as, utilized The controller that journey model provides expection process to respond can comprise or not comprise derivative contribution so that control routine 100 is permissible Implement PID or PI control program.

Before the operation of wave filter of Fig. 4 is discussed in more detail, it is noted that positive feedback network can be used to determine integration Or reset that to implement conventional PI control device be useful in contribution.Mathematically show, the transmission function etc. of traditional PI embodiment Valency in for without constraint control, i.e. export unrestricted, normalized form.Specifically:

Wherein, K_p=proportional gain

T_Reset=reset, the second

O (s)=control output

E (s)=control error

As shown in Figure 4, the positive feedback path from actuator 102 is used to provide of implicit actuator position excellent Point is when controller output is by high or low restriction, i.e. by limiter 114, is automatically prevented from reset contribution and terminates.

Under any circumstance, control technology as herein described all achieve controller receive process variable periodicity or Use positive feedback path to determine reset contribution when aperiodicity updates, occur in the reception that new process variable is measured simultaneously Between set point change or feedforward change in the case of, still achieve robust controller response, also limit in mistake simultaneously The quantity that in the operating process in process control loop, actuator moves.Specifically, in order to provide the set point change of robust to operate, Wave filter 116 be configured to controller 100 each or calculate the new instruction of expection process response during perform every time Or value.As a result, the output of wave filter 116 performs again to regenerate in periodic process in each of controller routine, even if to filtering The input (implicit location of actuator 102) of ripple device 116 can not update in this periodic basis.

Generally, each control to perform in periodic process according to implicit actuator position, last (i.e. front tightly It is close to) instruction of the expection process that produced by wave filter 116 during controller execution cycle response and the term of execution controller Calculate the new instruction of the expection process response produced by wave filter 116.As a result, wave filter 116 is by the most more in explanation herein Newly, because performing it during each controller execution cycle and estimating to produce new process response.Set forth below each Can implement to produce new expection process response or wave filter by the wave filter 116 updated continuously during the individual control execution cycle Exemplary equation:

Wherein, F_N=new wave filter exports

F_N-1The output of=wave filter is last to be performed

O_N-1=implicit actuator position (final control signal such as received by actuator)

The term of execution of Δ T=controller

Here, it may be noted that by new wave filter output F_NIt is defined as iteratively nearest exporting F at pre-filter_N-1 (i.e. present filter output valve) adds attenuation components, and the nearest controller that described attenuation components is defined as receiving at actuator is defeated Go out value (or target location) O_N-1(implicit actuator value) and present filter output valve F_N-1Between difference be multiplied by depend on multiple Bit time T_ResetWith the factor of Δ T term of execution of control.

Use the wave filter updated continuously in this way, as long as control routine 100 is receiving new process variable measurement When just calculating integral control signal component, it is possible to preferably determine that expection process responds, hence for set point or occur in two The change in other feedforward interference between the reception of individual process proportion measurement is easier to make a response.Specifically, it may be noted that Arriving, the change (being not received by new process measurements) in set point can immediately result in the mistake of the outfan at summer 108 Change in difference signal, this changes the proportional contribution component of control signal, thus changes control signal.As a result, wave filter The 116 new intended responses that can immediately begin to the generation process control signal to changing, thus can receive at controller 100 and ring Its output is updated in this change before the new process measurements should measured.Subsequently, survey when controller 100 receives new process Value, and wave filter output sample be clamped to summer 112 input for use as control signal integration or reset contribution point During amount, wave filter 116 iterate to expection process response, its most to process 101 in set point The response changed is made a response or has contained the process 101 response to the change in set point.

Thus, it will be understood that by the wave filter 116 updated continuously, (such as reset the control technology shown in Fig. 4 contribution filter Ripple device) calculate the instruction to each the expection process response performed controlling block or routine 100.In the fig. 4 embodiment, control Device 100 processed configures the wave filter 116 of renewal continuously to calculate the instruction to each intended response performed controlling block.Cause And, the wave filter 116 updated continuously is based on implicit actuator position (control signal such as received recently at actuator 102) The Continuous plus instruction to the intended response of the iteration each time of control routine, it is contemplated that this new instruction of response is held at each Sum block 112 it is delivered to during line period.

This controls technology and allows the continuous wave filter 116 updated to model, expection process response in spite of biography continuously Send new measured value, and without determining whether current controller output will be sent to actuator 102.If as based on measurement The set point change of interference or the result of feedforward operation, control output and change, the wave filter 116 updated continuously is by based on cause The new instruction that the implicit location of dynamic device 102 calculates at the intended response of control routine iteration each time correctly reflects expection process Response.

It should be noted that the output of wave filter 116 is directly used as control signal by the simple PID controller structure of Fig. 4 Reset contribution, in the case, and reset contribution (continuous renewal filter equations the most set forth above) of closed loop control routine The accurate expression that process responds can be provided when whether process shows stable state behavior determining.But other processes, such as rest The process that time is leading, it may be desirable to be incorporated to extra component in the controller of Fig. 4, in order to expection process response modeling.Close In the process that can be represented well by first order modeling, process time constant is commonly used for as PI (or PID) controller true Determine resetting time.Specifically, if being set equal to process time constant resetting time, reset contribution would generally offset ratio Contribution, so that as time go by, control routine 100 reflects that expection process responds.In the example depicted in fig. 4, reset tribute Offer and can be realized by the time constant identical with process time constant by the positive feedback network with wave filter 116.Although Other models can be utilized, but positive feedback network, wave filter or model provide for determining have the known or process of approximation The convenient mechanism of the intended response of the process of time constant.

Fig. 5 and 6 is exemplified with some other examples of control system, and it can use above in regard to the communication described in Fig. 4 Control or filtering technique provide the control of robust in response to set point change, the most also make the controller in controlled plant Mobile minimum.Specifically, in some applications, wired or wireless transmitter or sensor and such as valve is wired or wireless Multiple various combinations of controlled plant may be used in control program.Specifically, it is desirable to implement above-mentioned control technology so that Must include in the control loop of wireless transmitter and wired valve or actuator, include wire transmitter and wireless valve or actuating In the controlling in loop, include the control loop of wireless transmitter and wireless valve or actuator of device (such as shown in Fig. 4), And/or the controller controlled in loop including wire transmitter and wired valve or actuator moves minimum.Here, can manage Solving, the wireless communications path in example described herein supposes between controller and actuator and/or at transmitter (sensor) And introduce slow, interval, asynchronous, the acyclic and/or transmission of limited delay between controller, as herein described Same concept or control technology for these networks can apply to have and include any logical of these characteristics one or more The control system of communication network, even if these communication networks or control system are not the most wireless.

Fig. 5 exemplified with Exemplary control system 500 or control loop, it include wireless transmitter (and therefore wireless instead Feedback communication path) and wireless valve or actuator (and wireless control signal communication path therefore).Assuming that significantly postpone, lose Inactivating signal, aperiodicity or asynchronous communication are likely to be due to any one of the two wireless communications path and introduce.Shown in Fig. 5 Control system 500 be essentially similar to Fig. 4, except the controller 100 of Fig. 5 includes extra assembly, need it to solve The delay of the potential communication in feedback communication path between sensor 106 and controller 100 or loss, and/or asynchronous Or the loss of periodical communication.As seeing, this path is represented by dotted lines the most in Figure 5, to indicate this to communicate Path is wireless, acyclic, asynchronous and/or shows notable delay.

As shown in Figure 5, controller 100 includes above in regard to the standard PID controller element shown in Fig. 4, including control Signal signal generating unit processed, control signal signal generating unit have sum block 108, proportional gain element 110, another sum block 112, Differential calculation block 132, yet another sum block 134 and height limiter 114.Control routine 100 also includes comprising wave filter 116 Feedback path, but in the case, additionally include integration output switch, it includes selecting block 118, is coupled to communication stack 80 With wave filter 116.As it is shown in figure 5, wave filter 166 still couples to receive implicit actuator position, but now by wave filter 116 Output be supplied to block 118, controller 100 integration generated or reset component are supplied to sum block 112 again by block 118.

In the operating process of controller 100, set point signal is measured by sum block 108 with the process variable received recently Value (communication stack 80 from controller 100 provides) compares to produce error signal.Proportional gain element 110 such as passes through Error signal is multiplied by proportional gain value K_pAnd computing in error signal

To produce proportional contribution or the component of control signal.Sum block 112 subsequently by the output of booster element 110 (i.e. than Example is contributed) with the integration of the control signal produced by feedback path (including wave filter 116 and block 118) or reset contribution or component Merge.Differential component block 132 goes up the computing differential component with generation control signal in the output (error signal) of summer 108, It is added to the output of summer 112 by summer 134.Limiter block 114 performs high lower bound subsequently in the output of summer 134 System, to produce control signal 105, provides it to control communication block 135.Block 135 is grasped in the way of as above relative to described in Fig. 4 Make to determine when new control signal 105 is sent to actuator via wireless link 103 (it may significantly be postponed) 102。

In the case, the wave filter 116 in the feedback path of controller 110 and block or switch 118 operation are with such as lower section Formula produces the integration of control signal or the contribution component that resets.Coupling is to receive the wave filter 116 of the output of limiter 114 based on hidden The actuator position that contains and control algolithm 100 the term of execution or the time produce what the expection process to control signal 105 responded Instruction.But in the case, this expection process response signal is supplied to switch or block 118 by wave filter 166.As long as controlling Device 100 receives new process variable measurement (being determined by communication stack 80), and switch or block 118 are just switching or block 118 Output sampling the output of clamping filter 116, and keep this value, until receiving next process variable at communication stack 80 Measured value.Thus, the output of switch 118 keeps the output of wave filter 116, and it is to receive last process at controller 100 to become Produce when measurement updates.

Specifically, by the wave filter 116 updated continuously, (such as reset the control technology shown in Fig. 5 contribution filtering Device) calculate the instruction to each intended response performed controlling block or routine 100.But in order to determine the defeated of wave filter 116 Go out whether to apply the input accomplishing sum block 112, communication stack 80 and in some instances, update detection module 82 (Fig. 3), process From the input data of transmitter 106, with when receiving new process variable measurement, generate newly for integration IOB 118 Value mark.This new value flag notification switch 118 is that the output of wave filter 116 is sampled and clamps by this controller iteration, and This value is supplied to the input of summer 112.

Mark newly it is worth, each to control routine of the wave filter 116 all Continuous plus updated continuously in spite of transferring The instruction of the intended response of secondary iteration.This new instruction of intended response is delivered to integration output in each execution controlling block Switch or block 118.Depending on whether to exist and be newly worth mark, integration output switch 118 is allowing from the wave filter updated continuously The new instruction of the intended response of 116 is by be sent to sum block 112 and to keep in the past during the last execution controlling block It is delivered between the signal of sum block 112 switching.Specifically, when transmitting new value mark, integration output switch 118 allows From the instruction of the anticipated impact calculated recently of the wave filter 116 updated continuously by be sent to sum block 112.On the contrary, as Fruit does not exist and is newly worth mark, then integration output switch 118 is just by the instruction from the last intended response controlling block iteration Resend to sum block 112.In this way, transmitting from stack 80 each time and be newly worth mark, integration output switch 118 is just clamped to In the new instruction of intended response, but if there is no being newly worth mark, do not allow for the new expection calculated produced by wave filter 116 The instruction of response arrives sum block 112.

Thus, it will be understood that use block 118 that the response of expection process can be built by wave filter 116 continuously that update continuously Mould, in spite of transferring new measured value.If controlling output as set point change based on the interference measured or feedforward The result of operation and change, be newly worth mark in spite of existing, the wave filter 116 updated continuously all pass through to calculate in each control The new instruction of the intended response of routine iteration processed and correctly reflect that expection process responds.It is anticipated that the new instruction of response (i.e. resets Contribution or quadrature components) only when transferring new value mark, (via integration output switch 118) is just included in controller calculating In.

Thus, in general, the control routine of Fig. 5 by calculated based on the aperiodicity received at communication stack 80, That postpone or asynchronous measured value, additionally also determines that the intended response between the reception of two measured values simultaneously, with consider by The change changing or causing with the interference of any measurement of the feedforward input accomplishing controller 100 in set point, produces pre- Phase process responds.Thus, above-mentioned control technology can adapt to affect set point change, the measurement that expection process responds Feedforward operation etc. in interference, thus exist and control signal to the transmission of actuator 102 and feedback or measurement process variable Signal at controller 100 when receiving relevant communication delay, it is provided that more robust control responds.

Additionally, as it is shown in figure 5, the feedback signal received recently is supplied to summer 108 by communication stack 80, in order to based on by Calculation is in the error signal of the output of summer 108.Also shown in FIG. 5, communication stack 80 the new value mark produced is also provided to Differential calculation unit 132, it is possible to be used for indicating differential calculation unit when should recalculate or operating to produce differential control Component.For example, it is possible to reconstruct derivative contribution block 132 based on elapsed time after last measurement updaue.In this way, Avoid the spiking in derivative contribution (and the output signal obtained).

Specifically, in order to adapt to transmission that is insecure in feedback communication path or that postpone, and more generally, measure more New not may utilize, and derivative contribution may remain in the value finally determined, until as being worth mark institute by from the new of communication stack 80 That shows receives measurement updaue.This technology allows control routine to continue according to the execution speed of the normal of control routine or foundation Carry out periodically performing.After the measurement receiving renewal, as shown in Figure 5, micro-tiling 132 can determine according to below equation Derivative contribution

O_{D} = K_{D} \cdot \frac{e_{N} - e_{N - 1}}{Δ T}

Wherein, e_N=error current

e_N-1=last error

Δ T=is elapsed time after transmitting new value

O_D=controller differential term

K_D=differential gain factor

By this technology for determining derivative contribution, permissible for the measurement updaue of process variable (i.e. controlling input) One or more the term of execution, value is lost, without producing output spike signal.When rebuilding communication, in derivative contribution equation Item (e_N-e_N-1) the identical value generated with the standard calculations in derivative contribution can be generated.But for standard PID skill Art, the divisor in determining derivative contribution is carried out period.On the contrary, control technology as herein described utilizes two continuous receptions Measurement between elapsed time.The term of execution of being more than by elapsed time, control technology and produce less than standard PID technology Derivative contribution and the spiking of reduction.

In order to aid in determining whether elapsed time, communication stack 80 can be by above-mentioned new value mark together with two proximity Between the value received, elapsed time is supplied to micro-tiling 132, as shown in Figure 5 together.In addition it is possible to use process measurement replaces Error in the calculating of ratio or differential component.More generally, communication stack 80 can include or comprise any software, hardware or solid Part (or its combination in any) is with any field apparatus implemented with include in process 101, process controling element etc. outside controller The communication interface of process 101.

As further example, Fig. 6 exemplified with Process Control System 600, its similar in nature to above in regard to Those described in Figure 4 and 5, because it implements the communication block 135 that controls as above, but are being included in controller 100 and are activating Between device 102 and between transmitter 106 with controller 100 wired communication path (or other are Tong Bu, periodically or without prolonging Slow communication path) Control system architecture in carry out.In the system of Fig. 6, the wave filter 116 updated continuously can directly connect Connect to receive implicit actuator value, it is possible to connect and be supplied directly to summer 112 to output it.Additionally, from pick-up The process variable measurement of device 106 can be directly connected to summer 108.Here, control communication block 135 can be provided to send out to reduce The quantity of controller renewal (control signal) delivering to actuator 102 moves to reduce actuator.Thus, as shown in Figure 6, control Communication block 135 can be shown in reduce in wired or undelayed communication network in many cases in manner described above operation " swing " phenomenon arrived, and/or reduce other of actuator 102 and too much move, even if that synchronize, periodically or without postponing Control and feedback communication in the presence of.In another situation the most unshowned, control communication block 135 and may be used for There is provided between transmitter or sensor and controller radio communication (and thus potential slowly, asynchronous, postpone or non- Periodically communication), and between controller with the actuator controlled in loop, provide wired (or Tong Bus, periodic Or undelayed) in the situation that communicates.

Although it addition, control communication block 135 be shown in controller block 100, but control communication block 135 (or therewith Relevant function) can controller output end with receive the aperiodicity controller output that block 135 produces controlled plant it Between any enforcement.Such as, during block 135 may be embodied in control loop or along after calculating PID output and in cause Dynamic device or other controlled plants receive this signal before any point in control signal path.Such as, the aperiodicity control of block 135 System communicates in the IOB after may be embodied in PID controller, in gateway device or is arranged on controller and controlled cause In any other equipment in control signal communication path between dynamic device.If desired, this function even can be Actuator self is implemented.

Utilize aperiodicity as herein described control communication block 135 it is critical only that use is based on implicit valve location Positive feedback network is implemented PID reset and is calculated, and implicit valve location is preferably sent to controller with the minimum delay from actuator. In theory, the feedback of implicit valve location (i.e. valve actuator receives and works the target location reached) can be by wireless Actuator sends back radio network gateway in response to target location write request.This system figure 7 illustrates.Specifically, such as Fig. 7 Shown in, in operation, controlling communication block 135 will include that the write request of new control target is via as shown in dotted line 200a Wireless path (such as delay or asynchronous communication link) is sent to wireless actuator 102.Hereafter, connect when wireless actuator 102 When receiving new control signal or target, block 135 is responded (shown in dotted line 200b by wireless actuator 102 with write response Wireless link), write response instruction actuator 102 receive control signal.Write response is substantially the reception of control signal Confirm.Additionally, (to write request) write response can reflect control or the desired value of acceptance.After receiving write response, block 135 Implicit actuator position can be changed into by the control signal sent in write request or by instruction in write response The position indicated by desired value accepted.Control block 135 thus can relate to implicit actuator position is sent to Fig. 4's-6 Wave filter 116, for use as implicit actuator position.Certainly, write request or write response form are approved really so that being used in control Any equipment in communication link between device and actuator is implemented, such as gateway device (gateway 73 of such as Fig. 3).

In some embodiments of radio communication, receive order to change target location and actuator at actuator 102 Response sends back and can be by there is significantly delay between controller (or block 135) acquisition.In the case, by block The operation of 135 carrys out restriction controller and sends new control signal, until after actuator receives confirmation.So that controller 100 can compensate this notable and variable delay in the radio communication of write response automatically, it is possible to use new control letter Number form is to support to use the control of the such as wireless actuator of wireless valve actuator.

Specifically, application time field can be added to control when control output valve is sent to wireless actuator In signal.This field can specify the time that when output valve should come into force or should be implemented by actuator in the future.Preferably, should set Determine time delay so that obtaining output communication and the reading back to communicate and all complete before this future time to controller of actuator. In other words, in the future actuator to implement to change time of the movement to realize control signal desired value preferably equal to or More than the time of predicted delay, wherein, it is contemplated that postpone by the new control signal of block 135 to the transmission of actuator and/or from actuating The device one or both of the transmission to block 135 or to the confirmation of controller 100 or write response is incorporated in communication.But use this to order Order, time specified when can should take action in new target location based on the target location and actuator being sent to actuator Between be precisely calculated implicit actuator position.Such as, if the time specified in the output is the fixing second in the future all the time Number Y, then implicit actuator can be calculated in controller 100, gateway etc. simply by target location being postponed the Y second (or valve) position.Thus, the implicit actuator position of calculating can mate with the desired value in actuator, as long as newly The time delay specified in order, (it was right to be likely to be from actuator reception equal or longer than new target location is sent to actuator The confirmation of the reception of this target) needed for time.Accurately reflect in actuator in order to ensure the implicit actuator position calculated Target location, only just newly output can be issued actuator when receiving the confirmation of last communication.

Thus, in general, newer command can comprise one or more new desired value (S) and actuator or valve answers root According to newly requested and take action time (S).In the case, when valve or actuator receive new request, its meeting Wait until the scheduled time taking action according to fresh target value.But when valve or actuator receive new order, it stands I.e. making great efforts to send response, it comprises and confirms and/or comprise new desired value and (thus confirm to receive and produce new implicit actuating Device position), even if before valve takes action according to new desired value.This order reduces or alleviates and (or uses with block 135 The controller of wave filter 116) receive the problem that the notable implicit actuator position value postponed is relevant, thus carry in these environment Supply more preferable control.It practice, so that the impact of this communication delay is minimum, it is proposed that when performing control with wireless valve Using the order that this is new time processed, the implicit actuator position in the feedback circuit of controller is based on desired value, described Desired value is sent to valve, be delayed by order for action time with buffering fresh target value to be sent to valve Time between time.External reset value in controller thus or calculate in the control module in communication layers, permissible There is provided to be used as PID external reset value (such as arriving the input of wave filter 116) as " implicit valve location ".But arbitrary In the case of, it is intended to wait to send new control command, until the valve received from valve or actuator have been received by sending out Deliver to the confirmation of the former order of valve.

Certainly, the time value in this is ordered can be based on accepting the time of new desired value at block 135 plus pre- The time delay of configuration.Time delay such as can be set by user, structural engineer, manufacturer etc., or can be based on logical The statistical property of letter link (prolong by average retardation, the intermediate value measuring in communication link in such as during special time or observe Late, maximum delay, one or more standard deviations etc. of predicted delays based on multiple delay measurements).

As the example of this operation ordered, Fig. 8 is exemplified with the sequential chart of the multiple signals related in communication process 800, wherein, process AO IOB, to produce, there is the control signal of fresh target value, fresh target value is sent to valve and (or activates Device), subsequently by valve or actuator effect.In the example of fig. 8, line 801 represents by control routine generation and as to control The input of communication block 135 processed and the control signal that provides.Line 802 represents the target being supplied to actuator by control communication block 135 Output or the generation of output control signal.Line 804 represents the reception at actuator of the fresh target value, can correspond to return to controller The transmission of confirmation that received by actuator (valve) of desired value.Line 806 represents that actuator or valve response are in control signal The sequential of operation, arrives the time delay of actuator more than it for the change institute of desired value in line 802 exemplified with control signal The time spent.Last line 808 represents the last valve return received by block 135.Note, due to operation explained above, Block 135 will not send the control signal of new control signal or change, until it receives write response, instruction actuator (valve) connects Receive in front control signal, this be the change in line 808 in time (the most in time) corresponding to new control signal from The change (being indicated by line 802) that block 135 sends.

Under any circumstance, use enable the controller to as part control signal this time delay real with actuator Border simultaneously or almost simultaneously changes for feeding back calculating (such as to move towards new desired value according to control signal action The wave filter 116 stated) in implicit actuator position, prolong even if existing significantly to communicate between controller with actuator Late.This operation makes to control feedback and calculates the most synchronize with the practical operation of valve, thus provides preferably or more The control operation of robust.

Lower Table I provides the exemplary of the wireless position monitor definition for implementing this of concept time delay The definition of WirelessHART custom command.Order shown in Table I by output valve or multiple output valve (in byte 3 and 4 One or more parameters for identifying in byte 0 and 1 define) write monitor (such as actuator), including application time word Section (in byte 6-13).Application time field may indicate that and (such as controls with sending from block 135 from some timestamps specified The timestamp of signal correction) skew or time delay, by the several distinct devices in process control communication network synchronize The absolute time that determines of system clock, from the shift time etc. of system clock.Additionally, if desired, new order can To send multiple control signals at different shift times or simultaneously or in a sequence to apply in the same offset time.The quantity of order Such as can the second shown in tablei byte provide.

Table I

Under any circumstance, control to use this data form cause or be equivalent to have zero for valve or other actuators Read back or confirm to postpone, as long as control system and wireless network have the common recognition for this time ordered or measurement, in life The time delay specified in order is more than write request and the one way of write response or round-trip delay.

Perform two groups of tests to show control as herein described and the function of communication system.First group of test supposes that minimum is rung Should (confirmation) postpone to carry out, second group of test includes that notable operating lag is carried out, and notable operating lag uses as mentioned above The application time concept of the part as control signal alleviate.Each test as herein described uses the process of emulation Control system performs.

In the test group using minimum response to postpone, carry out 8 tests altogether and use the non-of wireless valve to show The PID control of periodical communication is the effective means of the quantity of the communication being reduced to valve.Create control, communication and process response Emulation with allow by have be sent to wireless valve aperiodicity control communication control system performance with use wired The traditional PID control system of valve compares.In these tests, include significantly prolonging in the communication from controller to valve Late, but with the minimum delay receive valve receive message confirmation.Process gain tests phases with dynamic and PID regulation for these 8 With, used as described below.

In these each tested, introduce identical set point change (10%) and immeasurablel load disturbance becomes Change (10%).Table II summarizes test condition.

Table II

Table III summarizes the result of these tests.

* the wireless transmitter being used together with wireless valve

Table III

(i.e. based on the implicit valve location transmitted by wireless valve reset calculates to use the change in the PID proposed And use the aperiodicity communication of wireless valve), can greatly be reduced to the quantity of the communication of valve, such as institute in Table III Show.In most cases, control performance is still acceptable.Response during test 4 is in the curve chart 900 of Fig. 9 Illustrate, be typically seen in these test processs.Specifically, first group of line of curve chart 900 represents set-point value 901, use the controlled variable 902 (there is control as herein described and communication process) of the measurement of wireless valve acquisition and use The controlled variable 903 (and typical PID control routine) of the measurement that wired valve obtains.Second group of line represents for wireless valve Valve move or valve location 910 (using control as herein described and communication process) and for the valve location of wired valve 911 (using typical PID control routine).Beneath line 915 is in order at the immeasurablel interference that emulation purpose introduces.Cause And, curve chart 900 represent in response to two set point change and during immeasurablel interference for test 4 use this Control described in literary composition and the comparison performance controlling loop of communication process.

Additionally, as further test, revise the control performed in more above-mentioned tests and communication simulation be new to utilize Control signal data form, it allows the logical of notable communication delay between controller and valve and valve response or confirmation Notable delay in letter.The feedback path between actuator and controller is used to include this amendment of notable communication delay Emulate test 9-12.With in the past test uses identical process gain and dynamically and controller regulation is for these volumes Outer test.

Test 9 and 10 in, wired measuring with wireless valve compared with wired measuring and wired valve.Test 11 Hes In 12, wireless measurement with wireless valve compared with wired measuring and wired valve.In these test processs, by set point and Change identical in immeasurablel interference introduces two and controls in loop.Show in table iv so that valve moves, to valve The setting that the communication delay of door communicates with the aperiodicity of the communication delay minimum in valve response.

Table IV

Table V summarizes and has the use of wire transmitter and valve to wireless valve relative to what the typical PID of use controlled The result acquired by controlled in wireless of the amendment of door.

Table V

Test result is combined based on external reset exemplified with the new outputting data signals form proposed by use The implicit valve location calculated, so that the impact of communication delay is minimum.For using set point and the load of wireless valve Change in interference observes stable control.In valve target, the quantity of change decreases 23 times.During test 10 Response, shown in the curve chart 1000 of Figure 10, is typically seen in these test processs.In curve chart 1000 first Group line represents set-point value 1001, uses the controlled variable 1002 of the measurement of wireless valve (have control as herein described and lead to Letter process) and use the controlled variable 1003 (and typical PID control routine) of wired valve.Second group of line represents for nothing The valve of line valve moves or valve location 1010 (having control as herein described and communication process) and for wired valve Valve location 1011 (using typical PID control routine).Beneath line 1015 is immeasurablel interference.Thus, curve chart 1000 represent in response to two set point change and during immeasurablel interference for test 10 use described herein Control and communication process control loop comparison performance.

Test as another, use WirelessHART module to serve as sensor in laboratory environment and actuator comes Emulation WirelessHART network.Simulation process runs in inside modules with associated sensor and the value of actuator.Owing to using Actual wireless network, it is believed that this experiment very closely illustrates the application in real world.

In order to be more fully understood that this experiment, explanation is had the DCS (dcs) of WirelessHART network Associated component and in order to perform experiment amendment that it is made.Specifically, test DCS includes using is the complete of input equipment The WirelessHART network of portion's WirelessHART equipment.Equipment by data publication to gateway, gateway caches data and based on Request forwards the data to main frame.In DCS system used, it is referred to as PIO with the assembly of gateway call.Control including PID Module is conversed with PIO.As long as gateway can not send asked response, gateway is just to postpone response (DR) state to from PIO Any other request make an immediate response.Gateway forwards requests to the controlled plant in WirelessHART network subsequently.Thus, PIO must cross-question gateway, be repeatedly available DR, until received the response from controlled plant by gateway, gateway subsequently without Reply DR signal.This mechanism is applicable to the output of actuator write.But it may happen that in the future WirelessHART standard can allow the request unconfirmed from PIO to equipment, i.e. downstream to issue.

In PIO in this experiment, implementation of class is similar to above in relation to the control communications component described in block 135.It addition, HART write order is for using above-mentioned application time concept that output is write valve.So that with have delay or application time Between the HART command of assembly change the target valve position that kept by wireless valve.If the target valve position specified in order Put the different value included in the former change request being and issue gateway, then this order is regarded as new asking Ask.If gateway is front receiving the response of the wireless valve to the change in the position of last-minute plea, then gateway is with regard to root According to new change request operation.Otherwise, new change is asked by gateway buffers.In order to ensure use nearest PID output and with Minimum delay is sent to valve, controller (PIO block) the aperiodicity communication scheme implemented is in accordance with following condition:

(1) PID block to perform the time needed for new desired value being sent to valve than gateway and receives response faster.

(2) PID performs (once per second or faster) each time, changes request command and is sent to PIO.If it is but identical Order (identical desired value) is sent to PIO, then be returned to related valve response.AO block READ_BACK parameter reflects Associated target value.

(3) if the state of AO block READ_BACK parameter changes into Bad Communication Failure, then phase Same change request continues to be sent to gateway and is considered as new order.

Table VI illustrates exemplified with the change in the PID output after applying aperiodicity to control communication block in this experiment The traffic diagram changed.

Table VI

As shown in Table VI, in step 2, new change request is sent by controller AO/Out block and PIO with by desired value Change into 50.The summary responses of gateway are replied with DR (postponing response) signal.After one second, in step 4, identical change request Again issue gateway.In step 6, HART command is issued valve (changing the valve target at valve) by gateway subsequently, but does not has Receive reply (write response), until step 9.But in step 8, the time delay to valve provided in original control command After, in AO/READBACK value, reflection changes request, with the valve position being used as to imply in the PID positive feedback network of controller Put.In step 11 (again sending control command in response in step 10), valve return to the target valve of gateway (step 9) Position returns to PIO.Hereafter, in PID output, new change is sent by PIO in step 12, the most as shown in Table VI.

If as it is assumed that the communication from gateway to valve is lost after step 6, then over time, valve rings The loss answered will be detected by gateway, and in response to next controller write request, can indicate this failure.This failure with After can be changed into Bad Communications (invalid communication) by AO/READBACK state and indicate.After the detection of communication Next controller is written on and is regarded as new write request.But AO/READBACK may proceed to show Bad Com (invalid communication) shape State, until receiving response in response to the change request repeated from valve.

In general sense, can also answer above in relation to the controller described in the control of use wireless valve or PID amendment In the PID controller using wired valve, in order to make valve by reducing the frequency of the change in target valve position Door abrasion minimum.In order to tackle this application, aperiodicity communication function can cover in PID or I O function block, implicit Valve location can be based on the control signal value of output to valve.Additionally, for determining whether the PID output of calculating should be sent to The criterion of wireless valve can also include or consider the speed that the controller output calculated changes.In some cases, this is special Point can allow the reaction that faster immeasurablel process is disturbed.Yet further, control as aperiodicity as herein described The part of communication function, filtering can be applied to the control output calculated before applying control communication criteria as herein described.With Determine whether to transmit new controlling value.Similarly, the quantity of change in display valve location and the tolerance of total valve stroke May be embodied in control system, such as in radio network gateway, wireless valve etc., to determine that aperiodicity controls communication and reducing Effectiveness in the frequency of change in target valve position.

As a universal problem, the practice of control technology as herein described is not limited to and single input, single output PID control Routine processed (can not P, PI and PD routine) is used together, but can apply to multiple different multi input and/or multi output controls In scheme, in cascade Mach-Zehnder interferometer scheme or other control programs.More generally, control technology as herein described can also be applied to appoint In the environment of the System design based on model routine of what closed loop (such as Model Predictive Control routine), be directed to use with or generate one or Multiple the output of process variablees, one or more process input variables or other control signals.

Term " field apparatus " is used (that is, to carry with the combination including multiple equipment or equipment herein on wide significance For the equipment of multiple functions, such as transmitter/actuator mixing), and any other of the function in executive control system set Standby.Under any circumstance, field apparatus such as can include that (such as, such as offer represents such as temperature, pressure to input equipment The sensor of the state of the process control parameters of power, flow velocity etc., measurement or other signals and the equipment of instrument), and control behaviour Author or actuator, it is in response to from controller and/or other field apparatus of such as valve, switch, flow-control equipment etc. Receive order and perform operation.

It should be noted that any control routine as herein described or module can have with the distributed way on multiple equipment The part being practiced or carried out.As a result, control routine or module can have by different controllers, field apparatus that (such as intelligence is existing Field device) or other equipment or control element implement part, if it is desired to like this.Similarly, described herein as in mistake Any control routine or the module implemented in process control system can be to take any form, including software, firmware, hardware etc..Carry May be generally referred to as " control element " herein for any equipment involved by this function or element, the most associated is soft Whether part, firmware or hardware are arranged on the controller in Process Control System, field apparatus or any other equipment (or equipment Set) in.Control module, routine or block can be any parts or the parts of Process Control System, such as include routine, block or Its any element, is stored on any computer-readable medium to perform on a processor.This control module, control routine Or its any part (such as block) can be come by any element of Process Control System or equipment that collectively referred to herein as control element It is practiced or carried out.Control routine can be the part (example of module or any part of control program, such as subroutine, subroutine Such as code line) etc., can implement with any desired software format, such as, use OOP, use trapezoidal patrolling Volume, SFC, functional-block diagram, or use programming language or the design pattern of any other software.Similarly, example is controlled Journey can be hard coded into the most one or more EPROM, EEPROM, special IC (ASIC) or any other hardware or solid In part element.Further, control routine can use any design tool to design, including graphic design tool or any The programming of other kinds of software/hardware/firmware or design tool.Therefore, controller 11 as herein described can be configured to Any desired mode implements control strategy or control routine.

Alternately or in addition, functional device can be stored in field apparatus self and be implemented by them, or in mistake Other of process control system control in element, and they can be the situation of the system utilizing Fieldbus equipment.Although it is the most total Use functional device control strategy to provide the explanation of control system on body, but this control technology and system can also use other normal Rule convention is implemented or designs, such as ladder logic, SFC etc., or uses any other desired programming language Or normal form.

When implementing, any software as herein described can be stored in any computer-readable memory, such as disk, In laser disk or RAM or ROM of other storage mediums, computer or processor, flash memory etc..Similarly, this software can make Consign to user, processing factory or operator workstation with any of or desired delivery method, such as, be included in calculating Machine can be in disk-read or other portable computer storage mechanism or by communication channel, such as telephone wire, the Internet, Wan Wei Net, other LAN or wide area networks etc..And, this software directly can provide without modulation or encryption, or can be logical Cross and before communication channel transmits, use any applicable modulation carrier wave and/or encryption technology modulation and/or encryption.

Thus, although illustrating the present invention with reference to particular example.But its intention is merely illustrative, not to the present invention's Limit, for it will be obvious to one of ordinary skill in the art that without departing from the spirit and scope of the present invention, permissible Control technology as herein described is made a change, adds or deletes.

Claims

1. the method using controlled plant in control signal control process, including:

Process controller calculating equipment is implemented the successive ignition of control routine, with the iteration each time at described successive ignition Period generates the control signal value for controlling described controlled plant；And

During the iteration each time of the successive ignition of described control routine, calculate equipment being coupled to described process controller Implement Communications routines in computer-processing equipment, implement described Communications routines and include:

The most pass by during determining minimum predetermined call duration time, and

Determine whether that receiving the described controlled plant of expression from described controlled plant has been received by previous control signal really Recognize；

And, at least pass by during the predetermined call duration time of described minimum, and receive from described controlled plant When representing the confirmation that described controlled plant has been received by described previous control signal, determine further signal transmission conditions Whether it is satisfied；And

Only pass by and received from described controlled plant to be subject to described in expression during the predetermined call duration time of described minimum Control equipment has been received by the confirmation of described previous control signal, and described further signal transmission conditions are satisfied Time, new control signal is sent to described controlled plant via communication link.

Method the most according to claim 1, wherein it is determined that whether described further signal transmission conditions are satisfied bag Include: determine and believe in the control signal value generated for control routine iteration and the described previous control being sent to controlled plant Number value between difference whether more than threshold value.

Method the most according to claim 1, wherein it is determined that whether described further signal transmission conditions are satisfied bag Include: determine from described previous control signal be sent to described controlled plant time whether exceed max-thresholds time value.

Method the most according to claim 1, wherein it is determined that whether described further signal transmission conditions are satisfied bag Include: determine and believe in the control signal value generated for control routine iteration and the described previous control being sent to controlled plant Number value between difference whether more than threshold value；Or determine being sent to described controlled plant from described previous control signal Whether the time exceedes max-thresholds time value.

5. according to the method described in any one in claim 1-4, wherein, it is being coupled to described process controller calculating equipment Computer-processing equipment in implement described Communications routines and include: the changing each time of the iteration that is repeatedly connected of described control routine Described Communications routines is implemented during generation.

6. according to the method described in any one in claim 1-5, wherein, new control signal is sent via communication link To described controlled plant comprise determining that for described control routine iteration described control signal value be sent to controlled plant Described previous control signal value between difference whether more than maximum change threshold, and when for described control routine Difference between the described control signal value of iteration and the value of the described previous control signal that is sent to controlled plant is more than described During maximum change threshold, send the constrained form as the described control signal value for described control routine iteration, described New control signal.

7. according to the method described in any one in claim 1-6, wherein, by described new control signal via communication link It is sent to described controlled plant include: via wireless communication link, described new control signal is sent to described controlled plant.

8. according to the method described in any one in claim 1-6, wherein, by described new control signal via communication link It is sent to described controlled plant include: via wired communications links, described new control signal is sent to described controlled plant.

9. according to the method described in any one in claim 1-8, wherein, by described new control signal via communication link Be sent to described controlled plant include: send as new control signal value and at described controlled plant implement described newly Control signal value time, described new control signal.

Method the most according to claim 9, wherein, sends the described time for implementing described new control signal value Including: send the described time as shift time.

11. methods according to claim 9, wherein, send the described time for implementing described new control signal value Including: send the described time as absolute time.

12. according to the method described in any one in claim 1-11, wherein, implements control on process controller calculating equipment The successive ignition of routine processed includes: implement ratio, integration, derivative-type control routine.

13. methods according to claim 12, wherein, implement described ratio, integration, derivative-type control routine include: make Described control signal value is generated by the feedback signal of the attribute representing described controlled plant.

14. according to the method described in any one in claim 12-13, wherein, by described new control signal via communication Link is sent to described controlled plant and includes: send new control signal value and at described controlled plant implement described newly Scheduled time of control signal value, and wherein, use described feedback signal to include: to assume that described controlled plant is for reality The described scheduled time executing described new control signal value implements described new control signal value, to determine described feedback letter Number.

15. according to the method described in any one in claim 13-14, farther includes to receive institute via wireless communication link State feedback signal.

16. according to the method described in any one in claim 13-14, farther includes to receive institute via wired communications links State feedback signal.

The Process Control System of 17. 1 kinds of controlled plants in using control signal control process, including:

Process controller, described process controller storage control routine, and during successive ignition, implement described control routine, with The control signal value for controlling described controlled plant is generated during the iteration each time of described successive ignition；And

The Communications routines implemented in being coupled to the computer-processing equipment of described process controller, wherein, described communication example Control signal value that journey receives the iteration each time of the successive ignition for described control routine, that generated, and perform described Communications routines with:

And, perform described Communications routines further, at least to pass by during the predetermined call duration time of described minimum, and In time receiving, from described controlled plant, the confirmation that the described controlled plant of expression has been received by described previous control signal, really Whether fixed further signal transmission conditions are satisfied；And

18. Process Control Systems according to claim 17, wherein, described Communications routines determines institute in the following way State whether further signal transmission conditions are satisfied: determine the described control signal generated for described control routine iteration Whether the difference between value and the value of the described previous control signal that is sent to controlled plant is more than threshold value.

19. Process Control Systems according to claim 17, wherein, described Communications routines determines institute in the following way State whether further signal transmission conditions are satisfied: determine being sent to described controlled plant from described previous control signal Time whether exceed max-thresholds time value.

20. Process Control Systems according to claim 17, wherein, described Communications routines determines institute in the following way State whether further signal transmission conditions are satisfied: determine at the described control letter generated for described control routine iteration Whether the difference between the value of the described previous control signal number being worth and be sent to controlled plant is more than threshold value, or determines from institute State previous control signal and be sent to whether the time that described controlled plant rises exceedes max-thresholds time value.

21. according to the Process Control System described in any one in claim 17-20, and wherein, described Communications routines is by institute The computer-processing equipment stated in process controller is implemented.

22. according to the Process Control System described in any one in claim 17-21, and wherein, described Communications routines determines Value for described control signal value and the described previous control signal being sent to controlled plant of described control routine iteration Between difference whether more than maximum change threshold, and when for described control routine iteration described control signal value with send out When difference between the value of the described previous control signal delivering to controlled plant is more than described maximum change threshold, generate as using In described control routine iteration control signal constrained form, described new control signal

23. according to the Process Control System described in any one in claim 17-22, and wherein, Communications routines is by described new Control signal is sent to described controlled plant as wireless communication signals.

24. according to the Process Control System described in any one in claim 17-23, and wherein, described Communications routines is by described New control signal is generated as including new control signal value and for implementing described new control letter at described controlled plant Number value time.

25. Process Control Systems according to claim 24, wherein, for implementing the described of described new control signal value Time is shift time.

26. Process Control Systems according to claim 24, wherein, for implementing the described of described new control signal value Time is absolute time.

27. according to the Process Control System described in any one in claim 24-26, and wherein, described control routine uses table Show the feedback signal of attribute of described controlled plant to generate described control signal value, and described control routine is used in generation During the described control signal of control routine iteration at least one times, it is assumed that described controlled plant implements described with the described scheduled time New control signal value, so that it is determined that described feedback signal.

28. according to the Process Control System described in any one in claim 17-27, wherein, described control routine be ratio, Integration, derivative-type control routine.

29. according to the Process Control System described in any one in claim 17-28, wherein, described control routine be ratio, Integration, differential (PID) type control routine, and wherein, described process controller receives at described PID via wireless communication link Type control routine is used as the feedback signal of feedback signal.

30. 1 kinds of Process Control Systems being used for the process that controls, including:

Process controller, described process controller includes one or more processor, memorizer and communication interface；

Communication link；And

Controlled plant, described controlled plant is arranged in described process, and is communicably coupled to institute via described communication link State process controller；

Wherein, described process controller includes the control routine being stored on described memorizer, and described control routine is repeatedly changing Perform on the one or more processors during the iteration each time in generation, to generate the control for controlling described controlled plant Signal value processed, and

Wherein, described communication interface includes the interface program being stored on described memorizer, and described interface program is in one Or perform on multiple processor with:

(1) determine from previous control signal is sent to described controlled plant, whether has already been through the minimum phase scheduled time Between,

(2) determine whether to receive from described controlled plant and represent that described controlled plant has been received by described previous control letter Number confirmation；

(3) determine whether to meet further signal transmission conditions；And

Wherein, from described previous control signal is sent to described controlled plant, minimum pre-timing is had already been through when (1) During between；(2) receive the described controlled plant of expression from described controlled plant and have been received by described previous control letter Number confirmation；And (3) described further signal transmission conditions are when being satisfied, described interface program is based on by described control example New control signal is sent to described by the described control signal value that journey is generated during iteration via described communication link Controlled plant, and when (1) makes a reservation for through minimum from described previous control signal is sent to described controlled plant During time；Or (2) do not receive from described controlled plant that to represent that described controlled plant has been received by described previous The confirmation of control signal；Or when (3) described further signal transmission conditions are not satisfied, described interface program be not based on by The described control signal value that described control routine is generated during iteration by new control signal via described communication link It is sent to described controlled plant.

31. Process Control Systems according to claim 30, wherein, if generated for described control routine iteration Described control signal value and the value of the described previous control signal that is sent to controlled plant between difference more than threshold value, then institute State interface program and determine that described further signal transmission conditions are satisfied.

32. Process Control Systems according to claim 30, wherein, if being sent to institute from described previous control signal Stating the time that controlled plant rises has exceeded max-thresholds time value, and the most described interface program determines that described further signal transmits Condition is satisfied.

33. Process Control Systems according to claim 30, wherein, if generated for described control routine iteration Described control signal value and the value of the described previous control signal that is sent to controlled plant between difference more than threshold value；Or From described previous control signal be sent to described controlled plant time exceeded max-thresholds time value, the most described interface Routine determines that described further signal transmission conditions are satisfied.

34. according to the Process Control System described in any one in claim 30-33, and wherein, described interface program is further Determine and believe with the described previous control being sent to controlled plant in the described control signal value for described control routine iteration Number value between difference whether more than maximum change threshold, and when in the described control signal for described control routine iteration When difference between value and the value of the described previous control signal that is sent to controlled plant is more than described maximum change threshold, create As the control signal for described control routine iteration constrained form, described new control signal.

35. according to the Process Control System described in any one in claim 30-34, and wherein, described communication link is wireless Communication link.

36. according to the Process Control System described in any one in claim 30-34, and wherein, described communication link is wired Communication link.

37. according to the Process Control System described in any one in claim 30-36, and wherein, described interface program is by new Control signal is created as including desired value and for implementing the signal of the time of described desired value at described controlled plant.

38. according to the Process Control System described in claim 37, wherein, is inclined for implementing the described time of described desired value Shift time.

39. according to the Process Control System described in any one in claim 30-38, wherein, described control routine be ratio, Integration, differential (PID) type control routine.

40. according to the Process Control System described in any one in claim 30-39, and wherein, described control routine uses table Show that the feedback signal of attribute of described controlled plant is to generate described control signal value.

41. Process Control Systems according to claim 40, wherein, described control routine uses and represents that the process recorded becomes The extra feedback signal of amount generates described control signal value.

42. according to the Process Control System described in any one in claim 30-41, and wherein, described interface program is by new Control signal is created as including desired value and for implementing the signal of the time of described desired value at described controlled plant, and Wherein, described control routine uses the attribute of described controlled plant to generate described control signal value, and wherein, described control Routine assumes that described controlled plant implements described desired value for the described time implementing described desired value, described to determine The attribute of controlled plant.

43. according to the Process Control System described in any one in claim 30-43, farther includes sensor and other Communication link, it is interior to measure process variable that described sensor is arranged on described process, and described other communication link is arranged on institute Stating between process controller and described sensor, wherein, described control routine uses the described process recorded by described sensor Variable determines described control signal value.

44. according to the Process Control System described in any one in claim 30-43, wherein, and described communication link and described Other communication link is all wireless communication link.

45. according to the Process Control System described in any one in claim 30-43, wherein, and described communication link and described Other communication link is all wired communications links.

46. according to the Process Control System described in any one in claim 30-43, and wherein, described communication link is wired Communication link, described other communication link is wireless communication link.

47. according to the Process Control System described in any one in claim 30-43, and wherein, described communication link is wireless Communication link, described other communication link is wired communications links.

The process controller of 48. 1 kinds of controlled plants in control process, including:

Processor；

Memorizer；

Process control routine, described process control routine is stored on described memorizer, and changing each time at successive ignition Perform on the processor during generation, to produce the control signal value for controlling the controlled plant in described process, and Wherein, described process control routine includes feedback-type control routine, and it uses the attribute of described controlled plant as feedback variable To generate described control signal value；And

Communications routines, described Communications routines is stored on described memorizer, and during the one or many iteration of successive ignition Perform on the processor, based on described control signal value new control signal is sent to described controlled plant, wherein, Described new control signal includes for the desired value of described controlled plant with for implementing the time of described desired value；

Wherein, during the one or many iteration of described successive ignition, described process control routine assumes described controlled plant Implement described desired value for the time implementing described desired value, and the attribute of described controlled plant is defined as described instead Feedback variable.

49. process controllers according to claim 48, wherein, described process control routine is connecing from described controlled plant Before receiving the instruction recording property value of described controlled plant, it is assumed that described controlled plant for implement described desired value time Between implement described desired value, and the attribute of described controlled plant is defined as described feedback variable.

50. according to the process controller described in any one in claim 48-49, and wherein, described process control routine is ratio Example, integration, derivative-type control routine.

51. according to the process controller described in any one in claim 48-50, and wherein, described process control routine uses Described feedback variable determines that the reset to described control signal value is contributed.

52. according to the process controller described in any one in claim 48-51, wherein, described Communications routines by described newly Control signal be sent to described controlled plant via wireless communication link.

53. according to the process controller described in any one in claim 48-52, wherein, for implementing described desired value The described time is shift time.

54. according to the process controller described in any one in claim 48-52, wherein, for implementing described desired value The described time is absolute time.

The method of 55. 1 kinds of controlled plants used in control signal control process, including:

Process controller calculating equipment is implemented the successive ignition of control routine, with the iteration each time at described successive ignition Period generates the control signal value for controlling described controlled plant, farther includes to use the attribute conduct of described controlled plant Feedback variable, generates described control signal value during the iteration each time at the described successive ignition of described control routine；

Generate the new control signal of the one or many iteration for described successive ignition, wherein, described new control signal Including the desired value for described controlled plant with for implementing the time of described desired value；And

Described new control signal is sent to described controlled plant by communication link；And

During the one or many iteration of the described successive ignition further including at described control routine, it is assumed that described controlled set The standby time for the described desired value of enforcement implements described desired value, and is defined as by the attribute of described controlled plant described Feedback variable.

56. methods according to claim 55, where it is assumed that described controlled plant for implement described desired value time Between implement described desired value, and the attribute of described controlled plant is defined as described feedback variable and includes: described the most program control Device processed calculates at equipment, before the instruction recording property value receiving described controlled plant from described controlled plant, it is assumed that The controlled plant described in iteration at least one times of described successive ignition implements described for the time implementing described desired value Desired value, and the attribute of described controlled plant is defined as described feedback variable.

57. according to the method described in any one in claim 55-56, wherein, implements control routine and includes enforcement ratio, amasss Point, derivative-type control routine.

58. according to the method described in any one in claim 55-57, farther includes to use described feedback variable to determine Reset to described control signal value is contributed.

59. according to the method described in any one in claim 55-58, wherein, by described new control signal by communication Link is sent to described controlled plant and includes: send described new control signal via wireless communication link.

60. according to the method described in any one in claim 55-59, wherein, generates new control signal and includes: generates and uses Time in the described desired value of enforcement, as shift time.

61. according to the method described in any one in claim 55-59, wherein, generates new control signal and includes: generates and uses Time in the described desired value of enforcement, as absolute time.