CN1430069A - Method and device for testing current ratio staudard high-correctness current transformer - Google Patents
Method and device for testing current ratio staudard high-correctness current transformer Download PDFInfo
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- CN1430069A CN1430069A CN 02154187 CN02154187A CN1430069A CN 1430069 A CN1430069 A CN 1430069A CN 02154187 CN02154187 CN 02154187 CN 02154187 A CN02154187 A CN 02154187A CN 1430069 A CN1430069 A CN 1430069A
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Abstract
A method and device for testing the current proportion standard type high-correctness current transformer features that a microprocessor is used to analyze the data about zero test signal of test winding to generate automatic compensation signal of zero magnetic-flux, or a inverter is used to process the difference signal to obtain the compensation signal. Its advantages are no need of manual switching-over and no interference from frequency of power supply.
Description
Technical field
The present invention relates to a kind of transducer check method and device, relate in particular to a kind of pin-point accuracy current transformer calibration method and device that adopts current ratio standard to make benchmark, belong to the electric energy metrical field.
Background technology
Prior art is for example: the mutual inductor that Zhao Xiumin writes is from book " current ratio standard ", various current ratio standards have wherein been introduced as two-stage current transformer, current comparator, zero-flux current transformer, and transformer calibrating device, it measures the loop and the compensating signal output loop all is to adopt electrician's formula mimic channel form, need twice range estimation of experience manual adjustments balance, once regulate zero magnetic flux, once survey error, when " zeroing " and " measurement " and the equal nulling of zero indicator, reading is only correct, two processes must be carried out in the timesharing switching, this method of calibration complicated operation, expend time in, the zeroing load of calibrating installation use simultaneously contains capacitive load, is subjected to supply frequency easily and disturbs, when extraneous supply frequency fluctuation is big, will aggravate the difficulty that returns to zero.
Summary of the invention
The purpose of this invention is to provide a kind of new current ratio standard formula pin-point accuracy ct calibrating method and device, using the compensation zeroing of this calibration method and device and error measure process all to need not manual intervention can finish in the short period of time automatically, and is not subjected to that supply frequency is disturbed, the accuracy height.
The solution of the present invention is: a kind of current ratio standard formula pin-point accuracy ct calibrating method, with a current ratio standard 1 as benchmark, a winding polarity end of tested pin-point accuracy current transformer 2 links to each other with a winding polarity end of current ratio standard 1, current lifting device 3 is to a winding non-polar end input primary current signal of tested pin-point accuracy current transformer 2 and current ratio standard 1, the Secondary Winding polar end of tested pin-point accuracy current transformer 2 and the Secondary Winding of current ratio standard 1, compensation winding N
BPolar end link to each other, extract tested reference current signal T by the secondary load behind the tested pin-point accuracy current transformer 2 secondary non-polar ends 4
x, extract canonical reference current signal T by the secondary non-polar end of current ratio standard 1
0, extracting difference signal K by the Secondary Winding of tested pin-point accuracy current transformer 2 and the common port of current ratio standard 1 Secondary Winding, earth terminal is D, above-mentioned signal is delivered to tester 5 and is handled, compensation winding N
BThe loop Burden box that need not return to zero,
A when current ratio standard 1 is zero-flux current transformer or current comparator, utilizes microprocessor to pass through detecting winding N
DNulling detection signal J
UCarry out data analysis, generate adjustable digital form zero flux compensation signal, and then the automatic compensating signal B that converts analog quantity to outputs to the compensating coil N of current ratio standard 1
BCarrying out zero magnetic flux compensates automatically;
B when current ratio standard 1 is two-stage current transformer, adopts phase inverter 21 that difference signal K is exported signal B by way of compensation after equivalent anti-phase, and outputs to the compensating coil N of current ratio standard 1
BAutomatically compensate;
In the above-mentioned calibration method, when current ratio standard 1 is zero-flux current transformer or current comparator, adopted phase inverter 21 that equivalent being superimposed on the compensating signal after anti-phase of difference signal K exported, as the zero automatic compensating signal B of magnetic flux.
Use the current ratio standard formula pin-point accuracy transformer calibrating device of said method, by current ratio standard 1, current lifting device 3, secondary load 4 and tester 5 are formed, tester 5 is by reference current sample circuit 6, amplification filtering circuit 7,90 ° of phase-shift circuits 8,90 ° keep phase discriminator 9,0 ° of phase-shift circuit 10,0 ° keeps phase discriminator 11, difference signal sample circuit 12, amplification filtering circuit 13, sampling hold circuit 14, A/D change-over circuit 15, microprocessor 16, amplification filtering rectification circuit 17, in-phase component D/A change-over circuit 18, quadrature component D/A change-over circuit 19, adding circuit 20, phase inverter 21 and signal amplification output circuit 22 are formed; The input end of difference signal sample circuit 12 is inserted at difference signal K and D two ends, and the output of difference signal sample circuit 12 links to each other with the input end of sampling hold circuit 14 with A/D change-over circuit 15 through amplification filtering circuit 13; Reference current signal end T
xAnd T
0Connect the input end of reference current sample circuit 6, the output of reference current sample circuit 6 links to each other through the input end of amplification filtering circuit 7 with 90 ° of phase-shift circuits 8 and 0 ° of phase-shift circuit 10; The output of 90 ° of phase-shift circuits 8 links to each other with a data input port of microprocessor 16 through 90 ° of maintenance phase discriminators 9, and the output of 90 ° of phase-shift circuits 8 also links to each other with the control input end of quadrature component D/A change-over circuit 19; The output of 0 ° of phase-shift circuit 10 links to each other with another data input port of microprocessor 16 through 0 ° of maintenance phase discriminator 11, and the output of 0 ° of phase-shift circuit 10 also links to each other with the control input end of in-phase component D/A change-over circuit 18 and the input end of A/D change-over circuit 15; Nulling detection signal J
UConnect the input end of amplification filtering rectification circuit 17, the output of amplification filtering rectification circuit 17 connects the input of A/D change-over circuit 15; The data bus input end of microprocessor 16 is delivered in the data output of A/D change-over circuit 15, the data bus output of microprocessor 16 connects the data input pin of in-phase component D/A change-over circuit 18 and quadrature component D/A change-over circuit 19, the output of in-phase component D/A change-over circuit 18 and quadrature component D/A change-over circuit 19 connects the input of adding circuit 20, the input end of phase inverter 21 is introduced the signal from difference signal K and D two ends, adding circuit 20 is received in the output of phase inverter 21, and the output signal of adding circuit 20 is automatic compensating signal B after signal amplification circuit 22 amplifies.
Above-mentioned current ratio standard formula pin-point accuracy transformer calibrating device, the difference signal sample circuit 12 in its tester 5 reach the I/V change-over circuit 24 that 0.1 current transformer 23 and operational amplifier be main body by class of accuracy and form.
Above-mentioned current ratio standard formula pin-point accuracy transformer calibrating device, the equivalent input impedance of its difference signal sample circuit 12 is smaller or equal to 0.02 Ω.
It is by to detecting winding N for current comparator and zero-flux current transformer class current ratio standard that the present invention utilizes microprocessor
DNulling detection signal J
UData analysis generates the zero flux compensation signal of automatic and adjustable; Equate but the automatic compensating signal B realization compensation automatically of opposite in sign for automatic generation of two-stage current transformer class current ratio standard with difference signal K absolute value, error of measurement loop K, be low input impedance between the D terminal, make " zeroing " and " measurement " work can not need manual switchover simultaneously.Burden box does not promptly have capacitive load owing to need not return to zero, and the process that then returns to zero is not disturbed by supply frequency, and verification process can be finished in very short time automatically, has reduced labour intensity and has saved the plenty of time.The present invention is used for examining and determine 0.01 grade and other pin-point accuracy current transformer of higher level specially, accuracy can reach: in-phase component error delta X=± (2%X+2%Y+2 word), quadrature component error delta Y=± (2%X+2%Y+5 word), X is the in-phase component measured value, and Y is the quadrature component measured value.
Description of drawings
The calibrating wiring diagram of Fig. 1 current ratio standard formula pin-point accuracy transformer calibrating device;
Fig. 2 is the theory diagram of tester in the current ratio standard formula pin-point accuracy transformer calibrating device.
Embodiment
Below in conjunction with accompanying drawing the present invention is described in further detail.
Among Fig. 1, current ratio standard 1 is zero magnetic flux two-stage current transformer, a winding polarity end of tested pin-point accuracy current transformer 2 links to each other with a winding polarity end of current ratio standard 1, current lifting device 3 is to a winding non-polar end input primary current signal of tested pin-point accuracy current transformer 2 and current ratio standard 1, the Secondary Winding polar end of tested pin-point accuracy current transformer 2 and the Secondary Winding of current ratio standard 1, compensation winding N
BPolar end link to each other, extract tested reference current signal T by the secondary load behind the tested pin-point accuracy current transformer 2 secondary non-polar ends 4
x, extract canonical reference current signal T by the secondary non-polar end of current ratio standard 1
0, extracting difference signal K by the Secondary Winding of tested pin-point accuracy current transformer 2 and the public polar end of current ratio standard 1 Secondary Winding, earth terminal is D, above-mentioned signal is delivered to tester 5 and is handled, compensation winding N
BThe loop Burden box that need not return to zero, but utilize microprocessor with program mode (PM) by to detecting winding N
DNulling detection signal J
UCarry out data analysis, generate adjustable digital form zero flux compensation signal, and then the automatic compensating signal that converts analog quantity to is exported, also be superimposed to that output is re-used as the zero automatic compensating signal B of magnetic flux on the compensating signal after anti-phase with difference signal K is equivalent simultaneously, the full remuneration that influences that difference signal K, D terminal potential difference are brought the zeroing process can be fallen like this with phase inverter 21.
In Fig. 2, difference signal K and D isolate input through current transformer 23, the class of accuracy of current transformer 23 reaches 0.1, I/V change-over circuit 24 is operational amplification circuits, the difference signal sample circuit 12 that both combine makes between difference input end K, D lower equivalent input impedance, its impedance has been satisfied zero magnetic flux condition substantially smaller or equal to 0.02 Ω, can carry out simultaneously to guarantee zeroing and surveying work; Difference signal is converted to voltage signal through I/V change-over circuit 24, carries out signal by difference amplification filtering circuit 13 again and amplifies and filtering, is input to the input end of A/D change-over circuit 15 behind sampling hold circuit 14; A/D change-over circuit 15 becomes analog signal conversion the data bus of delivering to microprocessor 16 after the digital signal; Reference current signal T
xAnd T
0Through reference current sample circuit 6, output voltage signal is to amplification filtering circuit 7, to 0 ° of data input port that keeps phase discriminator 11 arrive microprocessor 16 again, another data input ports of microprocessor 16 are arrived to 90 ° of maintenance phase discriminators 9 in another road to the output signal one tunnel of amplification filtering circuit 7 again behind 90 ° of phase-shift circuits 8 behind 0 ° of phase-shift circuit 10; 0 ° of phase-shift circuit 10 output signal also arrives microprocessor 16 output percentage tabular values again behind A/D converter 15; Nulling detection signal J
UOutput to A/D change-over circuit 15 through amplification filtering rectification circuit 17, carry out after the analog to digital conversion output digital form nulling detection signal to microprocessor 16, for the generation of the compensating signal that returns to zero provides real time detection signal by A/D converter; Microprocessor 16 carries out data processing according to the signal from 0 ° of maintenance phase discriminator 11 and 90 ° of maintenance phase discriminators 9 in the reference current loop to the signal from A/D change-over circuit 15, calculate in-phase component and quadrature component and output to display circuit display error value, simultaneously, microprocessor 16 carries out data processing according to A/D change-over circuit 15 analog-to-digital nulling signals, generate and output two-way adjusted digital signal (in-phase component of compensating signal and quadrature component), 18 work of 0 ° of phase-shift circuit 10 output signals control in-phase component D/A converter, 19 work of 90 ° of phase-shift circuit 8 output signals control quadrature component D/A converters, the analog output signal of two-way D/A converter carries out superposition by adding circuit 20; Phase inverter 21 outputs to adding circuit 20 after with difference signal K and the anti-phase processing of D, be superimposed on the analog output signal from two-way D/ A converter 18,19, making difference signal K is zero to the potential difference (PD) of compensating signal B, the influence that further compensate for poor value signal K above earth potential is produced; The signal that signal amplification circuit 22 is exported adding circuit 20 carries out power amplification makes it have certain load capacity, and its output is automatic compensating signal B.
Claims (5)
1. current ratio standard formula pin-point accuracy ct calibrating method, with a current ratio standard (1) as benchmark, a winding polarity end of tested pin-point accuracy current transformer (2) links to each other with a winding polarity end of current ratio standard (1), current lifting device (3) is to a winding non-polar end input primary current signal of tested pin-point accuracy current transformer (2) and current ratio standard (1), the Secondary Winding of the Secondary Winding polar end of tested pin-point accuracy current transformer (2) and current ratio standard (1) and compensation winding N
BPolar end link to each other, extract tested reference current signal T by the secondary load (4) behind tested pin-point accuracy current transformer (2) the secondary non-polar end
x, extract canonical reference current signal T by the secondary non-polar end of current ratio standard 1
0, extracting difference signal K by the Secondary Winding of tested pin-point accuracy current transformer (2) and the common port of current ratio standard (1) Secondary Winding, earth terminal is D, above-mentioned signal is delivered to tester (5) and is handled, and it is characterized in that: compensation winding N
BThe loop Burden box that need not return to zero,
A when current ratio standard (1) is zero-flux current transformer or current comparator, utilizes microprocessor to pass through detecting winding N
DNulling detection signal J
UCarry out data analysis, generate adjustable digital form zero flux compensation signal, and then the automatic compensating signal B that converts analog quantity to outputs to the compensating coil N of current ratio standard (1)
BCarrying out zero magnetic flux compensates automatically;
B when current ratio standard (1) is two-stage current transformer, adopts phase inverter (21) that the equivalent inversion signal of difference signal K is exported signal B by way of compensation, and outputs to the compensating coil N of current ratio standard (1)
BAutomatically compensate.
2. according to claim 1 described calibration method, it is characterized in that: when current ratio standard (1) is zero-flux current transformer or current comparator, adopt phase inverter (21) to be superimposed to after anti-phase on the compensating signal as the zero automatic compensating signal B of magnetic flux difference signal K is equivalent, outputed to the compensation winding of current ratio standard (1) again.
3. current ratio standard formula pin-point accuracy transformer calibrating device of using said method, by current ratio standard (1), current lifting device (3), secondary load (4) and tester (5) are formed, and tester (5) is by reference current sample circuit (6), amplification filtering circuit (7), 90 ° of phase-shift circuits (8), 90 ° keep phase discriminator (9), 0 ° of phase-shift circuit (10), 0 ° keeps phase discriminator (11), difference signal sample circuit (12), amplification filtering circuit (13), sampling hold circuit (14), A/D change-over circuit (15), microprocessor (16), amplification filtering rectification circuit (17), in-phase component D/A change-over circuit (18), quadrature component D/A change-over circuit (19), adding circuit (20), phase inverter (21) and signal amplification output circuit (22) are formed; The input end of difference signal sample circuit (12) is inserted at difference signal K and D two ends, and the output of difference signal sample circuit (12) links to each other with the input end of sampling hold circuit (14) with A/D change-over circuit (15) through amplification filtering circuit (13); Reference current signal end T
xAnd T
0Connect the input end of reference current sample circuit (6), the output of reference current sample circuit (6) links to each other through the input end of amplification filtering circuit (7) with 90 ° of phase-shift circuits (8) and 0 ° of phase-shift circuit (10); The output of 90 ° of phase-shift circuits (8) links to each other with a data input port of microprocessor (16) through 90 ° of maintenance phase discriminators (9), and the output of 90 ° of phase-shift circuits (8) also links to each other with the control input end of quadrature component D/A change-over circuit (19); The output of 0 ° of phase-shift circuit (10) links to each other with another data input port of microprocessor (16) through 0 ° of maintenance phase discriminator (11), and the output of 0 ° of phase-shift circuit (10) also links to each other with the control input end of in-phase component D/A change-over circuit (18) and the input end of A/D change-over circuit (15); Nulling detection signal J
UConnect the input end of amplification filtering rectification circuit (17), the output of amplification filtering rectification circuit (17) connects the input of A/D change-over circuit (15); The data bus input end of microprocessor (16) is delivered in the data output of A/D change-over circuit (15), the data bus output of microprocessor (16) connects the data input pin of in-phase component D/A change-over circuit (18) and quadrature component D/A change-over circuit (19), the output of in-phase component D/A change-over circuit (18) and quadrature component D/A change-over circuit (19) connects the input of adding circuit (20), the input end of phase inverter (21) is introduced the signal from difference signal K and D two ends, adding circuit (20) is received in the output of phase inverter (21), and the output signal of adding circuit (20) is automatic compensating signal B after signal amplification circuit (22) amplifies.
4. according to claim 3 described current ratio standard formula pin-point accuracy transformer calibrating devices, it is characterized in that: the difference signal sample circuit (12) in the tester (5) reaches the I/V change-over circuit (24) that 0.1 current transformer (23) and operational amplifier be main body by class of accuracy and forms.
5. according to claim 4 described current ratio standard formula pin-point accuracy transformer calibrating devices, the equivalent input impedance of its difference signal sample circuit (12) is smaller or equal to 0.02 Ω.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02154187 CN1430069A (en) | 2002-12-31 | 2002-12-31 | Method and device for testing current ratio staudard high-correctness current transformer |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02154187 CN1430069A (en) | 2002-12-31 | 2002-12-31 | Method and device for testing current ratio staudard high-correctness current transformer |
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| CN1430069A true CN1430069A (en) | 2003-07-16 |
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| CN 02154187 Pending CN1430069A (en) | 2002-12-31 | 2002-12-31 | Method and device for testing current ratio staudard high-correctness current transformer |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2008083610A1 (en) * | 2007-01-06 | 2008-07-17 | Huabin Zhao | A current measuring device and a calibration method for the same |
| CN100432693C (en) * | 2004-03-30 | 2008-11-12 | 武汉市龙成电气设备厂 | Method of self-calibrating of current ratio standard device |
| CN1963556B (en) * | 2006-11-24 | 2010-04-14 | 中国计量科学研究院 | Apparatus for integrality checking proportion of cryo-current comparator and the method thereof |
| CN103293507A (en) * | 2012-03-02 | 2013-09-11 | 北京瑞恒超高压电器研究所 | Online detection method of error of current transformer |
| WO2014008707A1 (en) * | 2012-07-13 | 2014-01-16 | 天门市电工仪器仪表研究所 | Ratio error self calibration system for miniature current transformer |
| CN103823100A (en) * | 2013-07-29 | 2014-05-28 | 中国计量科学研究院 | High-accuracy current comparator and self-checking method |
| CN105372614A (en) * | 2015-12-07 | 2016-03-02 | 国网电力科学研究院武汉南瑞有限责任公司 | Electronic type automatic zero-setting method and device |
| CN113030837A (en) * | 2021-03-04 | 2021-06-25 | 青岛鼎信通讯股份有限公司 | Full-range current output module and method based on electric energy meter calibrating device |
| 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 |
| CN114814704A (en) * | 2022-04-15 | 2022-07-29 | 中国计量科学研究院 | Error compensation method for standard voltage transformer |
| CN118131111A (en) * | 2024-05-06 | 2024-06-04 | 云南电网有限责任公司 | Online monitoring device, method, terminal and storage medium for error characteristics of mutual inductor |
-
2002
- 2002-12-31 CN CN 02154187 patent/CN1430069A/en active Pending
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100432693C (en) * | 2004-03-30 | 2008-11-12 | 武汉市龙成电气设备厂 | Method of self-calibrating of current ratio standard device |
| CN1963556B (en) * | 2006-11-24 | 2010-04-14 | 中国计量科学研究院 | Apparatus for integrality checking proportion of cryo-current comparator and the method thereof |
| WO2008083610A1 (en) * | 2007-01-06 | 2008-07-17 | Huabin Zhao | A current measuring device and a calibration method for the same |
| CN103293507B (en) * | 2012-03-02 | 2016-08-31 | 北京瑞恒超高压电器研究所(普通合伙) | The online test method of current transformer error |
| CN103293507A (en) * | 2012-03-02 | 2013-09-11 | 北京瑞恒超高压电器研究所 | Online detection method of error of current transformer |
| CN103543428B (en) * | 2012-07-13 | 2017-01-25 | 天门市电工仪器仪表研究所 | Miniature current transformer ratio error self-calibration system |
| CN103543428A (en) * | 2012-07-13 | 2014-01-29 | 天门市电工仪器仪表研究所 | Miniature current transformer ratio error self-calibration system |
| WO2014008707A1 (en) * | 2012-07-13 | 2014-01-16 | 天门市电工仪器仪表研究所 | Ratio error self calibration system for miniature current transformer |
| CN103823100A (en) * | 2013-07-29 | 2014-05-28 | 中国计量科学研究院 | High-accuracy current comparator and self-checking method |
| CN105372614A (en) * | 2015-12-07 | 2016-03-02 | 国网电力科学研究院武汉南瑞有限责任公司 | Electronic type automatic zero-setting method and device |
| CN113030837A (en) * | 2021-03-04 | 2021-06-25 | 青岛鼎信通讯股份有限公司 | Full-range current output module and method based on electric energy meter calibrating device |
| 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 |
| CN114814704A (en) * | 2022-04-15 | 2022-07-29 | 中国计量科学研究院 | Error compensation method for standard voltage transformer |
| CN118131111A (en) * | 2024-05-06 | 2024-06-04 | 云南电网有限责任公司 | Online monitoring device, method, terminal and storage medium for error characteristics of mutual inductor |
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