CN203433387U - Piping and instrument diagram (PID)-based frequency-conversion and speed-regulation cooling control system - Google Patents
Piping and instrument diagram (PID)-based frequency-conversion and speed-regulation cooling control system Download PDFInfo
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- CN203433387U CN203433387U CN201320481464.XU CN201320481464U CN203433387U CN 203433387 U CN203433387 U CN 203433387U CN 201320481464 U CN201320481464 U CN 201320481464U CN 203433387 U CN203433387 U CN 203433387U
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Abstract
The utility model discloses a PID-based frequency-conversion and speed-regulation cooling control system, wherein the working temperature of a transformer (7) is measured by means of a temperature sensor (6-1) and the working current of the transformer (7) is measured by means of a current sensor (6-2). The temperature sensor (6-1) is connected with a temperature transmitter (5-1). The current sensor (6-2) is connected with a current transmitter (5-2). The temperature transmitter (5-1) and the current transmitter (5-2) are connected with a PID controller (4). A power supply (1), a frequency-conversion speed regulator (2) and a cooling blower (3) are connected in sequence. The PID controller (4) is connected with the frequency-conversion speed regulator (2). In this way, the output power of the frequency-conversion speed regulator (2) can be adjusted by the PID controller (4) according to the working temperature and the working current of the transformer (7), so that the rotating speed of the cooling blower (3) can be adjusted.
Description
Technical field
The utility model relates to a kind of cooling control system, relates in particular to a kind of PID frequency control cooling control system.
Background technology
In prior art Zhong，Dui 35-500kV transformer station, the cooling motor of power transformer does not have speed-regulating function: when transformer temperature is high, and cooling electric chance OnNow; When transformer temperature reaches or during lower than setting value, cooling blower can be out of service, so not only shortened the serviceable life of blower fan, and power consumption is larger, increased virtually the production cost of enterprise.
Therefore, be desirable to provide a kind of cooling control system that can reduce enterprise's production cost.
Summary of the invention
For this reason, the utility model proposes a kind of New PID frequency control cooling control system of at least a portion that can address the above problem.
According to an aspect of the present utility model, a kind of PID frequency control cooling control system is provided, comprise power supply, cooling blower, it is characterized in that: further comprise variable-frequence governor, PID controller, temperature transmitter, temperature sensor, current transducer and current sensor
Wherein, the working temperature of described temperature sensor measurement transformer, the working current of transformer described in described current sensor measurement;
Described temperature sensor is connected with described temperature transmitter, and described current sensor is connected with described current transducer, and described temperature transmitter is all connected with described PID controller with described current transducer,
Described power supply, described variable-frequence governor and described cooling blower are connected successively, described PID controller is connected with described variable-frequence governor, thereby described PID controller regulates the output power of described variable-frequence governor according to the described working temperature of described transformer and described working current, and then regulate the rotating speed of described cooling blower.
Alternatively, according to an embodiment of the present utility model, it is characterized in that: described power supply further comprises direct supply, the first AC power and the second AC power,
Described PID frequency control cooling control system further comprises three power switchers,
One end of described three power switchers is connected with described direct supply, described the first AC power and described the second AC power respectively, and the other end is connected with described variable-frequence governor.
Alternatively, according to an embodiment of the present utility model, it is characterized in that: described cooling blower further comprises the first cooling blower, the second cooling blower, the 3rd cooling blower and the 4th cooling blower.
Alternatively; according to an embodiment of the present utility model, it is characterized in that: described PID frequency control cooling control system further comprises the first motor protecter being connected with described the first cooling blower, the second motor protecter being connected with described the second cooling blower, the 3rd motor protecter being connected with described the 3rd cooling blower and the 4th motor protecter being connected with described the 4th cooling blower.
The PID frequency control cooling control system that the utility model provides at least can reduce power consumption, and reduces the production cost of enterprise.
Accompanying drawing explanation
By reading below detailed description of the preferred embodiment, various other advantage and benefits will become cheer and bright for those of ordinary skills.Accompanying drawing is only for the object of preferred implementation is shown, and do not think restriction of the present utility model.And in whole accompanying drawing, by identical reference symbol, represent identical parts.Wherein in the accompanying drawings, a plurality of identical parts of alphabetic flag indication after reference number, when these parts of general reference, will omit its last alphabetic flag.In the accompanying drawings:
Fig. 1 shows according to the structural representation of a kind of PID frequency control cooling control system of the present utility model; And
Fig. 2 shows according to the structural representation of the PID frequency control cooling control system of a kind of preferred implementation of the present utility model.
Wherein: power supply 1, variable-frequence governor 2, cooling blower 3, PID controller 4, temperature transmitter 5-1, temperature sensor 6-1, current transducer 5-2, current sensor 6-2.
Embodiment
The utility model provides many applicable creative concepts, and this creativeness concept can be reflected in a large number of in concrete context.The specific embodiment of describing in following embodiment of the present utility model is only as the exemplary illustration of embodiment of the present utility model, and do not form the restriction to the utility model scope.
As shown in Figure 1 according to the structural representation of a kind of PID frequency control cooling control system of the present utility model, a kind of PID frequency control cooling control system, comprise power supply 1, cooling blower 3, it is characterized in that: further comprise variable-frequence governor 2, PID controller 4, temperature transmitter 5-1, temperature sensor 6-1, current transducer 5-2 and current sensor 6-2
Wherein, described temperature sensor 6-1 measures the working temperature of described transformer 7, and described current sensor 6-2 measures the working current of described transformer 7;
Described temperature sensor 6-1 is connected with described temperature transmitter 5-1, and described current sensor 6-2 is connected with described current transducer 5-2, and described temperature transmitter 5-1 is all connected with described PID controller 4 with described current transducer 5-2,
Described power supply 1, described variable-frequence governor 2 and described cooling blower 3 are connected successively, described PID controller 4 is connected with described variable-frequence governor 2, thereby described PID controller 4 regulates the output power of described variable-frequence governor 2 according to the described working temperature of described transformer 7 and described working current, and then regulate the rotating speed of described cooling blower 3.
Variable-frequence governor is power frequency supply (50Hz or 60Hz) to be transformed into the AC power of various frequencies, to realize the equipment of the variable-speed operation of motor, wherein control circuit completes the control to main circuit, rectification circuit is transformed into direct current by alternating current, direct-flow intermediate circuit carries out smothing filtering to the output of rectification circuit, and inverter circuit becomes alternating current by direct current another mistake.According to the classification of main circuit working method, can be divided into voltage frequency converter and current-mode converter; According to on-off mode classification, can be divided into PAM and control frequency converter, pwm cycloconverter and high carrier frequency pwm cycloconverter; According to principle of work classification, can be divided into V/f and control frequency converter, slip frequency controlled frequency converter and vector-control frequency converter etc.; According to purpose classification, can be divided into universal frequency converter, high-performance special converter, high-frequency converter, single-phase frequency converter and three phase converter etc.
PID controller (Proportion Integration Differentiation. proportional-integral derivative controller), is comprised of ratio unit P, integral unit I and differentiation element D.By Kp, the setting of Ki and tri-parameters of Kd.PID controller is mainly applicable to substantially linear and dynamic perfromance time invariant system.
PID controller is backfeed loop parts common in Industry Control Application.This controller compares data and the reference value collected, then this difference for calculating new input value, the object of the input value that this is new is can allow the data of system reach or remain on reference value.Different with other simple control algorithms, PID controller can be adjusted input value according to the occurrence rate of historical data and difference, can make like this system more accurate, more stable.Can prove by the method for mathematics, in the situation that other control methods cause system to have steady state error or process repeatedly, what PID backfeed loop but can keeping system is stable.
Transmitter (transmitter) is the output signal of sensor to be changed into the converter of the signal (or the non electrical quantity that sensor is inputted converts to, and electric signal amplifies simultaneously so that the signal source of measuring and controlling for a distant place) that can be identified by controller.Sensor and transmitter together form the monitor signal source of automatic control.Different physical quantitys needs different sensors and corresponding transmitter.The kind of transmitter is a lot, and the transmitter being used in above industrial control instrument mainly contains temperature transmitter, pressure unit, flow transmitter, current transducer, voltage transmitter etc.
Temperature sensor (temperature transducer) refers to the sensor that can experience temperature and convert usable output signal to.Temperature sensor is the core of temperature measuring instrument, various in style.By metering system, contact and contactless two large classes be can be divided into, according to sensor material and electron component characteristic, thermal resistance and thermopair two classes are divided into.
Current sensor is a kind of pick-up unit, can experience the information of tested electric current, and the information that detection can be experienced, be for conversion into according to certain rules and meet the electric signal of certain standard needs or the output of the information of other desired forms, to meet the requirements such as transmission, processing, storage, demonstration, record and control of information.
In prior art Zhong，Dui 35-500kV transformer station, the cooling motor of power transformer does not have speed-regulating function: when transformer temperature is high, and cooling electric chance OnNow; When transformer temperature is during lower than setting value, cooling blower can be out of service, so not only shortened the serviceable life of blower fan, and power consumption is larger, increased virtually the production cost of enterprise.PID frequency control cooling control system provided by the invention can be according to the working temperature of transformer 7 and working current, regulate in real time the rotating speed of described cooling blower 3, thereby avoided cooling blower suddenly open or suddenly stop described in the significantly power consumption that bringing, also reduced the loss to cooling blower, thereby extended the serviceable life of cooling blower simultaneously.
Below in conjunction with accompanying drawing, the utility model is done to explain further:
As shown in Figure 1, a kind of PID frequency control cooling control system, comprise power supply 1, cooling blower 3, it is characterized in that: further comprise variable-frequence governor 2, PID controller 4, temperature transmitter 5-1, temperature sensor 6-1, current transducer 5-2 and current sensor 6-2
Wherein, described temperature sensor 6-1 measures the working temperature of described transformer 7, and described current sensor 6-2 measures the working current of described transformer 7;
Described temperature sensor 6-1 is connected with described temperature transmitter 5-1, and described current sensor 6-2 is connected with described current transducer 5-2, and described temperature transmitter 5-1 is all connected with described PID controller 4 with described current transducer 5-2,
Described power supply 1, described variable-frequence governor 2 and described cooling blower 3 are connected successively, described PID controller 4 is connected with described variable-frequence governor 2, thereby described PID controller 4 regulates the output power of described variable-frequence governor 2 according to the described working temperature of described transformer 7 and described working current, and then regulate the rotating speed of described cooling blower 3.
In order further to optimize the technical solution of the utility model, as shown in Figure 2, described power supply 1 further comprises direct supply, the first AC power and the second AC power, described PID frequency control cooling control system further comprises three power switchers, one end of described three power switchers is connected with described direct supply, described the first AC power and described the second AC power respectively, and the other end is connected with described variable-frequence governor 2.The advantage of this scheme is to adopt three-way power power supply, and two-way exchanges the direct current supply of ，Yi road, and automatic/hand switches.Arbitrary road power supply normally can guarantee transformer cooling system normal operation, thereby has improved the reliability of described PID frequency control cooling control system.
In order to save the energy, to reduce the production cost of enterprise, in utility model provided by the invention, described cooling blower 3 further comprises the first cooling blower, the second cooling blower, the 3rd cooling blower and the 4th cooling blower.Being also advantageous in that of this scheme, when a certain cooling blower breaks down, has standby fan to substitute, thereby guarantees the normal operation of described PID frequency control cooling control system.
Described PID frequency control cooling control system further comprises the first motor protecter being connected with described the first cooling blower, the second motor protecter being connected with described the second cooling blower, the 3rd motor protecter being connected with described the 3rd cooling blower and the 4th motor protecter being connected with described the 4th cooling blower.The effect of motor protecter is comprehensively to protect to motor, when motor occurs that overload, phase shortage, stall, short circuit, overvoltage, under-voltage, electric leakage, three-phase imbalance, overheated, bearing wear, rotor are eccentric, and the device of being reported to the police or protecting.
The common type of motor protecter has:
Electrothermal relay: common low capacity alternating current generator, condition of work is good, does not have the occasion of the bad working environments such as frequent starting.
Electron type: detect three-phase electricity flow valuve, setting current value adopts potentiometer or plucking number sign switch, and circuit generally adopts analog, adopts inverse time lag or specified time operating characteristic.Defencive function comprises overload, phase shortage, stall etc., and fault type adopts pilot lamp to show, operation electric weight adopts charactron to show.
Intelligent: detect three-phase electricity flow valuve, protector is used single-chip microcomputer, realizes intelligent motor integrated protection, collects protection, measurement, communication, is shown as one.Setting current adopts numeral to set, and by operator panel buttons, operates, and user can set various parameter corrections at the scene according to motor concrete condition; Adopt charactron as display window, or adopt large-screen lc to show, can support multiple kinds, as ModBUS, ProfiBUS etc., price is relatively high, for compared with important events; High-voltage motor protection at present all adopts Intelligent protection equipment.
Hot protection type: imbed thermal element in motor, protect according to the temperature of motor winding, protect effective; But when capacity motor is larger, need be used in conjunction with current monitoring type, when temperature sharply rises while avoiding motor rotation blockage, due to the hysteresis quality of temperature element, cause motor winding impaired.
Magnetic field temperature test type: imbed magnetic field detection coil and temperature element in motor; according to the variation of the variation of motor internal rotating magnetic field and temperature, protect; major function comprises overload, stall, phase shortage, overheating protection and wear monitoring; defencive function is perfect, and shortcoming is magnetic field detection coil and temperature sensor to be installed at motor internal.
Preferably, the utility model is selected intelligent electric motor protector, the intelligent operation of PID frequency control cooling control system providing to realize the utility model.
In order to make the PID frequency control cooling control system that the utility model provides more meet intellectuality, modern requirement, and realize remote monitoring and control, improve the reliability of this control system simultaneously, preferably, described PID frequency control cooling control system further comprises Programmable Logic Controller, described Programmable Logic Controller respectively with current transducer 5-2 described in described temperature transmitter 5-1, described PID controller 4, described three power switchers, described the first motor protecter, described the second motor protecter, described the 3rd motor protecter is connected with described the 4th motor protecter.
Programmable Logic Controller is programmable logic controller (PLC) (Programmable Logic Controller, PLC), it adopts a class programmable memory, for its internally stored program, actuating logic computing, sequential control, regularly, the user oriented instruction such as counting and arithmetical operation, and by numeral or analog pattern input/output various types of machinery of control or production run.
For guaranteeing when described variable-frequence governor 2 breaks down; cooling motor is normally used; the safe operation of transformer energy; preferably; described PID frequency control cooling control system further comprises bypath system; one end of described bypath system is connected with described three power switchers, and the other end is connected with described the first motor protecter, described the second motor protecter, described the 3rd motor protecter and described the 4th motor protecter respectively.Preferred, described bypath system is also connected with described Programmable Logic Controller, thereby plays the effect of Long-distance Control bypath system operation.Wherein, described bypath system refers in the situation that variable-frequence governor breaks down, and can play substituted role, makes the equipment of the normal operation of whole cooling control system.
In addition, in accompanying drawing 2, main transformer temperature signal refers to the temperature of the transformer that temperature sensor records, the electric current that refers to the described transformer that current sensor records during main transformer current signal, said temperature and electric current are all converted to normal voltage or current signal via temperature transmitter and current transducer respectively, then feed back to described PID controller.
In sum, control and the protection that is mainly used in main transformer cooling motor in 35-500kV transformer station of the present invention.Its principal feature has:
High reliability: adopt three-way power power supply, two-way exchanges the direct current supply of ，Yi road, and automatic/hand switches.Arbitrary road power supply normally can guarantee transformer cooling system normal operation.
Main transformer temperature is controlled more accurate: main transformer temperature, current signal, after sampling change is sent, are delivered to intelligent PID controller, export afterwards as calculated direct current 0-5V(and are directly proportional to main transformer temperature and current signal).
Control variable-frequence governor, make the rotating speed of main transformer fan from zero to real-time follow-up main transformer temperature and curent change rated speed, accomplish that A main transformer temperature or electric current are higher, rotation speed of fan higher B main transformer temperature or current-rising-rate are higher, when rotation speed of fan higher C main transformer temperature or electric current are in a high position for a long time, rotation speed of fan is higher, thereby accurately controls the requirement of main transformer working temperature.
Energy-conservation: to reduce the electric energy that main transformer fan consumes.
Repair and maintenance is convenient: band auto by pass operation function, when fault or maintenance, can be switched to bypass operation by automatic or manual, and conveniently overhaul and reliability is increased.
Intelligent: band communication function, communication distance≤1200m.Can be main transformer temperature, electric current, the startup of each blower fan, stops, working current, voltage, the switching values such as rotating speed and analog quantity upload to background computer, conveniently realize monitoring function.
Electric motor protecting is more perfect, has avoided burning motor.Adopt microcomputer type motor protecter, there is RS485 communication interface, can realize telecommunication.Communication distance≤1200m.Electric motor protecting has defencive function: the emergency protections such as overcurrent, undercurrent, stall, three-phase current unbalance, disconnected phase, overvoltage, under-voltage, electric leakage, short circuit.In addition also has set-up function: can on-the-spotly set load current value, starting time, overpressure value, under-voltage value, undercurrent value, overcurrent actuation time, locked rotor current to the multiple of rated current, leakage current value, address number, the white proportion by subtraction of three-phase current unbalance.
Casing adopts stainless steel to make, and long service life is corrosion-resistant.Shell protection grade IP44.
Major electrical equipment element miniature circuit breaker in case, A.C. contactor, frequency converter, motor protecter, PLC, PID regulator all adopts domestic (joint) quality product of imported product or equal quality.
It should be noted that, element or the equipment such as power supply described in the utility model 1, variable-frequence governor 2, cooling blower 3, PID controller 4, temperature transmitter 5-1, temperature sensor 6-1, current transducer 5-2 and current sensor 6-2, Programmable Logic Controller, what both comprised that prior art provides also comprises what WeiLai Technology provided.
It should be noted, the present invention will be described rather than limit the invention for above-described embodiment, and those skilled in the art can design alternative embodiment in the situation that do not depart from the scope of claims.In the claims, any reference symbol between bracket should be configured to limitations on claims.Word " comprises " not to be got rid of existence and is not listed as element or step in the claims.Being positioned at word " " before element or " one " does not get rid of and has a plurality of such elements.The use of word first, second and C grade does not represent any order.Can be title by these word explanations.
Claims (4)
1. a PID frequency control cooling control system, comprise power supply (1), cooling blower (3), it is characterized in that: further comprise variable-frequence governor (2), PID controller (4), temperature transmitter (5-1), temperature sensor (6-1), current transducer (5-2) and current sensor (6-2)
Wherein, the working temperature of described temperature sensor (6-1) measuring transformer (7), described current sensor (6-2) is measured the working current of described transformer (7);
Described temperature sensor (6-1) is connected with described temperature transmitter (5-1), described current sensor (6-2) is connected with described current transducer (5-2), described temperature transmitter (5-1) is all connected with described PID controller (4) with described current transducer (5-2)
Described power supply (1), described variable-frequence governor (2) and described cooling blower (3) are connected successively, described PID controller (4) is connected with described variable-frequence governor (2), thereby described PID controller (4) regulates the output power of described variable-frequence governor (2) according to the described working temperature of described transformer (7) and described working current, and then regulate the rotating speed of described cooling blower (3).
2. PID frequency control cooling control system according to claim 1, is characterized in that: described power supply (1) further comprises direct supply, the first AC power and the second AC power,
Described PID frequency control cooling control system further comprises three power switchers,
One end of described three power switchers is connected with described direct supply, described the first AC power and described the second AC power respectively, and the other end is connected with described variable-frequence governor (2).
3. PID frequency control cooling control system according to claim 2, is characterized in that: described cooling blower (3) further comprises the first cooling blower, the second cooling blower, the 3rd cooling blower and the 4th cooling blower.
4. PID frequency control cooling control system according to claim 3, is characterized in that: described PID frequency control cooling control system further comprises the first motor protecter being connected with described the first cooling blower, the second motor protecter being connected with described the second cooling blower, the 3rd motor protecter being connected with described the 3rd cooling blower and the 4th motor protecter being connected with described the 4th cooling blower.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320481464.XU CN203433387U (en) | 2013-08-07 | 2013-08-07 | Piping and instrument diagram (PID)-based frequency-conversion and speed-regulation cooling control system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201320481464.XU CN203433387U (en) | 2013-08-07 | 2013-08-07 | Piping and instrument diagram (PID)-based frequency-conversion and speed-regulation cooling control system |
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| CN203433387U true CN203433387U (en) | 2014-02-12 |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104865992A (en) * | 2015-03-26 | 2015-08-26 | 国网河南省电力公司平顶山供电公司 | Direct-current cooling system of main transformer of transformer substation |
| CN106322596A (en) * | 2016-08-23 | 2017-01-11 | 四川科冠电子有限公司 | Intelligent draught fan adopting novel speed controller |
| CN106368976A (en) * | 2016-11-30 | 2017-02-01 | 淮北矿业股份有限公司 | Constant-temperature frequency conversion speed regulator for mine cooling fan |
| CN109404325A (en) * | 2018-12-30 | 2019-03-01 | 河南迪诺环保科技股份有限公司 | A kind of control circuit system of magnetic suspension air blower |
-
2013
- 2013-08-07 CN CN201320481464.XU patent/CN203433387U/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104865992A (en) * | 2015-03-26 | 2015-08-26 | 国网河南省电力公司平顶山供电公司 | Direct-current cooling system of main transformer of transformer substation |
| CN104865992B (en) * | 2015-03-26 | 2017-06-06 | 国家电网公司 | A kind of main transformer of transformer substation once-through cooling system |
| CN106322596A (en) * | 2016-08-23 | 2017-01-11 | 四川科冠电子有限公司 | Intelligent draught fan adopting novel speed controller |
| CN106368976A (en) * | 2016-11-30 | 2017-02-01 | 淮北矿业股份有限公司 | Constant-temperature frequency conversion speed regulator for mine cooling fan |
| CN109404325A (en) * | 2018-12-30 | 2019-03-01 | 河南迪诺环保科技股份有限公司 | A kind of control circuit system of magnetic suspension air blower |
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