CN105424993A - LabVIEW-based programmable current source system and method - Google Patents
LabVIEW-based programmable current source system and method Download PDFInfo
- Publication number
- CN105424993A CN105424993A CN201511016024.7A CN201511016024A CN105424993A CN 105424993 A CN105424993 A CN 105424993A CN 201511016024 A CN201511016024 A CN 201511016024A CN 105424993 A CN105424993 A CN 105424993A
- Authority
- CN
- China
- Prior art keywords
- pressure regulator
- current
- voltage
- coarse adjustment
- transformer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R1/00—Details of instruments or arrangements of the types included in groups G01R5/00 - G01R13/00 and G01R31/00
- G01R1/28—Provision in measuring instruments for reference values, e.g. standard voltage, standard waveform
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Control Of Stepping Motors (AREA)
Abstract
The invention discloses a LabVIEW-based programmable current source system and a method. The system comprises a voltage regulation device, a protection and conversion device and a control device. Through adopting a combination of a coarse and fine voltage regulator group and a transformer, the current regulation precision is greatly improved, and the current regulation range is expanded. Upper computer software can realize acquisition of a current real-time value through LabVIEW language writing and in match with a high-precision data acquisition card, actions of the voltage regulator and a relay are controlled, and the purpose of automatic current regulation are realized. a voltage sensor is adopted to acquire a potential difference between a fine voltage regulator contact and a zero point, return-to-zero reset is carried out according to the size of the potential difference, and reset operation is realized quickly and accurately. The system and the method of the invention have the advantages that the stability is good; the precision is high; the current regulation precision is smaller than 0.5%; the regulation time is around 4s generally; the current regulation range is 0.1A to 1500A; and requirements of a low-voltage electrical apparatus industry test can be well met.
Description
Technical field
Patent of the present invention belongs to virtual instrument technique field, is specifically related to a kind of programmable current source method for designing based on LabVIEW.Can run on a general-purpose computer in particular to a kind of LabVIEW of employing programming, there is the programmable current origin system of interactive interface.
Background technology
Strong current generator is a kind of electric equipment that can provide steady current to load, and the big current that debugging and detection for all trades and professions low-voltage electrical apparatus provide scope adjustable, is widely used in the test of the various protection features of electric equipment.
At present, in low-voltage electrical apparatus field tests, the pressure regulator generally adopting load motor to drive and low-voltage high-current transformer form high constant-current source, as utility model patent CN105005344A discloses a kind of strong current generator, pressure regulator and low-voltage high-current transformer form the unitized construction of strong current generator, but because pressure regulator exists inertia, make Current adjustment inertia large, easily vibration is caused time near Current adjustment to setting value, thus can accuracy of detection be affected, although this patent is described in detail on hardware in addition, but in specifically how being realized by upper computer software controlling etc., do not make necessary explanation.And for example some documents propose a kind of take single-chip microcomputer as the constant current source control program of control core, because it lacks Current adjustment interface and interface intuitively, causes and integrates relative trouble with other test macros.
Summary of the invention
1, object of the present invention.
The present invention solves the necessary a current source of existing low-voltage electrical apparatus detection industry, this current source can meet wide region, high precision and friendly interface, easily and the specialized requirement such as test macro integration simultaneously, and proposes a kind of programmable current origin system based on LabVIEW.
2, the technical solution adopted in the present invention.
Programmable current origin system based on LabVIEW of the present invention, comprises regulator, protection and conversion equipment, control device:
Regulator comprises coarse adjustment pressure regulator, fine setting pressure regulator, fine setting transformer, ratio transformer and low-voltage high-current transformer: power frequency supply is connected by one end of contactor and coarse adjustment pressure regulator and the one end of finely tuning pressure regulator, the adjustable side of coarse adjustment pressure regulator is connected by the adjustable side of fine setting transformer with fine setting pressure regulator, the other end of fine setting transformer secondary coil is connected with one end of polytropic ratio tap transformer T1, three taps of polytropic ratio tap transformer T1 are connected respectively by contactor one end with low-voltage high-current transformer T2 primary coil, one end of low-voltage high-current transformer secondary coil connects wire, wire is through the current transformer in current measurement circuit, access product to be measured, the output voltage reference point of fine setting pressure regulator is at mid point, when finely tuning pressure regulator carbon brush position in neutral point position on the upper side, fine tuning transformer output voltage and coarse adjustment pressure regulator output voltage same-phase, the total output voltage of pressure regulator group is that both are added, otherwise then subtract each other, namely the voltage at the elementary two ends of polytropic ratio tap transformer T1 equals the algebraic sum of the voltage at coarse adjustment pressure regulator TD two ends and the voltage at fine tuning pressure regulator TDW level two ends, the voltage at fine tuning transformer BTDW level two ends is that the voltage at fine tuning pressure regulator TDW two ends obtains through fine tuning transformer BTDW conversion, namely indirectly can be changed the voltage at the elementary two ends of polytropic ratio tap transformer T1 by the value changing coarse adjustment pressure regulator and fine setting pressure regulator, and then carry out pressure regulation,
Described protection and conversion equipment comprise coarse and fine voltage regulation device spacing alarm protection module, median signal detection module: coarse and fine voltage regulation device spacing alarm module realizes primarily of travel switch, photoelectrical coupler and data collecting card; Travel switch provides spacing alarm for coarse adjustment pressure regulator, and travel switch is arranged on the bound position of thickness key depressor respectively, and the bound position signalling of coarse adjustment pressure regulator and fine setting pressure regulator sends into data collecting card through photoelectrical coupler; Current-voltage transformer in median signal detection module and sensor are with the current/voltage value on circuit in data collecting card combination metering system.
Control device mainly comprises host computer and data collecting card, the upper collection being gathered digital signal and simulating signal by calling data capture card, and is produced the pulse signal of certain frequency by the timing of capture card and tally function, the stepper motor in driving regulator.
Further in specific embodiment, coarse adjustment pressure regulator passes through driving stepper motor with fine setting pressure regulator, comprise stepper motor, stepper motor driver and travel switch XK1-XK4, the VCC of stepper motor driver of coarse adjustment pressure regulator and fine setting pressure regulator holds to hold to hold with the NC of travel switch XK1 with XK2 respectively with GND and is connected, coarse adjustment pressure regulator and A, B of the stepper motor driver of fine setting pressure regulator hold to hold with A, B of fine setting pressure regulator stepper motor with coarse adjustment pressure regulator respectively and are connected, and the DIR end of driver is connected with data collecting card respectively with CP end; Host computer calling data capture card produces the pulse signal of certain frequency, rotated by driver control stepper motor, the number of pulses of input determines that the angle that stepper motor turns over, the frequency of pulse determine the rotating speed of stepper motor, and then reaches control coarse adjustment pressure regulator and fine setting pressure regulator.
Further in specific embodiment; described travel switch has normally opened contact and normally closed contact; and there is a common port between the two; when implementing position limitation protection to pressure regulator; need by the electric power loop of the normally closed contact of microswitch access pressure regulator drive motor; disconnect drive motor power supply when pressure regulator is adjusted to extreme position need normally opened contact access data capture card again simultaneously, and the warning message by data collecting card pressure regulator being adjusted to extreme position passes to host computer.
A kind of programmable current source method, carry out in accordance with the following steps:
Step 1, reset operation
Coarse and fine voltage regulation device zero step, is transferred to lower limit by coarse adjustment pressure regulator; Fine tuning pressure regulator is adjusted to middle reference position, and it is zero that total voltage is exported, and the reset of coarse adjustment pressure regulator makes carbon brush get back to reference position, motor reversal is made by motor driver, when reference position got back to by carbon brush, trigger lower limit contact, motor stalls;
Fine tuning pressure regulator reset process: fine setting resets and adopts voltage sensor Real-time Collection fine setting pressure regulator contact and the potential difference (PD) at zero point, in whole test process, detect the position residing for adjustable side at any time according to current potential extent, more directly carry out back to zero from this position by control circuit regulating and controlling end;
Switch well until contactor each in circuit, start to regulate electric current according to current setting value;
Step 2, regulation voltage step, for stepper motor provides lasting pulse signal, drive motor rotates and carries out pressure regulation:
Step 2.1 judges that whether actual current is at coarse adjustment setting range
Gather the instantaneous value of electric current and finely tune other digital parameter in pressure regulator meta magnitude of voltage and read-write system, when actual current is outside coarse adjustment range, system enables coarse adjustment pressure regulator automatically, and now in coarse adjustment pressure regulator, stepper motor can select slewing rate and direction according to the difference of current actual value and setting value; When the actual value of electric current is less than coarse adjustment range, program will be stopped using coarse adjustment, jump to step 2.2, when judging that coarse adjustment pressure regulator carbon brush is positioned at upper limit or the lower limit of pressure regulator, jump to step 3 simultaneously;
Step 2.2 enables fine setting pressure regulator
Electric current is finely tuned, now finely tuning stepper motor in pressure regulator can select slewing rate and direction to stop finely tuning when the precision of electric current meets the precision required by system according to the difference of current actual value and setting value equally, Current adjustment terminates, by in system except power supply all switches, relay disconnect and quit a program, when judging in adjustment process that fine tuning pressure regulator carbon brush is positioned at upper limit or the lower limit of pressure regulator, jump to step 3;
Step 3 coarse and fine voltage regulation device spacing alarm step
While Current adjustment and reset operation; host computer adopts LabVIEW graphical programming language to write; position limitation protection is carried out to pressure regulator; spacing alarm switch can be triggered when coarse adjustment pressure regulator is positioned at upper limit or the lower limit of pressure regulator with the carbon brush of fine setting pressure regulator; host computer gathers alerting signal by data collecting card, stops the excessive adjustment behavior of pressure regulator at once.
Further in specific embodiment, described median signal detects and the collection of current-voltage transformer and sensor dynamic electrical parameter is realized by NIDAQmx calling data capture card.
Further in specific embodiment, voltage regulating mode in described pressure regulation step 2 provides lasting pulse signal for stepper motor, drive motor rotates, host computer is by the timer counter function of calling data capture card, one group of pulse signal continued can be produced, this shift pulse signal can be angular displacement by stepper motor, and the frequency of pulse signal and pulse number determine rotating speed and the stop position of stepper motor.
Further in specific embodiment, and automatic two kind control modes manual from main separation as required; During manual operation, motor uniform rotation, the frequency of the digit pulse that host computer produces is changeless, and this frequency presets; When enabling automatic operation, the rotating speed of stepper motor will change along with the change of Current adjustment precision, and host computer produces the digit pulse of changeable frequency, and this pulsed frequency is determined by host computer fuzzy controller; When performing automatic control program, manual adjustments program is by disabled, and when performing manual adjustments program, automatic control program is by disabled.
Further in specific embodiment, described fuzzy controller with the electric current collected for foundation, control rotating speed and the direction of stepper motor in pressure regulator, stepper motor is not uniform rotation, when application condition between setting value and instantaneous value is large, governing speed, the fuzzy controller in host computer produces high-frequency pulse signal and makes motor quick rotation, thus reaches the object of quick adjustment; Application condition hour between setting value and instantaneous value, degree of regulation, the fuzzy controller in host computer produces low-frequency pulse enable signal motor slow rotation, thus reaches the requirement of precision.
3, beneficial effect of the present invention.
(1) the present invention had both substantially increased the degree of regulation of electric current by the combination adopting coarse and fine voltage regulation device group and add transformer, had expanded again the scope of Current adjustment.
(2) upper computer software is by LabVIEW language compilation, is equipped with the collection that high-accuracy data collection card can realize electric current instantaneous value, controls pressure regulator and the actuating of relay, realize the object automatically regulating electric current.
(3) whole Current adjustment process adopts the mode of closed-loop control to realize, without the need to manual intervention.
(4) the present invention has abandoned the method in the past resetted, adopt voltage sensor Real-time Collection fine setting pressure regulator contact and the potential difference (PD) at zero point, back to zero is carried out according to current potential extent, instead of return meta tap position after first getting back to bound position, the reset operation of realization fine setting pressure regulator that so just can be not only fast but also accurate.
(5) the present invention has good stability and higher precision, and Current adjustment precision is less than 0.5%, and regulating time is generally at about 4s, and the range of adjustment of electric current is 0.1A to 1500A, can meet the requirement of low voltage electrical apparatus industry test preferably.
To sum up, the present invention is for solving the necessary a current source of existing low-voltage electrical apparatus detection industry, and this current source can meet wide region, high precision and friendly interface, easily and the specialized requirement such as test macro integration simultaneously.
Accompanying drawing explanation
Fig. 1 is overall construction drawing of the present invention.
Fig. 2 is main hardware structure figure of the present invention.
Fig. 3 is upper computer software program flow diagram of the present invention.
Fig. 4 is E(precision) membership function.
Fig. 5 is U(frequency dependence amount) membership function.
Fig. 6 is fuzzy control rule table.
Fig. 7 is Current adjustment interface.
Embodiment
In order to enable the auditor of Patent Office especially the public clearly understand technical spirit of the present invention and beneficial effect, applicant will elaborate below by way of example, but be not all the restriction to the present invention program to the description of embodiment, any conceive according to the present invention done be only pro forma but not substantial equivalent transformation and all should be considered as technical scheme category of the present invention.
Embodiment
Programmable current source based on LabVIEW of the present invention, the three-phase alternating current of high-precision large-range can be exported and dynamic current to export update time fast, can rapid succession change within the scope of gamut, and have manually and automatic two kinds of operator schemes, operation interface is short and sweet.
The present invention mainly comprises following three large modules: regulator, protection and conversion equipment and control device.
Upper computer software adopts the data stream mode combined with sequential organization of programme to realize, and the first frame branches into initialization primary module front panel, and initialization system startup primary module front panel shows the initial value of control and input control; Second frame branches into switch control rule, current/voltage gear is selected to control and coarse and fine voltage regulation device rezero operation; 3rd frame branches into electric parameter read-write, current regulation control and motor driver, wherein the read-write of electric parameter comprises the reading of dynamic mode analog quantity and the read-write of digital quantity, the read-write of described current regulation control, electric parameter and motor driver adopt parallel mode to run, and are independent of each other; 4th frame branches into reset routine, disconnects all switches and relay.Program adopts modularization programming thought to realize specific function.
The core of regulator is coarse adjustment pressure regulator, fine setting pressure regulator, fine setting transformer, polytropic ratio tap transformer and low-voltage high-current transformer.The voltage at the elementary two ends of polytropic ratio tap transformer T1 equals the algebraic sum of the voltage at coarse adjustment pressure regulator TD two ends and the voltage at fine tuning pressure regulator TDW level two ends.And the voltage that the voltage at fine tuning transformer BTDW level two ends is fine tuning pressure regulator TDW two ends obtains through fine tuning transformer BTDW conversion, namely indirectly can be changed the voltage at the elementary two ends of polytropic ratio tap transformer T1 by the value changing coarse adjustment pressure regulator and fine setting pressure regulator, and then reach the object of pressure regulation.Owing to finely tuning the output voltage reference point of pressure regulator at mid point, when finely tuning pressure regulator carbon brush position in neutral point position on the upper side, fine tuning transformer output voltage and coarse adjustment pressure regulator output voltage same-phase, the total output voltage of pressure regulator group is that both are added, otherwise then subtracts each other.Thus can regulate around current setting value when ensure that and adopt fine setting pressure regulator to carry out minute adjustment to electric current, reach and put forward high-precision object.
Described protection and conversion equipment are protected primarily of coarse and fine voltage regulation device spacing alarm, median signal detects and current-voltage transformer and sensor form.
While Current adjustment and reset operation; host computer can carry out position limitation protection to pressure regulator; spacing alarm switch can be triggered when coarse adjustment pressure regulator is positioned at upper limit or the lower limit of pressure regulator with the carbon brush of fine setting pressure regulator; host computer gathers alerting signal by data collecting card; the excessive adjustment behavior of pressure regulator can be stopped at once, avoid device damage.Described coarse and fine voltage regulation device spacing alarm protection is realized jointly by hardware circuit and software.Hardware adopts middle-size and small-size microswitch to carry out position limitation protection; this microswitch has normally opened contact and normally closed contact; and there is a common port between the two; when implementing position limitation protection to pressure regulator; need by the electric power loop of the normally closed contact of microswitch access pressure regulator drive motor; disconnect drive motor power supply when pressure regulator is adjusted to extreme position need normally opened contact access data capture card again simultaneously, and the warning message by data collecting card pressure regulator being adjusted to extreme position passes to host computer.Software section is used for the closure signal of normally opened contact in acquisition system, realizes the reading of spacing alarm signal, and concrete function is that the data acquisition program write by NIDAQmx is realized.First create tunnel (VI) by DAQmx, create single or multiple tunnel, and be added into task.Secondly starting task (VI) by DAQmx makes task be in running status, starts to measure or generate.The sampling in user's appointed task or tunnel is again read by DAQmx reading (VI).Remove task (VI) finally by DAQmx remove and exit this task.Wherein DAQmx reading VI will be placed in while circulation and constantly gather alerting signal; and make it to realize parallel running with coarse and fine voltage regulation device zero module, current regulation control device by local variable; start simultaneously; terminate, in pressure regulator, stepper motor provides protection for it while rotating simultaneously.
Described median signal detects and the collection of current-voltage transformer and sensor dynamic electrical parameter realizes mainly through NIDAQmx calling data capture card.Data Bian collection technology is a core technology of LabVIEW, is also the large advantage of LabVIEW compared with other compiler language.On the one hand the DAQmx technology of LabVIEW has oneself independently buffer memory, thus can not obliterated data when ensureing that continuous data gathers; DAQmx technology has direct memory access function on the other hand, thus can realize high-speed data and handle up.Concrete steps are as follows: first create tunnel VI by DAQmx and create single or multiple tunnel, arrange acquisition parameter, again sample mode and sampling rate are set by DAQmx timing VI, then starting task VI by DAQmx makes this task be in running status, and read the numerical value in VI reading user's appointed task or tunnel by DAQmx, this numerical value calculates the root-mean-square value of electric current by basic mean direct-root mean square VI, and the product of this root-mean-square value and current transformer coefficient is presented on front panel as the actual value of electric current.It should be noted that DAQmx reads VI and basic mean direct-root mean square VI and needs to be placed on the numerical value that constantly could read this passage in while circulation, current actual value on real-time update front panel, can remove task VI by DAQmx when finally circulation stops stop and remove this task, the acquisition tasks of dynamic electrical parameter completes.
Described control device mainly comprises pc control procedure and data collecting card.Host computer adopts LabVIEW graphical programming language to write.Control program mainly with the electric current collected for foundation, control rotating speed and the direction of stepper motor in pressure regulator.Stepper motor is not uniform rotation, in order to reach the not only fast but also accurate object of Current adjustment, when requiring that the application condition between setting value and instantaneous value is large, the speed regulated is principal contradiction, so require that host computer produces high-frequency pulse signal and makes motor quick rotation, thus reach the object of quick adjustment; Application condition hour between setting value and instantaneous value, the precision of adjustment is principal contradiction, so require that host computer produces low-frequency pulse enable signal motor slow rotation, thus reaches the requirement of precision.According to the requirement of system, this patent devises a fuzzy controller based on LabVIEW, well solves the contradiction between governing speed and precision.Fuzzy controller with error and error rate for input, output is an amount relevant to electric machine frequency, linked together by fuzzy control rule table between input and output amount, and choosing of fuzzy inference rule is for foundation with the size of error and error rate.The fuzzy logic control tool box (FuzzyLogicofToolkit) of LabVIEW, for the fuzzy controller of design basis rule, is mainly used in industrial stokehold and expert system.In the menu Tools of LabVIEW, select the FuzzySystemDesigner item in ControlDesign & Simulation, in the dialog box ejected, add input and output and determine membership function and fuzzy rule.
Described driving stepper motor module is mainly the pulse signal that stepper motor provides lasting, and drive motor rotates.Host computer is by the timer counter function of calling data capture card, and can produce one group of pulse signal continued, this shift pulse signal can be angular displacement by stepper motor, and the frequency of pulse signal and pulse number determine rotating speed and the stop position of stepper motor.Concrete steps are as follows: first call DAQmx and create tunnel VI function, this VI is polymorphic VI, and function selects CO pulsed frequency to produce herein, creates passage, arrange the parameter such as digital pulse frequency and dutycycle by this VI, generates digit pulse.Secondly every channel sample number and sampling pattern being set by calling DAQmx timing VI, then starting task VI by DAQmx and making task be in running status, starting to generate digit pulse.In while circulation, call DAQmx task subsequently and complete VI, make program continue to perform, produce continuous print pulse signal.Finally stop while circulation when Current adjustment completes or resetted, remove task VI by DAQmx and stop and know this task, stop pulse is produced.
Described current source system can need adopt manual adjustments or automatically regulate two kinds of regulative modes according to user.During manual operation, require motor uniform rotation, the frequency of the digit pulse of therefore host computer generation is changeless, and this frequency is artificially set by experiment by programmer.When enabling automatic operation, require that the rotating speed of stepper motor will change along with the change of Current adjustment precision, therefore host computer will produce the digit pulse of changeable frequency.This pulsed frequency is determined by host computer fuzzy controller.Manual adjustments and automatic adjustment are placed in the Liang Ge branch of case statement respectively, and synchronization only has a program to be performed.Namely when performing automatic control program, manual adjustments program is by disabled, and vice versa.Manual adjustments is to the expansion on automatic regulation function, makes the hommization more in application of this system.
Exactly coarse adjustment pressure regulator is transferred to lower limit by described coarse and fine voltage regulation device zero module, fine setting pressure regulator is adjusted to middle reference position, total it is zero that the voltage made exports.Due to coarse adjustment pressure regulator and the difference of finely tuning each self-structure of pressure regulator, reset operation is also different.The reset of coarse adjustment pressure regulator makes carbon brush get back to reference position, generally makes motor reversal by motor driver, when reference position got back to by carbon brush, triggers lower limit contact, motor stalls.And for fine setting pressure regulator, because its output voltage is the potential difference (PD) between its carbon brush current location and middle reference position, therefore its reset carbon brush is adjusted to middle reference position, is namely its zero-bit.The mode of the employing time controling that fine setting reset operation is herein different from the past makes fine setting pressure regulator back to zero.Concrete operations first make the adjustable side of fine setting pressure regulator rotate forward to arrive upper limit or reversion arrival lower position, the adjustable side of estimation fine setting pressure regulator is adjusted to the time of meta tap position from upper limit or lower limit again, then according to the time estimated in advance, make that the adjustable side of fine setting pressure regulator is positive/negative to be turned the time and get back to meta tap position, the shortcoming of this mode is that back to zero accuracy is not high and the back to zero time is long, efficiency is poor.Patent of the present invention has abandoned the method in the past resetted, adopt voltage sensor Real-time Collection fine setting pressure regulator contact and the potential difference (PD) at zero point, in whole test process, the position residing for adjustable side just can be detected at any time according to current potential extent, directly back to zero is carried out from this position again by control circuit regulating and controlling end, instead of return meta tap position after first getting back to bound position, the reset operation of realization fine setting pressure regulator that so just can be not only fast but also accurate.
Described reseting module, exactly when Current adjustment completes, after terminating current test item, by all switches, relay disconnection except power supply in system, and will exit this program.Switch control rule is that host computer writes VI to data collecting card related port transmission digital signal by DAQmx, and control hardware circuit, realizes the reset of switch, relay.
Embodiment 2
The core of the programmable current origin system based on LabVIEW of the present invention is coarse and fine voltage regulation device group, polytropic ratio tap transformer, high precision electric current transducer and high precision pci data capture card, industrial computer, LabVIEW control program.As shown in Figure 1.The combination that system adopts coarse and fine voltage regulation device group to add transformer had both substantially increased the degree of regulation of electric current, had expanded again the scope of Current adjustment.Upper computer software by LabVIEW language compilation, is equipped with the collection that high-accuracy data collection card can realize electric current instantaneous value, controls pressure regulator and the actuating of relay, realize the object automatically regulating electric current.Whole Current adjustment process adopts the mode of closed-loop control to realize, without the need to manual intervention.
The core of hardware is coarse and fine voltage regulation device group, fine tuning transformer, polytropic ratio tap transformer.As shown in Figure 2, the voltage at the elementary two ends of polytropic ratio tap transformer T1 just equals the algebraic sum of the voltage at coarse adjustment pressure regulator TD two ends and the voltage at fine tuning transformer BTDW level two ends.And the voltage that the voltage at fine tuning transformer BTDW level two ends is fine setting pressure regulator TDW two ends obtains through fine tuning transformer BTDW conversion, namely indirectly can be changed the voltage at the elementary two ends of polytropic ratio tap transformer T1 by the value changing coarse and fine voltage regulation device, and then reach the object of pressure regulation.Owing to finely tuning the output voltage reference point of pressure regulator at mid point, when fine tuning pressure regulator carbon brush position is in neutral point position on the upper side, fine tuning transformer output voltage and coarse adjustment pressure regulator output voltage same-phase, the total output voltage of pressure regulator group is that both are added, otherwise then subtracts each other.Thus can regulate around current setting value when ensure that and adopt fine setting pressure regulator to carry out minute adjustment to electric current, reach and put forward high-precision object.Ratio transformer T1 for further expanding the scope of constant source flowing system output current, its output voltage is divided into 50,100, a 220V3 gear.According to the size of current required for the different current specification of test product and different test event, by the switching of LabVIEW automatic control relay and contactor, select the gear of required output voltage with this.For convenience of description, for A phase.Coarse adjustment pressure regulator TD is 2kVA, and output voltage is 0 ~ 250V, and fine setting pressure regulator TDW is 0.5kVA, and the reference point of output voltage is at pressure regulator central point, and the rated output voltage of its corresponding fine tuning transformer BTDW connected is 10V.
Current Control overall procedure as shown in Figure 3, for A phase in figure.Larger impact is produced when cutting for avoiding electric current, program run start time first reset operation, coarse adjustment pressure regulator is transferred to lower limit, fine tuning pressure regulator is adjusted to middle reference position, it is zero that total voltage is exported, switch well until contactor each in circuit, start to regulate electric current according to current setting value.When A phase actual current is outside coarse adjustment range, system enables coarse adjustment pressure regulator automatically, and now in coarse adjustment pressure regulator, stepper motor can select slewing rate and direction according to the difference of A phase current actual value and setting value.When the actual value of electric current is less than coarse adjustment range, inactive coarse adjustment is enabled fine setting pressure regulator by program, finely tunes electric current, now finely tunes stepper motor in pressure regulator and can select slewing rate and direction according to the difference of A phase current actual value and setting value equally.Stop fine setting when the precision of electric current meets the precision required by system, Current adjustment terminates.
Fig. 7 is the front panel of Current adjustment program, and for convenience of using, in the process of Current adjustment, front panel can show electric current or magnitude of voltage in real time, and alerting signal.The left side of Fig. 7 shows the parameters of three-phase current in adjustment process, as setting current value, actual current, Current adjustment precision and regulating time, makes test process very clear.The middle part of panel then illustrates Current adjustment mode and each phase alerting signal and Current adjustment direction (rise or decline), manual operation can be adopted as required to regulate or automatically regulate, in a manual mode, electric current rises and declines while adjustment button is pressed and can light, double lamp of giving instruction uses, to point out operator the direction that current pressure regulator is regulating.When pressure regulator runs to extreme position, corresponding upper and lower limit signal lamp is bright, notes to point out operator.The right side of panel is " test process prompting " frame and two buttons, " test process prompting " frame can be presented at the fault cues and operation indicating that may run in the process of test, click " entering next step " and then can carry out next step test, click " exiting " then can be exited and change program.Interface is simple and clear, is easy to operation.
Claims (8)
1. based on a programmable current origin system of LabVIEW, it is characterized in that: comprise regulator, protection and conversion equipment, control device:
Regulator comprises coarse adjustment pressure regulator, fine setting pressure regulator, fine setting transformer, ratio transformer and low-voltage high-current transformer: power frequency supply is connected by one end of contactor and coarse adjustment pressure regulator and the one end of finely tuning pressure regulator, the adjustable side of coarse adjustment pressure regulator is connected by the adjustable side of fine setting transformer with fine setting pressure regulator, the other end of fine setting transformer secondary coil is connected with one end of polytropic ratio tap transformer T1, three taps of polytropic ratio tap transformer T1 are connected respectively by contactor one end with low-voltage high-current transformer T2 primary coil, one end of low-voltage high-current transformer secondary coil connects wire, wire is through the current transformer in current measurement circuit, access product to be measured, the output voltage reference point of fine setting pressure regulator is at mid point, when finely tuning pressure regulator carbon brush position in neutral point position on the upper side, fine tuning transformer output voltage and coarse adjustment pressure regulator output voltage same-phase, the total output voltage of pressure regulator group is that both are added, otherwise then subtract each other, namely the voltage at the elementary two ends of polytropic ratio tap transformer T1 equals the algebraic sum of the voltage at coarse adjustment pressure regulator TD two ends and the voltage at fine tuning pressure regulator TDW level two ends, the voltage at fine tuning transformer BTDW level two ends is that the voltage at fine tuning pressure regulator TDW two ends obtains through fine tuning transformer BTDW conversion, namely indirectly can be changed the voltage at the elementary two ends of polytropic ratio tap transformer T1 by the value changing coarse adjustment pressure regulator and fine setting pressure regulator, and then carry out pressure regulation,
Described protection and conversion equipment comprise coarse and fine voltage regulation device spacing alarm protection module, median signal detection module: coarse and fine voltage regulation device spacing alarm module realizes primarily of travel switch, photoelectrical coupler and data collecting card; Travel switch provides spacing alarm for coarse adjustment pressure regulator, and travel switch is arranged on the bound position of thickness key depressor respectively, and the bound position signalling of coarse adjustment pressure regulator and fine setting pressure regulator sends into data collecting card through photoelectrical coupler; Current-voltage transformer in median signal detection module and sensor are with the current/voltage value on circuit in data collecting card combination metering system;
Control device mainly comprises host computer and data collecting card, the upper collection being gathered digital signal and simulating signal by calling data capture card, and is produced the pulse signal of certain frequency by the timing of capture card and tally function, the stepper motor in driving regulator.
2. the programmable current origin system based on LabVIEW according to claim 1, it is characterized in that: coarse adjustment pressure regulator passes through driving stepper motor with fine setting pressure regulator, comprise stepper motor, stepper motor driver and travel switch XK1-XK4, the VCC of stepper motor driver of coarse adjustment pressure regulator and fine setting pressure regulator holds to hold to hold with the NC of travel switch XK1 with XK2 respectively with GND and is connected, the A of the stepper motor driver of coarse adjustment pressure regulator and fine setting pressure regulator, B holds the A respectively with coarse adjustment pressure regulator and fine setting pressure regulator stepper motor, B end is connected, the DIR end of driver is connected with data collecting card respectively with CP end, host computer calling data capture card produces the pulse signal of certain frequency, rotated by driver control stepper motor, the number of pulses of input determines that the angle that stepper motor turns over, the frequency of pulse determine the rotating speed of stepper motor, and then reaches control coarse adjustment pressure regulator and fine setting pressure regulator.
3. the programmable current origin system based on LabVIEW according to claim 1; it is characterized in that: described travel switch has normally opened contact and normally closed contact; and there is a common port between the two; when implementing position limitation protection to pressure regulator; need by the electric power loop of the normally closed contact of microswitch access pressure regulator drive motor; disconnect drive motor power supply when pressure regulator is adjusted to extreme position need normally opened contact access data capture card again simultaneously, and the warning message by data collecting card pressure regulator being adjusted to extreme position passes to host computer.
4. a programmable current source method for the system as described in claim 1-3, is characterized in that carrying out in accordance with the following steps:
Step 1, reset operation
Coarse and fine voltage regulation device zero step, is transferred to lower limit by coarse adjustment pressure regulator; Fine tuning pressure regulator is adjusted to middle reference position, and it is zero that total voltage is exported, and the reset of coarse adjustment pressure regulator makes carbon brush get back to reference position, motor reversal is made by motor driver, when reference position got back to by carbon brush, trigger lower limit contact, motor stalls;
Fine tuning pressure regulator reset process: fine setting resets and adopts voltage sensor Real-time Collection fine setting pressure regulator contact and the potential difference (PD) at zero point, in whole test process, detect the position residing for adjustable side at any time according to current potential extent, more directly carry out back to zero from this position by control circuit regulating and controlling end;
Switch well until contactor each in circuit, start to regulate electric current according to current setting value;
Step 2, regulation voltage step, for stepper motor provides lasting pulse signal, drive motor rotates and carries out pressure regulation:
Step 2.1 judges that whether actual current is at coarse adjustment setting range
Gather the instantaneous value of electric current and finely tune other digital parameter in pressure regulator meta magnitude of voltage and read-write system, when actual current is outside coarse adjustment range, system enables coarse adjustment pressure regulator automatically, and now in coarse adjustment pressure regulator, stepper motor can select slewing rate and direction according to the difference of current actual value and setting value; When the actual value of electric current is less than coarse adjustment range, program will be stopped using coarse adjustment, jump to step 2.2, when judging that coarse adjustment pressure regulator carbon brush is positioned at upper limit or the lower limit of pressure regulator, jump to step 3 simultaneously;
Step 2.2 enables fine setting pressure regulator
Electric current is finely tuned, now finely tuning stepper motor in pressure regulator can select slewing rate and direction to stop finely tuning when the precision of electric current meets the precision required by system according to the difference of current actual value and setting value equally, Current adjustment terminates, by in system except power supply all switches, relay disconnect and quit a program, when judging in adjustment process that fine tuning pressure regulator carbon brush is positioned at upper limit or the lower limit of pressure regulator, jump to step 3;
Step 3 coarse and fine voltage regulation device spacing alarm step
While Current adjustment and reset operation; host computer adopts LabVIEW graphical programming language to write; position limitation protection is carried out to pressure regulator; spacing alarm switch can be triggered when coarse adjustment pressure regulator is positioned at upper limit or the lower limit of pressure regulator with the carbon brush of fine setting pressure regulator; host computer gathers alerting signal by data collecting card, stops the excessive adjustment behavior of pressure regulator at once.
5. the programmable current source method based on LabVIEW according to claim 4, is characterized in that: described median signal detects and the collection of current-voltage transformer and sensor dynamic electrical parameter is realized by NIDAQmx calling data capture card.
6. the programmable current source method based on LabVIEW according to claim 4, it is characterized in that: the voltage regulating mode in described pressure regulation step 2 provides lasting pulse signal for stepper motor, drive motor rotates, host computer is by the timer counter function of calling data capture card, one group of pulse signal continued can be produced, this shift pulse signal can be angular displacement by stepper motor, and the frequency of pulse signal and pulse number determine rotating speed and the stop position of stepper motor.
7. the programmable current source method based on LabVIEW according to claim 4, is characterized in that: and automatic two kind control modes manual from main separation as required; During manual operation, motor uniform rotation, the frequency of the digit pulse that host computer produces is changeless, and this frequency presets; When enabling automatic operation, the rotating speed of stepper motor will change along with the change of Current adjustment precision, and host computer produces the digit pulse of changeable frequency, and this pulsed frequency is determined by host computer fuzzy controller; When performing automatic control program, manual adjustments program is by disabled, and when performing manual adjustments program, automatic control program is by disabled.
8. the programmable current source method based on LabVIEW according to claim 7, it is characterized in that: described fuzzy controller with the electric current collected for foundation, control rotating speed and the direction of stepper motor in pressure regulator, stepper motor is not uniform rotation, when application condition between setting value and instantaneous value is large, governing speed, the fuzzy controller in host computer produces high-frequency pulse signal and makes motor quick rotation, thus reaches the object of quick adjustment; Application condition hour between setting value and instantaneous value, degree of regulation, the fuzzy controller in host computer produces low-frequency pulse enable signal motor slow rotation, thus reaches the requirement of precision.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201511016024.7A CN105424993A (en) | 2015-12-30 | 2015-12-30 | LabVIEW-based programmable current source system and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201511016024.7A CN105424993A (en) | 2015-12-30 | 2015-12-30 | LabVIEW-based programmable current source system and method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN105424993A true CN105424993A (en) | 2016-03-23 |
Family
ID=55503326
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201511016024.7A Pending CN105424993A (en) | 2015-12-30 | 2015-12-30 | LabVIEW-based programmable current source system and method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105424993A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107515322A (en) * | 2017-10-25 | 2017-12-26 | 国网四川省电力公司电力科学研究院 | A kind of experiment power supply suitable for trichotomy Site Detection power distribution network transformer error |
| CN108832820A (en) * | 2018-03-08 | 2018-11-16 | 国网上海市电力公司 | A kind of program-controlled high-voltage great-current regulator |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201796057U (en) * | 2010-08-12 | 2011-04-13 | 常熟理工学院 | Current generation device based on virtual instrument technology |
| US20130057251A1 (en) * | 2010-03-31 | 2013-03-07 | Jin Hong Ahn | Reference potential adjustment device and a measuring device equipped with the same |
| CN103279159A (en) * | 2013-05-13 | 2013-09-04 | 常熟理工学院 | Stepping current source device based on virtual instrument technology |
| CN103278668A (en) * | 2013-05-13 | 2013-09-04 | 常熟理工学院 | Stepping current source |
| CN203259552U (en) * | 2013-05-13 | 2013-10-30 | 常熟理工学院 | Virtual instrument technology-based stepping current source apparatus |
| CN203337696U (en) * | 2013-05-13 | 2013-12-11 | 常熟理工学院 | Stepping current source |
| CN104535808A (en) * | 2015-01-05 | 2015-04-22 | 北京天源科创风电技术有限责任公司 | Adjustable voltage source test platform |
| CN205374536U (en) * | 2015-12-30 | 2016-07-06 | 常熟理工学院 | Programme -controlled electric current source system based on labVIEW |
-
2015
- 2015-12-30 CN CN201511016024.7A patent/CN105424993A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130057251A1 (en) * | 2010-03-31 | 2013-03-07 | Jin Hong Ahn | Reference potential adjustment device and a measuring device equipped with the same |
| CN201796057U (en) * | 2010-08-12 | 2011-04-13 | 常熟理工学院 | Current generation device based on virtual instrument technology |
| CN103279159A (en) * | 2013-05-13 | 2013-09-04 | 常熟理工学院 | Stepping current source device based on virtual instrument technology |
| CN103278668A (en) * | 2013-05-13 | 2013-09-04 | 常熟理工学院 | Stepping current source |
| CN203259552U (en) * | 2013-05-13 | 2013-10-30 | 常熟理工学院 | Virtual instrument technology-based stepping current source apparatus |
| CN203337696U (en) * | 2013-05-13 | 2013-12-11 | 常熟理工学院 | Stepping current source |
| CN104535808A (en) * | 2015-01-05 | 2015-04-22 | 北京天源科创风电技术有限责任公司 | Adjustable voltage source test platform |
| CN205374536U (en) * | 2015-12-30 | 2016-07-06 | 常熟理工学院 | Programme -controlled electric current source system based on labVIEW |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107515322A (en) * | 2017-10-25 | 2017-12-26 | 国网四川省电力公司电力科学研究院 | A kind of experiment power supply suitable for trichotomy Site Detection power distribution network transformer error |
| CN108832820A (en) * | 2018-03-08 | 2018-11-16 | 国网上海市电力公司 | A kind of program-controlled high-voltage great-current regulator |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103248294B (en) | Position-sensor-free DC brushless motor double closed loop speed regulation system control method | |
| CN103672995B (en) | The air quantity autocontrol method of range hood and range hood | |
| CN100462729C (en) | On-line monitoring method for winding turn-to-turn short-circuit of distribution generator stator based on multi-criterion mixing | |
| CN104215930B (en) | A kind of three-in-one acquisition terminal detection device | |
| CN101895085B (en) | Power supply circuit protective device and protective control method | |
| CN102722107A (en) | Intelligent integrated development and test system for high-voltage frequency converter and establishment method thereof | |
| CN205901649U (en) | Step motor control driver based on singlechip | |
| CN103199514A (en) | Method of eliminating ferromagnetic resonances | |
| CN103116128A (en) | Breaker overload testing device and operation method thereof | |
| CN103728949A (en) | Integrated control device of hydroelectric generating set | |
| CN202285026U (en) | Voltage sag generator | |
| CN105424993A (en) | LabVIEW-based programmable current source system and method | |
| CN205374536U (en) | Programme -controlled electric current source system based on labVIEW | |
| CN108646066A (en) | DC test instrument programmable state sequence dynamic generating system | |
| CN105785169A (en) | Battery system pre-charging management testing device and testing method thereof | |
| CN211042425U (en) | Intelligent diaphragm type gas meter main control board function detection device | |
| CN106353592A (en) | Test system based on simulated intelligent electric energy meter | |
| CN101640425A (en) | Intelligent electric load management device | |
| CN201478839U (en) | Intelligent type power load management apparatus | |
| CN102890256B (en) | Failure current simulator and working method thereof | |
| CN101950009A (en) | Three-phase intelligent transformer calibrator | |
| CN107798945A (en) | A kind of teaching method based on graphical digital programmable relay protection experimental | |
| CN211402564U (en) | Automatic testing arrangement of new energy automobile battery charging outfit | |
| CN102721878A (en) | Intelligentized automatic checkout device of quartz crystal oscillator instrument | |
| CN103580654B (en) | Reactor period signal generator and its implementation and using method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20160323 |
|
| RJ01 | Rejection of invention patent application after publication |