CN205720627U - Numeral partial pressure type mutual inductor tester whole body assay device - Google Patents
Numeral partial pressure type mutual inductor tester whole body assay device Download PDFInfo
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- CN205720627U CN205720627U CN201620305227.1U CN201620305227U CN205720627U CN 205720627 U CN205720627 U CN 205720627U CN 201620305227 U CN201620305227 U CN 201620305227U CN 205720627 U CN205720627 U CN 205720627U
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Abstract
This utility model relates to numeral partial pressure type mutual inductor tester whole body assay device, and microprocessor is connected with numerical control power frequency component generator, and the signal after microprocessor will be automatically adjusted sends generator one power frequency component of generation to；Generator and the first amplifier connect, and the first amplifier is connected with current lifting device and booster respectively；Current lifting device is connected with sampled current transformer；Booster is connected with sampling voltage transformer；Sampled current transformer and sampling voltage transformer are connected with signal synthesis circuit respectively, and signal synthesis circuit and the second amplifier connect；Microprocessor is connected with the second amplifier, signal synthesis circuit and touch display screen respectively.This utility model uses the FPGA DDS technology of high stability to produce stable frequency standard, it is used for examining and determine the science detecting instrument of the power frequency vector small-signal detection of similar error of measurement formula principle, may also be used for examining and determine impedance, the small area analysis vectors such as admittance, small voltage vector and their high accuracy decomposition amount.
Description
Technical field
This utility model belongs to the science detecting instrument of power frequency vector small-signal detection, is specifically related to a kind of numeral partial pressure type mutual
Sensor tester Integral calibrating apparatus.
Background technology
Numeral partial pressure type mutual inductor tester whole body assay device uses the principles of electric and electronic engineering to be made up of passive device at present.Its circuit
Complicated heavy, amount limit is narrow, and automaticity is low.Its reason has: 1 decimal scale being made up of electromagnetic transformer cascade is divided
Depressor, in-phase component needs level Four, quadrature component to need level Four.Every grade will ten Controls.Add various
Function and reversing switch, the quantity of relay nearly hundred.(the most charged switching of these relays)；2 quadrature components
Being produced by passive element capacitor phase shift, need the electric capacity of significant volume, load capacity residual quantity limit is narrow.
Along with the progress of electronic technology, quick current switch and laser trimming film resistor network composition, in high precision,
High linearity, high resolution, the integrated circuit electronic potentiometer of pole Low Drift Temperature.At power frequency vector small signal process field ratio
Electromagnetic transformer performance is more superior, can realize Digital Control, and expand its range of application.
Summary of the invention
The purpose of this utility model is to provide a kind of numeral partial pressure type mutual inductor tester whole body assay device.This practicality is new
Type uses the FPGA-DDS technology of high stability to produce stable frequency standard, is used for examining and determine the mutual of similar error of measurement formula principle
The science of the detections of power frequency vector small-signal such as sensor tester, mutual inductor load box tester, secondary voltage drop load tester
Detecting instrument, it is also possible to be used for examining and determine the small area analysis vectors such as impedance, admittance, small voltage vector and their high accuracy and divide
Xie Liang.
The technical solution adopted in the utility model:
Numeral partial pressure type mutual inductor tester whole body assay device, it includes generator, the first amplifier, current lifting device, takes
Sample current transformer, booster, sampling voltage transformer, signal synthesis circuit, the second amplifier, microprocessor and touch
Touching display screen, wherein, microprocessor is connected with numerical control power frequency component generator, microprocessor will be automatically adjusted after signal
Send generator to and produce a power frequency component；
Generator and the first amplifier connect, and generator sends described power frequency component to first amplifier, amplify first
Producing a predeterminated voltage signal in device, the first amplifier is connected with current lifting device and booster respectively, and the first amplifier is by institute
State predeterminated voltage signal and send current lifting device and booster to；
Current lifting device is connected with sampled current transformer, and the predeterminated voltage signal liter that the first amplifier is sent here by current lifting device becomes one
Current signal, and exported by outfan To and Tx on current lifting device, described current signal is become by sampled current transformer
Sampled signal is become to deliver to signal synthesis circuit；
Booster is connected with sampling voltage transformer, and the predeterminated voltage signal that the first amplifier is sent here by booster generates one
Voltage signal, and exported by outfan a and x on booster, described voltage signal is become by sampling voltage transformer
Sampled signal delivers to signal synthesis circuit；
Sampled current transformer and sampling voltage transformer are connected with signal synthesis circuit respectively, signal synthesis circuit and second
Amplifier connects, and the sampled signal that sampled current transformer or sampling voltage transformer are sent here is just being carried out by signal synthesis circuit
Hand over phase shift 90 degree, the most orthogonal dividing potential drop；Synchronous signal combiner circuit is by sampled current transformer or sampling voltage transformer
The sampled signal sent here carries out homophase dividing potential drop, finally homophase dividing potential drop and orthogonal voltage division signal is carried out signal syntheses, and passes through
Outfan K and the D output of the second amplifier；
Microprocessor is connected with the second amplifier, signal synthesis circuit and touch display screen respectively, by touching display screen
Upper manipulation microprocessor sends instruction to generator, the second amplifier, signal synthesis circuit, it is achieved output signal from
Dynamic regulation.
Further, also include one measure feedback circuit, described measurement feedback circuit by the 3rd amplifier, wave filter,
AD637 transducer and A/D converter composition, the 3rd amplifier and sampled current transformer and sampling voltage transformer defeated
Go out end connect, the 3rd amplifier is connected with wave filter, and wave filter is connected with AD637 transducer, AD637 transducer and
A/D converter connects, and A/D converter is connected with microprocessor；Measure feedback circuit by sampled signal Real-time Feedback to micro-
Processor, it is ensured that be output as constant current constant voltage signal.
Further, described signal synthesis circuit is by follower, the first phase inverter, the second phase inverter, the phase shifter, anti-
Phase and amplitude device, the first potentiometer, the second potentiometer, the first relay, the second relay and adder；Follower is respectively
It is connected with the first phase inverter and the second phase inverter；Sampled signal drives through follower and delivers to the first phase inverter and second anti-respectively
Phase device；
First phase inverter is connected with two the first potentiometer respectively by the first relay, and sampled signal produces through the first phase inverter
Raw in-phase component-f and in-phase component+f, in-phase component-f receive the normally opened end of the first relay, and in-phase component+f receives the
The normal-closed end of one relay, in-phase component ± f is selected to deliver to the Voltage Reference of two the first potentiometer respectively by the first relay
Benchmark Vref end；
Second phase inverter is connected with phase shifter and anti-phase amplitude modulator successively by the second relay, and anti-phase amplitude modulator is respectively with two
Individual second potentiometer connects, and sampled signal produces-& quadrature component and+& quadrature component ,-& quadrature component through the second phase inverter
Receiving the normally opened end of the second relay ,+& quadrature component receives the normal-closed end of the second relay, and ± & quadrature component is by relay
Device selects to deliver to phase shifter phase shift 90 degree and produces quadrature component, and the most inverted amplitude modulator of quadrature component carries out anti-phase and amplitude tune
Whole, it is then sent through the voltage reference Vref end of two the second potentiometer；
First potentiometer and the second potentiometer are all connected with microprocessor, and the first potentiometer and the second potentiometer are all and adder
Connecting, described in-phase component ± f is closed by adder after the second potentiometer through the first potentiometer, ± & quadrature component
Become to deliver to the second amplifier to amplify.
Further, the first described potentiometer and the second potentiometer by AD7545D/A transducer, operational amplifier,
Data latches and address decoder composition, address decoder connects with data latches and AD7545D/A transducer respectively
Connecing, data latches is connected with AD7545D/A transducer, and AD7545D/A transducer is connected with operational amplifier, micro-
Processor is connected with data latches, address decoder and AD7545D/A transducer respectively, and in-phase component ± f connects two
Individual first potentiometer, ± & quadrature component connect two the second potentiometer can improve the resolution of dividing potential drop, and AD7545D/A turns
In-phase component ± f and ± & quadrature component are decomposed into D*Vref/2 by parallel operation under control of the microprocessor24, wherein D be 0～
224。
Described generator is numerical control power frequency component generator, and it uses amplifier employing to have stream, overheated, overvoltage guarantor
The OPA integrated amplifier composition protected.
Compared with prior art it provides the benefit that this utility model: (1) test power frequency source signal precision high stability is good,
MCU controls to realize several working ways by RS232 mouth；(2) use digital four-quadrant multiplier to homophase and just
Handing over component to carry out 1/16777215 dividing potential drop, resolution is high, good stability, can change under any duty homophase with
The value of quadrature component；(3) use nA level electronic component realize signal anti-phase, synthesize, drive, it is ensured that output signal exists
μ A level is reliable and stable, and has the good error of zero and heat stability；(4) this utility model use by amplifier,
The measurement feedback circuit that wave filter, AD637 and A/D converter are formed, it is ensured that sampled signal Real-time Feedback is to micro-process
Device, the given link sending instruction to FPGA with touch screen operation constitutes closed loop control, it is ensured that output constant current constant voltage, and
And it is shown in touch display screen.
Accompanying drawing explanation
Fig. 1 is general frame connection diagram of the present utility model；
Fig. 2 is the framework connection diagram of signal synthesis circuit in Fig. 1.
Detailed description of the invention
As it is shown in figure 1, numeral partial pressure type mutual inductor tester whole body assay device, it includes that generator 1, first amplifies
Device 2, current lifting device 3, sampled current transformer 4, booster 5, sampling voltage transformer 6, signal synthesis circuit 7,
Two amplifiers 8, microprocessor 9 and touch display screen 10, wherein, microprocessor 9 is connected with generator 1, micro-process
Signal after device 9 will be automatically adjusted sends generator 1 to and produces a power frequency component；Described generator 1 uses numerical control power frequency
Signal generator.
Generator 1 is connected with the first amplifier 2, and described power frequency component is sent to the first amplifier 2 by generator 1,
Producing a predeterminated voltage signal in first amplifier 2, the first amplifier 2 is connected with current lifting device 3 and booster 5 respectively,
First amplifier 2 sends described predeterminated voltage signal to current lifting device 3 and booster 5；
Current lifting device 3 is connected with sampled current transformer 4, the predeterminated voltage signal that the first amplifier 2 is sent here by current lifting device 3
Generating a current signal, and exported by outfan To and Tx on current lifting device 3, sampled current transformer 4 is by described
Current signal becomes sampled signal and delivers to signal synthesis circuit 7；
Booster 5 is connected with sampling voltage transformer 6, the predeterminated voltage signal that the first amplifier 2 is sent here by booster 5
Generating a voltage signal, and exported by outfan a and x on booster 5, sampling voltage transformer 6 is by described electricity
Pressure signal becomes sampled signal and delivers to signal synthesis circuit 7；
Sampled current transformer 4 and sampling voltage transformer 6 are connected with signal synthesis circuit 7 respectively, signal synthesis circuit
7 are connected with the second amplifier 8, and sampled current transformer 4 or sampling voltage transformer 6 are sent here by signal synthesis circuit 7
Sampled signal carries out orthogonal phase shift 90 degree, the most orthogonal dividing potential drop；Synchronous signal combiner circuit 7 is by sampled current transformer
4 or the sampled signal sent here of sampling voltage transformer 6 carry out homophase dividing potential drop, finally homophase dividing potential drop and orthogonal voltage division signal are entered
Row signal syntheses, and exported by outfan K and D of the second amplifier 8；
Microprocessor 9 is connected with the second amplifier 8, signal synthesis circuit 7 and touch display screen 10 respectively, by touching
Touch manipulation microprocessor 9 on display screen 10 and generator the 1, second amplifier 8, signal synthesis circuit 7 sent instruction,
Realize being automatically adjusted of output signal.
This utility model also includes that is measured a feedback circuit, and described measurement feedback circuit is by the 3rd amplifier 11, wave filter
12, AD637 transducer 13 and A/D converter 14 form, the 3rd amplifier 11 and sampled current transformer 4 and take
The outfan of sample voltage transformer 6 connects, and the 3rd amplifier 11 is connected with wave filter 12, wave filter 12 and AD637
Transducer 13 connects, and AD637 transducer 13 is connected with A/D converter 14, A/D converter 14 and microprocessor 9
Connect；Measure feedback circuit by sampled signal Real-time Feedback to microprocessor 9, it is ensured that be output as constant current constant voltage signal.
Such as Fig. 2, described signal synthesis circuit 7 is by follower the 15, first phase inverter the 16, second phase inverter 17, shifting
Phase device 18, anti-phase amplitude modulator the 19, first potentiometer the 20, second potentiometer the 21, first relay the 22, second relay
23 and adder 24；Follower 15 is connected with the first phase inverter 16 and the second phase inverter 17 respectively；Sampled signal through with
Drive with device 15 and deliver to the first phase inverter 16 and the second phase inverter 17 respectively；
First phase inverter 16 is connected with two the first potentiometer 20 respectively by the first relay 22, and sampled signal is through the
One phase inverter 16 produces in-phase component-f and in-phase component+f, and in-phase component-f receives the normally opened end of the first relay 22, with
Phase component+f receives the normal-closed end of the first relay 22, and in-phase component ± f is selected by the first relay 22 to deliver to two respectively
The voltage reference Vref end of the first potentiometer 20；
Second phase inverter 17 is connected with phase shifter 18 and anti-phase amplitude modulator 19 successively by the second relay 23, anti-phase tune
Width device 19 is connected with two the second potentiometer 21 respectively, and sampled signal produces-& quadrature component and+& through the second phase inverter 17
Quadrature component ,-& quadrature component receives the normally opened end of the second relay 23, and+& quadrature component receives the second relay 23
Normal-closed end, ± & quadrature component is selected to deliver to 90 degree of generation quadrature components of phase shifter 18 phase shift, quadrature component by relay
The most inverted amplitude modulator 19 carries out anti-phase and range-adjusting, is then sent through the voltage reference Vref of two the second potentiometer 21
End；
First potentiometer 20 and the second potentiometer 21 are all connected with microprocessor 9, the first potentiometer 20 and the second dividing potential drop
Device 21 is all connected with adder 24, described in-phase component ± f through the first potentiometer 20, ± & quadrature component through second
Deliver to the second amplifier 8 by adder 24 synthesis after potentiometer 21 amplify.
The first described potentiometer 20 and the second potentiometer 21 by AD7545D/A transducer 25, operational amplifier 26,
Data latches 27 and address decoder 28 form, address decoder 28 respectively with data latches 27 and AD7545D/A
Transducer 25 connects, and data latches 27 is connected with AD7545D/A transducer 25, AD7545D/A transducer 25
Be connected with operational amplifier 26, microprocessor 9 respectively with data latches 27, address decoder 28 and AD7545D/A
Transducer 25 connects, and in-phase component ± f connects two the first potentiometer 20, ± & quadrature component connects two the second dividing potential drops
Device 21 can improve the resolution of dividing potential drop, AD7545D/A transducer 25 under control of a microprocessor 9 by in-phase component ±
F and ± & quadrature component are decomposed into D*Vref/224, wherein D is 0～224。
Claims (5)
1. numeral partial pressure type mutual inductor tester whole body assay device, it is characterised in that it includes generator, the first amplification
Device, current lifting device, sampled current transformer, booster, sampling voltage transformer, signal synthesis circuit, the second amplifier,
Microprocessor and touch display screen, wherein, microprocessor is connected with numerical control power frequency component generator, and microprocessor will be automatically
Signal after regulation sends generator to and produces a power frequency component；
Generator and the first amplifier connect, and generator sends described power frequency component to first amplifier, amplify first
Producing a predeterminated voltage signal in device, the first amplifier is connected with current lifting device and booster respectively, and the first amplifier is by institute
State predeterminated voltage signal and send current lifting device and booster to；
Current lifting device is connected with sampled current transformer, and the predeterminated voltage signal that the first amplifier is sent here by current lifting device generates one
Current signal, and exported by outfan To and Tx on current lifting device, described current signal is become by sampled current transformer
Sampled signal is become to deliver to signal synthesis circuit；
Booster is connected with sampling voltage transformer, and the predeterminated voltage signal that the first amplifier is sent here by booster generates one
Voltage signal, and exported by outfan a and x on booster, described voltage signal is become by sampling voltage transformer
Sampled signal delivers to signal synthesis circuit；
Sampled current transformer and sampling voltage transformer are connected with signal synthesis circuit respectively, signal synthesis circuit and second
Amplifier connects, and the sampled signal that sampled current transformer or sampling voltage transformer are sent here is just being carried out by signal synthesis circuit
Hand over phase shift 90 degree, the most orthogonal dividing potential drop；Synchronous signal combiner circuit is by sampled current transformer or sampling voltage transformer
The sampled signal sent here carries out homophase dividing potential drop, finally homophase dividing potential drop and orthogonal voltage division signal is carried out signal syntheses, and passes through
Outfan K and the D output of the second amplifier；
Microprocessor is connected with the second amplifier, signal synthesis circuit and touch display screen respectively, by touching display screen
Upper manipulation microprocessor sends instruction to generator, the second amplifier, signal synthesis circuit, it is achieved output signal from
Dynamic regulation.
Numeral partial pressure type mutual inductor tester whole body assay device the most according to claim 1, it is characterised in that also
Measuring feedback circuit including one, described measurement feedback circuit is by the 3rd amplifier, wave filter, AD637 transducer and A/D
Transducer forms, and the 3rd amplifier is connected with the outfan of sampled current transformer and sampling voltage transformer, and the 3rd amplifies
Device is connected with wave filter, and wave filter is connected with AD637 transducer, and AD637 transducer is connected with A/D converter, A/D
Transducer is connected with microprocessor；Measure feedback circuit by sampled signal Real-time Feedback to microprocessor, it is ensured that be output as perseverance
Stream constant voltage signal.
Numeral partial pressure type mutual inductor tester whole body assay device the most according to claim 1, it is characterised in that institute
The signal synthesis circuit stated by follower, the first phase inverter, the second phase inverter, the phase shifter, anti-phase amplitude modulator, first point
Depressor, the second potentiometer, the first relay, the second relay and adder；Follower respectively with the first phase inverter and
Two phase inverters connect；Sampled signal drives through follower and delivers to the first phase inverter and the second phase inverter respectively；
First phase inverter is connected with two the first potentiometer respectively by the first relay, and sampled signal produces through the first phase inverter
Raw in-phase component-f and in-phase component+f, in-phase component-f receive the normally opened end of the first relay, and in-phase component+f receives the
The normal-closed end of one relay, in-phase component ± f is selected to deliver to the Voltage Reference of two the first potentiometer respectively by the first relay
Benchmark Vref end；
Second phase inverter is connected with phase shifter and anti-phase amplitude modulator successively by the second relay, and anti-phase amplitude modulator is respectively with two
Individual second potentiometer connects, and sampled signal produces-& quadrature component and+& quadrature component ,-& quadrature component through the second phase inverter
Receiving the normally opened end of the second relay ,+& quadrature component receives the normal-closed end of the second relay, and ± & quadrature component is by relay
Device selects to deliver to phase shifter phase shift 90 degree and produces quadrature component, and the most inverted amplitude modulator of quadrature component carries out anti-phase and amplitude tune
Whole, it is then sent through the voltage reference Vref end of two the second potentiometer；
First potentiometer and the second potentiometer are all connected with microprocessor, and the first potentiometer and the second potentiometer are all and adder
Connecting, described in-phase component ± f is closed by adder after the second potentiometer through the first potentiometer, ± & quadrature component
Become to deliver to the second amplifier to amplify.
Numeral partial pressure type mutual inductor tester whole body assay device the most according to claim 3, it is characterised in that institute
The first potentiometer stated and the second potentiometer are by AD7545D/A transducer, operational amplifier, data latches and address
Decoder form, address decoder is connected with data latches and AD7545D/A transducer respectively, data latches and
AD7545D/A transducer connect, AD7545D/A transducer is connected with operational amplifier, microprocessor respectively with data
Latch, address decoder and AD7545D/A transducer connect, in-phase component ± f two the first potentiometer of connection, ±
& quadrature component connects two the second potentiometer can improve the resolution of dividing potential drop, and AD7545D/A transducer is at microprocessor
Under control, in-phase component ± f and ± & quadrature component are decomposed into D*Vref/224, wherein D is 0～224。
Numeral partial pressure type mutual inductor tester whole body assay device the most according to claim 1, it is characterised in that institute
The generator stated is numerical control power frequency component generator, and it uses amplifier employing to have stream, overheated, the OPA of overvoltage protection
Integrated amplifier forms.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620305227.1U CN205720627U (en) | 2016-04-13 | 2016-04-13 | Numeral partial pressure type mutual inductor tester whole body assay device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620305227.1U CN205720627U (en) | 2016-04-13 | 2016-04-13 | Numeral partial pressure type mutual inductor tester whole body assay device |
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| Publication Number | Publication Date |
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| CN205720627U true CN205720627U (en) | 2016-11-23 |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107202970A (en) * | 2017-05-05 | 2017-09-26 | 中国电力科学研究院 | A kind of method of adjustment and device for AC potentiometer output voltage signal |
| CN108241138A (en) * | 2018-01-26 | 2018-07-03 | 黄建钟 | The detection device and detecting system of a kind of electric mutual inductor |
| CN110850353A (en) * | 2019-12-13 | 2020-02-28 | 国网湖北省电力有限公司计量中心 | Calibration method of instrument checking device of mutual inductor |
| CN111289783A (en) * | 2019-12-31 | 2020-06-16 | 清研电气（武汉）有限公司 | Whole check device calibrator and calibration circuit thereof |
| CN114062753A (en) * | 2021-12-02 | 2022-02-18 | 山西互感器电测设备有限公司 | Full-automatic voltage source simulation load zeroing box and testing method thereof |
-
2016
- 2016-04-13 CN CN201620305227.1U patent/CN205720627U/en active Active
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107202970A (en) * | 2017-05-05 | 2017-09-26 | 中国电力科学研究院 | A kind of method of adjustment and device for AC potentiometer output voltage signal |
| CN108241138A (en) * | 2018-01-26 | 2018-07-03 | 黄建钟 | The detection device and detecting system of a kind of electric mutual inductor |
| CN108241138B (en) * | 2018-01-26 | 2023-11-21 | 黄建钟 | Detection device and detection system of electronic transformer |
| CN110850353A (en) * | 2019-12-13 | 2020-02-28 | 国网湖北省电力有限公司计量中心 | Calibration method of instrument checking device of mutual inductor |
| CN111289783A (en) * | 2019-12-31 | 2020-06-16 | 清研电气（武汉）有限公司 | Whole check device calibrator and calibration circuit thereof |
| CN114062753A (en) * | 2021-12-02 | 2022-02-18 | 山西互感器电测设备有限公司 | Full-automatic voltage source simulation load zeroing box and testing method thereof |
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