CN101819264A - Portable type current transformer calibrating device - Google Patents
Portable type current transformer calibrating device Download PDFInfo
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- CN101819264A CN101819264A CN 201010172914 CN201010172914A CN101819264A CN 101819264 A CN101819264 A CN 101819264A CN 201010172914 CN201010172914 CN 201010172914 CN 201010172914 A CN201010172914 A CN 201010172914A CN 101819264 A CN101819264 A CN 101819264A
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Abstract
The invention relates to a portable type current transformer calibrating device which comprises a voltage regulator T, a no-load current transformer T1, an auxiliary current transformer T2 for artificial load, a current raiser T3, a transformer T4, an artificial load voltage transformer T5, a negative artificial load voltage transformer T6, a 1A/5A standard current transformer T7, a resistor R, an impedance Z, connecting terminals LA, LB, K1 and K2, a relay and a microcomputer type transformer checking meter HEW. In the calibrating device, a traditional method can be used to calibrate a 15-600/5,1A current transformer; and an indirect method can also be used by adopting a current transformer method and the measurement of a primary exciting current, i.e. error and ratio error compensation values are measured under 5 percent of rated current according to the traditional method so as to guarantee the measuring accuracy, then the measurement of the primary exciting current is adopted to calculate, and errors are displayed. In the process of measuring, a primary current connecting lead does not need to be disconnected, and the measurement can be finished in one step. The measurement is accurate, and both actual wire connecting and testing are also convenient.
Description
Technical field
The invention belongs to transformer calibrating device, be specifically related to a kind of portable type current transformer calibrating device.
Background technology
Traditional mutual-inductor tester all is the error of measurement formula.During current transformer, load (being provided by the current capacity case) is provided tested Current Transformer Secondary in calibrating, compares with standard current transformer with current ratio, and measuring tested current transformer by tester has error with respect to standard current transformer.
Propose several indirect methods in recent years, be used for surveying the error of on-the-spot great current mutual inductor.Wherein have: 1, voltage table method and survey the calibrating installation of admittance, survey voltage ratio by voltage table and calculate the ratio difference offset, extrapolate error under 1～120% rated current, rated load and the following limited load by surveying admittance again.2, voltage transformer (VT) method and survey the calibrating installation of admittance is surveyed the ratio difference offset under the voltage transformer (VT) state, extrapolate error under 1～120% rated current, rated load and the following limited load by surveying admittance.3, increase load method calibrating installation, under 1～20% rated current, survey error by traditional method, close by increasing secondary load increase magnetic, calculate ratio difference offset and excitation admittance, extrapolate the error under 100～120% rated current, rated load and the following limited load again.4, the calibrating installation of current transformer method and survey admittance is surveyed sum of errors ratio difference offset by classic method under 1～20% rated current, again by surveying the error under admittance reckoning 1～120% rated current, rated load and the following limited load.
Above-mentioned 4 kinds of calibrating installations, relative merits are respectively arranged: the measurement that has is accurate substantially, but use is very inconvenient, needs the turn-off current lead in test process; The use that has is very convenient, but is subject to ectocine, and measuring error is big slightly.
Summary of the invention
Technical matters to be solved by this invention is to overcome above-mentioned calibrating installation deficiency is arranged, a kind of portable type current transformer calibrating device is provided, and this device can be tested by traditional method and indirect method, and is easy to use, test process need not to disconnect primary current and connects lead, accuracy of measurement height.
Technical scheme of the present invention: a kind of portable type current transformer calibrating device, it is by pressure regulator T, no-load current mutual inductor T1, artificial load auxiliary current transformer T2, current lifting device T3, transformer T4, artificial load voltage transformer (VT) T5, negative value artificial load voltage transformer (VT) T6,1A/5A standard current transformer T7, resistance R, impedance Z, ramp LA, LB, K1, K2, relay and microcomputer type mutual-inductor tester HEW form, the input termination power frequency 220V power supply of pressure regulator T, the output low pressure end connects the Y0 end of T4, high-pressure side connects the Y2 end of T4, the Y0 end connects the winding S1 end of T3 simultaneously, the Y1 of T4 holds by the S2 that relay J s is connected T3 with the Y2 end, the secondary output winding of T3 is the punching winding, with T1, the common punching of winding of T2, the Secondary Winding of T1 has 14 taps, its common port K0 is connected to the K1 terminal by relay J s, 14 tap K1～K14 are selected and are connected to the Secondary Winding common port k0 of T2 by J1～J14, be connected to the D end of microcomputer type mutual-inductor tester HEW simultaneously by relay J s, T2 is equally by 14 tap k1～k14, equally select and be connected to an end of resistance R and link with the C2 end of the winding of T6 by relay J 1～J14, be connected to the D end of microcomputer type mutual-inductor tester HEW simultaneously by relay J s, one end of another termination impedance Z of resistance R, the Z1 that connects the winding of the C1 end of a winding of T6 and T5 simultaneously holds, the D end of the Secondary Winding D0 termination microcomputer type mutual-inductor tester HEW of T6, D1 and D2 tap are succeeded electrical equipment Ja0～Ja10 by relay J d, another of impedance Z section connects the T0 end of microcomputer type mutual-inductor tester HEW, and the Z0 that connects the winding of T5 simultaneously holds, the Secondary Winding common port A0 of T5 is connected to the Tx end of microcomputer type mutual-inductor tester HEW and is connected to the L2 end of T7 or is connected to the K2 terminal through relay J s again by relay J a, tap A0 is connected with relay J d by relay J a0,10 tap A1～A10 of T5 select and are connected to relay J d by relay J a1～Ja10, the Ku end of microcomputer type mutual-inductor tester HEW is connected to the K1 terminal by relay J s, the L1 end of T7 is connected to the K1 terminal by relay J a, the L3 end is connected to the K2 terminal, and the K2 terminal is by relay J s ground connection.
The present invention compared with prior art has following beneficial effect: the present invention is on the basis of summing up four kinds of extrapolation methods of prior art, adopt the dual-purpose current transformer calibrating device of traditional method and indirect method, the one, can examine and determine 15～600/5 with classic method, the 1A current transformer; The 2nd, available indirect method adopts the current transformer method and surveys an exciting current, promptly surveys sum of errors ratio difference offset by traditional method under 5% rated current, to guarantee its accuracy of measurement; Adopt then and survey an exciting current calculating, display error.Test process need not to disconnect primary current and connects lead, once finish, not only test accurately and also physical cabling and test all very convenient.
Description of drawings
Fig. 1 is a wiring diagram of the present invention.
Embodiment
A kind of portable type current transformer calibrating device, it is by pressure regulator T, no-load current mutual inductor T1, artificial load auxiliary current transformer T2, current lifting device T3, transformer T4, artificial load voltage transformer (VT) T5, negative value artificial load voltage transformer (VT) T6,1A/5A standard current transformer T7, resistance R, impedance Z, ramp LA, LB, K1, K2, relay and microcomputer type mutual-inductor tester HEW form, the input termination power frequency 220V power supply of pressure regulator T, the output low pressure end connects the Y0 end of T4, high-pressure side connects the Y2 end of T4, the Y0 end connects the winding S1 end of T3 simultaneously, the Y1 of T4 holds by the S2 that relay J s is connected T3 with the Y2 end, the secondary output winding of T3 is the punching winding, with T1, the common punching of winding of T2, the Secondary Winding of T1 has 14 taps, its common port K0 is connected to the K1 terminal by relay J s, 14 tap K1～K14 are selected and are connected to the Secondary Winding common port k0 of T2 by J1～J14, be connected to the D end of microcomputer type mutual-inductor tester HEW simultaneously by relay J s, T2 is equally by 14 tap k1～k14, equally select and be connected to an end of resistance R and link with the C2 end of the winding of T6 by relay J 1～J14, be connected to the D end of microcomputer type mutual-inductor tester HEW simultaneously by relay J s, one end of another termination impedance Z of resistance R, the Z1 that connects the winding of the C1 end of a winding of T6 and T5 simultaneously holds, the D end of the Secondary Winding D0 termination microcomputer type mutual-inductor tester HEW of T6, D1 and D2 tap are succeeded electrical equipment Ja0～Ja10 by relay J d, another of impedance Z section connects the T0 end of microcomputer type mutual-inductor tester HEW, and the Z0 that connects the winding of T5 simultaneously holds, the Secondary Winding common port A0 of T5 is connected to the Tx end of microcomputer type mutual-inductor tester HEW and is connected to the L2 end of T7 or is connected to the K2 terminal through relay J s again by relay J a, tap A0 is connected with relay J d by relay J a0,10 tap A1～A10 of T5 select and are connected to relay J d by relay J a1～Ja10, the Ku end of microcomputer type mutual-inductor tester HEW is connected to the K1 terminal by relay J s, the L1 end of T7 is connected to the K1 terminal by relay J a, the L3 end is connected to the K2 terminal, and the K2 terminal is by relay J s ground connection.
As shown in Figure 1, T1 is a 0.02S level punching no-load current mutual inductor, and the current ratio of punching 1 circle is 150～2000/5A, and punching 10 circles can obtain 15～2000/5A, totally 24 current ratios at most.Since adopted the no-load current mutual inductor, its accuracy height, ampere turns is low, does not have winding one time, and all punching makes the weight saving of standard mutual inductor over half.T2 is the artificial load auxiliary mutual inductor, 0.5 grade, and corresponding with standard mutual inductor, there is not winding one time, all punching yet.T3 is the punching current lifting device, does not export winding, also whole punchings, and maximum output current is 720A, capacity 500VA.T4 is a step-down transformer, when indirect method is surveyed an exciting current, is used for exporting exciting current.T5 is the artificial load voltage transformer (VT), and 0.5 grade, its output voltage is corresponding to artificial load 2.5～30VA, power factor 0.8.T6 is a negative value artificial load voltage transformer (VT), and 0.5 grade, its output voltage connects the internal resistance of lead and 1/5A standard current transformer corresponding to artificial load-0.02 Ω and-0.1 Ω in order to the secondary of offsetting tested mutual inductor.T7 is a 0.01S level 1/5A standard current transformer, and its internal resistance is just in time offset by the negative value artificial load, can not give tested mutual inductor additional secondary load, tested 15～2000/1A current transformer is converted under 15～2000/5A current transformer examines and determine.
When traditional method was examined and determine mutual inductor 15～600/5A, device provided artificial load, and working current loop ToTx and difference that secondary current and error current are imported microcomputer type current transformer calibrator HEW respectively flow back to road KD, the error of the tested mutual inductor of tester direct-reading.During calibrating 15～600/1A, between two K2 terminals of tested mutual inductor and device, external Burden box; Relay J a action, cascade 1/5A standard mutual inductor makes tested mutual inductor become 15～600/5A mutual inductor and examines and determine.
When indirect method is surveyed an exciting current, relay J s action, the current lifting device step-down, exciting current is through T1 and T2 mutual inductor, K, the input of D terminal from microcomputer type mutual-inductor tester HEW, the secondary induced potential of tested mutual inductor is by the voltage circuit of Ku and ground terminal input microcomputer type mutual-inductor tester HEW, microcomputer type mutual-inductor tester HEW surveys exciting current and the phasing degree under 5～120% rated current, rated load or the following corresponding induced potential of limited load, directly shows the error of tested mutual inductor after the microcomputer computing.Principle of operation and computing formula are as follows:
By the ratio difference of classic method under following limited load and 5% rated current is f
5And under identical secondary induced potential, record one time exciting current I
5With phasing degree β, promptly can be regarded as the offset Δ f of ratio difference:
Δf＝f
5-100I
5/I
1cos(α+β))(％) (1)
α is the angle of impedance of secondary induced potential in the formula.I
1Be primary current.
Again by an exciting current I who records
0, directly calculate and display error:
f＝100I
0/I
1(cos(α+β))+Δf(％) (2)
δ＝3440I
0/I
1(sin(α+β))(’) (3)
I in the formula
0For corresponding to primary current I
1Under exciting current.
The power factor that once connects of artificial load voltage transformer (VT) T5 is 0.8 impedance, and its secondary voltage is through the normally opened contact output of one of relay J a1～Ja10, is 0.8 artificial load as one of 2.5～30VA of 5A power factor.Connecting resistance R of negative value artificial load voltage transformer (VT) T6, its secondary is selected back output-0.02 Ω or-0.1 Ω by the transfer contact of relay J d, to offset the resistance of tested mutual inductor secondary connection lead.The secondary of artificial load voltage transformer (VT) T5 and negative value artificial load voltage transformer (VT) T6 is through the series connection of the corresponding contact of relay, and an end A0 also meets the secondary terminal K2 of tested mutual inductor through above-mentioned Ja and Js two normally closed contacts; The other end is the D terminal that the public end D0 of T6 secondary meets microcomputer type mutual-inductor tester HEW, makes the secondary voltage of artificial load voltage transformer (VT) T5 and negative value artificial load voltage transformer (VT) T6 become the artificial load of tested mutual inductor, and this is the artificial load loop.
The secondary terminal K1 of tested mutual inductor also connects the L1 terminal of 1A/5A current transformer T7 through the normally opened contact of relay J a, the L3 terminal of 1A/5A current transformer T7 connects the K2 terminal of tested mutual inductor, and the L2 terminal of 1A/5A current transformer T7 connects the Tx terminal of microcomputer type mutual-inductor tester HEW through another normally opened contact of relay J a.When Ja moved, this was that tested mutual inductor secondary is the circuit of 5A through the 1/5A standard handovers by 1A.
When adopting indirect method to detect, relay J s action.The Y2 terminal of transformer T4 connects the S2 terminal of current lifting device T3 through the normally opened contact of Js, reduces the input voltage of current lifting device T3 and the primary current of output.The secondary K1 terminal of tested mutual inductor is through the normally opened contact of the relay J s of two series connection, connect the Ku terminal of microcomputer type mutual-inductor tester HEW, the K2 terminal of secondary is connected with the ground terminal of microcomputer type mutual-inductor tester HEW through the normally opened contact ground connection of Js, i.e. the operating voltage loop of the secondary induced potential of tested mutual inductor input microcomputer type mutual-inductor tester HEW.After no-load current mutual inductor T1 and artificial load are connected with auxiliary current transformer T2 secondary, the K0 of one end no-load current mutual inductor T1 directly connects microcomputer type mutual-inductor tester K terminal, other end artificial load connects the D terminal of microcomputer type mutual-inductor tester through the normally opened contact of corresponding J1～J14 normally opened contact and Js with auxiliary current transformer T2, promptly an exciting current is at this moment used the secondary of auxiliary current transformer T2 by no-load current mutual inductor T1 and artificial load, the input validation instrument is surveyed admittance, calculates exciting current.
Claims (1)
1. portable type current transformer calibrating device, it is by pressure regulator T, no-load current mutual inductor T1, artificial load auxiliary current transformer T2, current lifting device T3, transformer T4, artificial load voltage transformer (VT) T5, negative value artificial load voltage transformer (VT) T6,1A/5A standard current transformer T7, resistance R, impedance Z, ramp LA, LB, K1, K2, relay and microcomputer type mutual-inductor tester HEW form, the input termination power frequency 220V power supply that it is characterized in that pressure regulator T, the output low pressure end connects the Y0 end of T4, high-pressure side connects the Y2 end of T4, the Y0 end connects the winding S1 end of T3 simultaneously, the Y1 of T4 holds by the S2 that relay J s is connected T3 with the Y2 end, the secondary output winding of T3 is the punching winding, with T1, the common punching of winding of T2, the Secondary Winding of T1 has 14 taps, its common port K0 is connected to the K1 terminal by relay J s, 14 tap K1～K14 are selected and are connected to the Secondary Winding common port k0 of T2 by J1～J14, be connected to the D end of microcomputer type mutual-inductor tester HEW simultaneously by relay J s, T2 is equally by 14 tap k1～k14, equally select and be connected to an end of resistance R and link with the C2 end of the winding of T6 by relay J 1～J14, be connected to the D end of microcomputer type mutual-inductor tester HEW simultaneously by relay J s, one end of another termination impedance Z of resistance R, the Z1 that connects the winding of the C1 end of a winding of T6 and T5 simultaneously holds, the D end of the Secondary Winding D0 termination microcomputer type mutual-inductor tester HEW of T6, D1 and D2 tap are succeeded electrical equipment Ja0～Ja10 by relay J d, another of impedance Z section connects the T0 end of microcomputer type mutual-inductor tester HEW, and the Z0 that connects the winding of T5 simultaneously holds, the Secondary Winding common port A0 of T5 is connected to the Tx end of microcomputer type mutual-inductor tester HEW and is connected to the L2 end of T7 or is connected to the K2 terminal through relay J s again by relay J a, tap A0 is connected with relay J d by relay J a0,10 tap A1～A10 of T5 select and are connected to relay J d by relay J a1～Ja10, the Ku end of microcomputer type transducer check HEW is connected to the K1 terminal by relay J s, the L1 end of T7 is connected to the K1 terminal by relay J a, the L3 end is connected to the K2 terminal, and the K2 terminal is by relay J s ground connection.
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| CN 201010172914 CN101819264A (en) | 2010-05-10 | 2010-05-10 | Portable type current transformer calibrating device |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102508190A (en) * | 2011-11-03 | 2012-06-20 | 四川电力科学研究院 | Method for testing error influence quantity to high-voltage three-phase current transformer from high-voltage leakage current |
| CN103777171A (en) * | 2014-01-27 | 2014-05-07 | 国家电网公司 | Testing method of exciting characteristic curve of current transformer |
| CN104569895A (en) * | 2013-10-28 | 2015-04-29 | 国家电网公司 | Calibration method of standard current transformer |
| CN105938187A (en) * | 2016-05-31 | 2016-09-14 | 河北省电力建设调整试验所 | Ultrahigh-voltage current transformer feedthrough test method |
| CN106842096A (en) * | 2017-01-22 | 2017-06-13 | 国网山东省电力公司潍坊供电公司 | Auxiliary connection device is used in high-tension current inductor batch calibrating |
| CN107037388A (en) * | 2016-12-30 | 2017-08-11 | 国网辽宁省电力有限公司电力科学研究院 | A kind of Secondary Load of Voltage Transformer improves device |
| CN108761375A (en) * | 2018-07-31 | 2018-11-06 | 山西互感器电测设备有限公司 | A kind of low-power consumption program control type current mutual inductor field detecting device |
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| CN102508190A (en) * | 2011-11-03 | 2012-06-20 | 四川电力科学研究院 | Method for testing error influence quantity to high-voltage three-phase current transformer from high-voltage leakage current |
| CN104569895A (en) * | 2013-10-28 | 2015-04-29 | 国家电网公司 | Calibration method of standard current transformer |
| CN103777171A (en) * | 2014-01-27 | 2014-05-07 | 国家电网公司 | Testing method of exciting characteristic curve of current transformer |
| CN103777171B (en) * | 2014-01-27 | 2016-03-30 | 国家电网公司 | A kind of method of testing of current transformer exciting characteristic curve |
| CN105938187A (en) * | 2016-05-31 | 2016-09-14 | 河北省电力建设调整试验所 | Ultrahigh-voltage current transformer feedthrough test method |
| CN107037388A (en) * | 2016-12-30 | 2017-08-11 | 国网辽宁省电力有限公司电力科学研究院 | A kind of Secondary Load of Voltage Transformer improves device |
| CN106842096A (en) * | 2017-01-22 | 2017-06-13 | 国网山东省电力公司潍坊供电公司 | Auxiliary connection device is used in high-tension current inductor batch calibrating |
| CN106842096B (en) * | 2017-01-22 | 2021-03-23 | 国网山东省电力公司潍坊供电公司 | Auxiliary wiring device for batch verification of high-voltage current transformers |
| CN108761375A (en) * | 2018-07-31 | 2018-11-06 | 山西互感器电测设备有限公司 | A kind of low-power consumption program control type current mutual inductor field detecting device |
| CN108761375B (en) * | 2018-07-31 | 2024-05-14 | 山西互感器电测设备有限公司 | Low-power consumption program-controlled current transformer on-site calibrating device |
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Application publication date: 20100901 |