CN201477203U - Capacitor type voltage transformer accuracy checking device - Google Patents
Capacitor type voltage transformer accuracy checking device Download PDFInfo
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- CN201477203U CN201477203U CN2009202076029U CN200920207602U CN201477203U CN 201477203 U CN201477203 U CN 201477203U CN 2009202076029 U CN2009202076029 U CN 2009202076029U CN 200920207602 U CN200920207602 U CN 200920207602U CN 201477203 U CN201477203 U CN 201477203U
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Abstract
The utility model relates to a capacitor type voltage transformer accuracy checking device comprising a voltage regulating booster, a capacitor type voltage ratio standard device and an error measuring device, wherein the capacitor type voltage ratio standard device is connected with two output ends of the voltage regulating booster, one output end of the voltage regulating booster is earthed, a checked capacitor type voltage transformer is connected to a relative terminal of the capacitor type voltage ratio standard device, and the error measuring device is respectively connected with capacitor type voltage ratio standard device and the checked capacitor type voltage transformer. The capacitor type voltage transformer accuracy checking device is capable of applying on-site checking to the capacitor type voltage transformer with high accuracy, which is quite convenient and effective, and therefore the checking device is suitable for checking accuracy of capacitor type voltage transformer of 220kv and below, and 0.2 grades and below.
Description
Technical field
The utility model relates to the electric system metering field, relates in particular to a kind of capacitance type potential transformer accuracy calibration equipment.
Background technology
At present in the electric system of 220kV widespread use be electromagnetic potential transformer; but along with electric system develops to high capacity, high-tension direction; factory, stand and system digitalized measurement, protection, scheduling and control have become the trend of development, the requirement of this miniaturization that power equipment is proposed, intellectuality, high reliability is also more and more higher.Existing electromagnetic potential transformer is because the deficiency of its design feature and existence can not satisfy this requirement.
Compare with 220kV traditional electrical magnetic inductive voltage transformer (VT), capacitance type potential transformer has following series of advantages: good insulating property and cheap price; One sub-high pressure does not contain iron core, has eliminated problems such as magnetic saturation and ferroresonance; Anti-electromagnetic interference performance is good; Dynamic range is big, the measuring accuracy height; Frequency response range is wide; Not danger such as inflammable, the explosive that produces because of trapped fuel; Volume is little, in light weight, conserve space; The trend that adapts to electric-power metering and protection microcomputerization and automation development.Capacitance type potential transformer has become the substitute products of traditional 220kV electromagnetic potential transformer, is used widely in the 220kV power industry.
Capacitance type potential transformer is the source of high pressure measurement, and the whether accurate accuracy that directly has influence on electric energy metrical of its work is related to the great economic benefit of all departments, and the accuracy verification of capacitance type potential transformer does not also have highly effective method at present.
The utility model content
The purpose of this utility model is to provide a kind of capacitance type potential transformer accuracy calibration equipment, can implement field-checking to the accuracy of capacitance type potential transformer, and the accuracy height is very convenient, effective.
To achieve the above object, the utility model provides a kind of capacitance type potential transformer accuracy calibration equipment to comprise pressure regulation stepup transformer, capacitor voltage ratio standard device and error measuring means, described capacitor voltage ratio standard device is connected with two output terminals of pressure regulation stepup transformer, an and wherein output head grounding of described pressure regulation stepup transformer, tested capacitance type potential transformer is connected on the corresponding end of capacitor voltage ratio standard device, and described error measuring means is connected with capacitor voltage ratio standard device, tested capacitance type potential transformer respectively.
Above-mentioned capacitance type potential transformer accuracy calibration equipment, wherein, described pressure regulation stepup transformer comprises pressure regulator, driver transformer, impedor and capacitor; The positive and negative electrode power end of described pressure regulator is connected with external power source respectively, one end of the primary coil of described driver transformer is connected with the adjustable side of pressure regulator, the other end of this primary coil is connected with the negative power supply end of pressure regulator, be connected to the two ends of the secondary coil of driver transformer after described impedor and the capacitors in series, the junction of described impedor and capacitor forms an output terminal of pressure regulation stepup transformer, and the junction of the secondary coil of described capacitor and driver transformer forms another output terminal of pressure regulation stepup transformer, this output head grounding.
Above-mentioned capacitance type potential transformer accuracy calibration equipment, wherein, described capacitor voltage ratio standard device is made up of a high voltage standard capacitor and a low-voltage standards capacitors in series.
Above-mentioned capacitance type potential transformer accuracy calibration equipment, wherein, the positive pole of the high voltage standard capacitor of described capacitor voltage ratio standard device, the negative pole of low-voltage standards capacitor are connected with two output terminals of pressure regulation stepup transformer respectively, and the minus earth of described low-voltage standards capacitor.
Above-mentioned capacitance type potential transformer accuracy calibration equipment, wherein, described low-voltage standards capacitor is that polydisc can be debugged capacitor.
Above-mentioned capacitance type potential transformer accuracy calibration equipment, wherein, described tested capacitance type potential transformer comprises first capacitor, second capacitor, electromagnetic potential transformer and compensation reactor; Described first capacitor and second capacitors in series form capacitive divider, and an end of described compensation reactor is connected with the negative pole of first capacitor; The two ends of the primary coil of described electromagnetic potential transformer are connected with the other end of compensation reactor, the negative pole of second capacitor respectively, the secondary coil offered load of described electromagnetic potential transformer.
Above-mentioned capacitance type potential transformer accuracy calibration equipment, wherein, the positive pole of first capacitor of described tested capacitance type potential transformer, the negative pole of second capacitor are connected with two output terminals of pressure regulation stepup transformer respectively, and the minus earth of described second capacitor.
Above-mentioned capacitance type potential transformer accuracy calibration equipment, wherein, the earth terminal ground connection of described error measuring means, the standard signal input end of this error measuring means is connected with the positive pole of the low-voltage standards capacitor of capacitor voltage ratio standard device, and the positive pole of the load that is connected with tested capacitance type potential transformer is connected with the measured signal input end of this error measuring means.
The circuit that the utility model capacitance type potential transformer accuracy calibration equipment adopts pressure regulation stepup transformer, capacitor voltage ratio standard device and error measuring means to form has been realized the accuracy of field-checking measured capacitance formula voltage transformer (VT), has filled up the accuracy blank technically of verification measured capacitance formula voltage transformer (VT); The pressure regulation stepup transformer adopts tandem resonance step-up source, has little, the lightweight characteristics of volume, very is suitable for on-the-spot the use; The low-voltage standards capacitor of capacitor voltage ratio standard device adopts polydisc can debug capacitor, can realize being complementary with the rated voltage no-load voltage ratio of different tested capacitance type potential transformers; Before each field-checking, adopt the standard potential transformer and the normal voltage inductive voltage divider of pin-point accuracy that the dividing potential drop coefficient ratio of capacitor voltage ratio standard device is calibrated, the ratio of standard potential transformer is passed to capacitor voltage ratio standard device, improved the accuracy and the validity of verification.
Description of drawings
Capacitance type potential transformer accuracy calibration equipment of the present utility model is provided by following embodiment and accompanying drawing.
Fig. 1 is the circuit structure diagram of the utility model capacitance type potential transformer accuracy calibration equipment.
Fig. 2 is the synoptic diagram that polydisc can be debugged capacitor in the utility model.
Fig. 3 is the circuit diagram of field calibration capacitor voltage ratio standard device intrinsic standoff ratio coefficient in the utility model.
Embodiment
Below with reference to Fig. 1～Fig. 3 capacitance type potential transformer accuracy calibration equipment of the present utility model and method of calibration are described in further detail.
See also Fig. 1, capacitance type potential transformer accuracy calibration equipment comprises pressure regulation stepup transformer 1, capacitor voltage ratio standard device 2, error measuring means 3 and tested capacitance type potential transformer 4.
Described pressure regulation stepup transformer 1 provides voltage for capacitor voltage ratio standard device 2 and tested capacitance type potential transformer 4, the normal voltage of 3 pairs of capacitor voltage ratio standards of described error measuring means device 2 and the tested voltage of secondary of tested capacitance type potential transformer 4 are measured, comparison, thereby measure the ratio difference and the angular difference value of tested capacitance type potential transformer 4, whether meet DL/T448-2000 " electric power meter rule of management " for the accuracy of judging tested capacitance type potential transformer 4 and require to use, realize verification tested capacitance type potential transformer 4 accuracy with this.
The tandem resonance step-up source that described pressure regulation stepup transformer 1 is made up of pressure regulator TD, driver transformer T, impedor L2 and capacitor C3.Described pressure regulator TD just, the negative power supply end is connected with external power source respectively, one end of the primary coil of described driver transformer T is connected with the adjustable side A of pressure regulator TD, the other end of this primary coil is connected with the negative power supply end of pressure regulator TD, be connected to the two ends of the secondary coil of driver transformer T after described impedor L2 and the capacitor C3 series connection, the junction of described impedor L2 and capacitor C3 forms an output terminal H of pressure regulation stepup transformer 1, and the junction of the secondary coil of described capacitor C3 and driver transformer T forms another output terminal E of pressure regulation stepup transformer 1, this output terminal E ground connection.
The advantage in tandem resonance step-up source can satisfy the requirement of big capacity load for the power supply that only needs to use low capacity, and himself volume is little, in light weight, very is suitable for on-the-spot the use.
Described capacitor voltage ratio standard device 2 is composed in series by a high voltage standard capacitor C10 and a low-voltage standards capacitor C20.Two output terminal H and E of pressure regulation stepup transformer 1 are inserted in described high voltage standard capacitor C10 and low-voltage standards capacitor C20 series connection back, wherein, the anodal B of described high voltage standard capacitor C10 is connected with the output terminal H of pressure regulation stepup transformer 1, the anodal B of this high voltage standard capacitor C10 is the high-pressure side of capacitor voltage ratio standard device 2, the negative pole of described low-voltage standards capacitor C20 is connected with the output terminal E of pressure regulation stepup transformer 1, the anodal F of this low-voltage standards capacitor C20 is the intermediate voltage terminal of capacitor voltage ratio standard device 2, this intermediate voltage terminal is connected with the standard signal input end Un of error measuring means 3, is measured the standard voltage value of capacitor voltage ratio standard device 2 by error measuring means 3.
In the present embodiment, above-mentioned high voltage standard capacitor C10 adopts compressed gas condenser, and above-mentioned low-voltage standards capacitor C20 adopts dielectric capacitor.
Because the rated voltage no-load voltage ratio kind of tested capacitance type potential transformer 4 is more, therefore, the dividing potential drop coefficient of capacitor voltage ratio standard device 2 { K=C10/ (C10+C20) } kind also will adapt with it, above-mentioned low-voltage standards capacitor C20 can adopt polydisc can debug capacitor, as shown in Figure 2, be complementary with the rated voltage no-load voltage ratio of realization with the actual tested capacitance type potential transformer 4 that uses.
The accuracy of above-mentioned capacitor voltage ratio standard device 2 is keys of tested capacitance type potential transformer 4 accuracy of accurate verification, and the accuracy of capacitor voltage ratio standard device 2 is affected by environment bigger, (pass through the space capacitive coupling between capacitor voltage ratio standard device 2 and near the object as environment temperature, near object, can change self dividing potential drop coefficient), therefore, before field-checking being carried out in the accuracy of tested capacitance type potential transformer 4, to calibrate the intrinsic standoff ratio coefficient of above-mentioned capacitor voltage ratio standard device 2 earlier at every turn.
Be illustrated in figure 3 as the circuit theory diagrams of field calibration capacitor voltage ratio standard device 2 intrinsic standoff ratio coefficients, adopt the standard potential transformer PTo of pin-point accuracy and normal voltage inductive voltage divider IVD in the capacitor voltage ratio standard device 2, the low pressure stage intrinsic standoff ratio measures, whether the intrinsic standoff ratio coefficient that detects capacitor voltage ratio standard device 2 meets the rules requirement, if do not meet, then capacitor voltage ratio standard device 2 is finely tuned, so that the intrinsic standoff ratio coefficient of capacitor voltage ratio standard device 2 meets the rules requirement.
Described tested capacitance type potential transformer 4 comprises capacitor C1, capacitor C2, electromagnetic potential transformer PT and compensation reactor L1.Described capacitor C1 connects with capacitor C2 and forms capacitive divider, the two ends of this capacitive divider are connected with E with two output terminal H of pressure regulation stepup transformer 1 respectively, the positive pole that also is capacitor C1 is connected with the positive pole of the high voltage standard capacitor C10 of capacitor voltage ratio standard device 2, and the negative pole of capacitor C2 is connected with the negative pole of the low-voltage standards capacitor C20 of capacitor voltage ratio standard device 2.The end of described compensation reactor L1 is connected with the negative pole of capacitor C1.The two ends of the primary coil of described electromagnetic potential transformer PT are connected with the other end of compensation reactor L1, the negative pole of capacitor C2 respectively, the secondary coil offered load Zb of described electromagnetic potential transformer PT, the anodal G of described load Zb is connected with the measured signal input end Ux of error measuring means 3, by the tested magnitude of voltage of secondary of the tested capacitance type potential transformer 4 of error measuring means 3 measurements, the minus earth of described load Zb.
The anodal C of the capacitor C1 that is connected with the positive pole of high voltage standard capacitor C10 forms a high-pressure side of tested capacitance type potential transformer 4.
The earth terminal D ground connection of described error measuring means 3.Described error measuring means 3 is measured the normal voltage of capacitor voltage ratio standard device 2 and the tested voltage of secondary of tested capacitance type potential transformer 4, and these two magnitudes of voltage are compared, calculate and show the ratio difference of tested capacitance type potential transformer 4 and angular difference value (is two important referential datas in the capacitance type potential transformer error analysis than difference and angular difference value), whether the accuracy of judging tested capacitance type potential transformer 4 according to the ratio difference and the angular difference value of tested capacitance type potential transformer 4 meets the rules requirement, finishes the purpose of tested capacitance type potential transformer 4 accuracy of verification.
In the present embodiment, above-mentioned error measuring means 3 is a potential difference (PD) formula mutual-inductor tester.
In order to guarantee the accuracy of verification, the selection of each equipment should be satisfied following requirement:
(1), the accuracy grade of capacitor voltage ratio standard device should be than the accuracy grade of tested capacitance type potential transformer high two ranks, capacitor voltage ratio standard device actual error be no more than tested capacitance type potential transformer error limitation 1/5 (capacitor voltage ratio standard device also can be selected the high tested capacitance type potential transformer one-level of accuracy grade, but this moment, the error of calculating tested capacitance type potential transformer should be carried out the error correction of standard by the requirement of relevant regulations);
(2), the variation of capacitor voltage ratio standard device (voltage rises and the poor of twice measured error amount that descend) should satisfy the limit value of table 1;
Table 1: the variation restriction of capacitor voltage ratio standard device
(3), in the calibration interval, the error of capacitor voltage ratio standard device changes smaller or equal to 1/3 of the error limit value of tested capacitance type potential transformer;
(4) measuring error of error measuring means is smaller or equal to 1/10 of tested capacitance type potential transformer error limit value;
(5) measuring error that causes of error measuring means sensitivity is smaller or equal to tested capacitance type potential transformer error limit value 1/20;
(6) measuring error that causes of error measuring means minimum division value is smaller or equal to tested capacitance type potential transformer error limit value 1/15;
(7) measuring error of pressure regulation stepup transformer is smaller or equal to 1/10 of tested capacitance type potential transformer error limit value.
The utility model capacitance type potential transformer accuracy calibration equipment is for field-checking 220kV and accuracy following, 0.2 grade and following capacitance type potential transformer provide objective condition and technological means.
Claims (8)
1. capacitance type potential transformer accuracy calibration equipment, it is characterized in that, comprise pressure regulation stepup transformer, capacitor voltage ratio standard device and error measuring means, described capacitor voltage ratio standard device is connected with two output terminals of pressure regulation stepup transformer, an and wherein output head grounding of described pressure regulation stepup transformer, tested capacitance type potential transformer is connected on the corresponding end of capacitor voltage ratio standard device, and described error measuring means is connected with capacitor voltage ratio standard device, tested capacitance type potential transformer respectively.
2. capacitance type potential transformer accuracy calibration equipment as claimed in claim 1 is characterized in that described pressure regulation stepup transformer comprises pressure regulator, driver transformer, impedor and capacitor;
The positive and negative electrode power end of described pressure regulator is connected with external power source respectively, one end of the primary coil of described driver transformer is connected with the adjustable side of pressure regulator, the other end of this primary coil is connected with the negative power supply end of pressure regulator, be connected to the two ends of the secondary coil of driver transformer after described impedor and the capacitors in series, the junction of described impedor and capacitor forms an output terminal of pressure regulation stepup transformer, and the junction of the secondary coil of described capacitor and driver transformer forms another output terminal of pressure regulation stepup transformer, this output head grounding.
3. capacitance type potential transformer accuracy calibration equipment as claimed in claim 1 is characterized in that, described capacitor voltage ratio standard device is made up of a high voltage standard capacitor and a low-voltage standards capacitors in series.
4. capacitance type potential transformer accuracy calibration equipment as claimed in claim 3, it is characterized in that, the positive pole of the high voltage standard capacitor of described capacitor voltage ratio standard device, the negative pole of low-voltage standards capacitor are connected with two output terminals of pressure regulation stepup transformer respectively, and the minus earth of described low-voltage standards capacitor.
5. capacitance type potential transformer accuracy calibration equipment as claimed in claim 3 is characterized in that, described low-voltage standards capacitor is that polydisc can be debugged capacitor.
6. capacitance type potential transformer accuracy calibration equipment as claimed in claim 1 is characterized in that described tested capacitance type potential transformer comprises first capacitor, second capacitor, electromagnetic potential transformer and compensation reactor;
Described first capacitor and second capacitors in series form capacitive divider, and an end of described compensation reactor is connected with the negative pole of first capacitor; The two ends of the primary coil of described electromagnetic potential transformer are connected with the other end of compensation reactor, the negative pole of second capacitor respectively, the secondary coil offered load of described electromagnetic potential transformer.
7. capacitance type potential transformer accuracy calibration equipment as claimed in claim 6, it is characterized in that, the positive pole of first capacitor of described tested capacitance type potential transformer, the negative pole of second capacitor are connected with two output terminals of pressure regulation stepup transformer respectively, and the minus earth of described second capacitor.
8. capacitance type potential transformer accuracy calibration equipment as claimed in claim 1, it is characterized in that, the earth terminal ground connection of described error measuring means, the standard signal input end of this error measuring means is connected with the positive pole of the low-voltage standards capacitor of capacitor voltage ratio standard device, and the positive pole of the load that is connected with tested capacitance type potential transformer is connected with the measured signal input end of this error measuring means.
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| CN2009202076029U CN201477203U (en) | 2009-08-07 | 2009-08-07 | Capacitor type voltage transformer accuracy checking device |
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| CN2009202076029U CN201477203U (en) | 2009-08-07 | 2009-08-07 | Capacitor type voltage transformer accuracy checking device |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101872007A (en) * | 2010-06-10 | 2010-10-27 | 江西省电力科学研究院 | Three-phase voltage transformer verification method based on voltage transformer load error curve extrapolation method |
| CN101988958A (en) * | 2009-08-07 | 2011-03-23 | 华东电力试验研究院有限公司 | Checking device and checking method of accuracy of capacitor voltage transformer |
| WO2013004042A1 (en) * | 2011-07-05 | 2013-01-10 | 国网电力科学研究院 | Method and apparatus for calibrating voltage transformer serial addition |
| CN103616652A (en) * | 2013-11-23 | 2014-03-05 | 华中科技大学 | Error measurement method, system and application for capacitive voltage divider |
| CN109425845A (en) * | 2017-09-05 | 2019-03-05 | 弗兰克公司 | The calibration system of voltage measuring apparatus |
| CN112083210A (en) * | 2020-06-15 | 2020-12-15 | 上海市计量测试技术研究院 | Analog standard shunt for measuring broadband current and measuring method thereof |
| CN113156359A (en) * | 2021-04-16 | 2021-07-23 | 中国电力科学研究院有限公司 | Method and system for determining metering error of capacitor voltage transformer |
| US12130308B2 (en) | 2019-09-23 | 2024-10-29 | 3M Innovative Properties Company | Adjustable voltage sensor |
-
2009
- 2009-08-07 CN CN2009202076029U patent/CN201477203U/en not_active Expired - Lifetime
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101988958A (en) * | 2009-08-07 | 2011-03-23 | 华东电力试验研究院有限公司 | Checking device and checking method of accuracy of capacitor voltage transformer |
| CN101872007A (en) * | 2010-06-10 | 2010-10-27 | 江西省电力科学研究院 | Three-phase voltage transformer verification method based on voltage transformer load error curve extrapolation method |
| CN101872007B (en) * | 2010-06-10 | 2012-12-26 | 江西省电力科学研究院 | Calibration method of three-phase voltage transformer based on voltage transformer load error curve extrapolation |
| WO2013004042A1 (en) * | 2011-07-05 | 2013-01-10 | 国网电力科学研究院 | Method and apparatus for calibrating voltage transformer serial addition |
| CN103616652A (en) * | 2013-11-23 | 2014-03-05 | 华中科技大学 | Error measurement method, system and application for capacitive voltage divider |
| CN109425845A (en) * | 2017-09-05 | 2019-03-05 | 弗兰克公司 | The calibration system of voltage measuring apparatus |
| US12130308B2 (en) | 2019-09-23 | 2024-10-29 | 3M Innovative Properties Company | Adjustable voltage sensor |
| CN112083210A (en) * | 2020-06-15 | 2020-12-15 | 上海市计量测试技术研究院 | Analog standard shunt for measuring broadband current and measuring method thereof |
| CN112083210B (en) * | 2020-06-15 | 2023-12-05 | 上海市计量测试技术研究院 | Analog standard shunt for measuring broadband current and its measurement method |
| CN113156359A (en) * | 2021-04-16 | 2021-07-23 | 中国电力科学研究院有限公司 | Method and system for determining metering error of capacitor voltage transformer |
| CN113156359B (en) * | 2021-04-16 | 2024-01-26 | 中国电力科学研究院有限公司 | A method and system for determining measurement error of capacitive voltage transformer |
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Granted publication date: 20100519 |