CN102305919B - Calibration device and method capable of synchronously measuring multiple voltage transformers at one time - Google Patents

Abstract

The invention discloses a calibration device and a calibration method capable of synchronously measuring multiple voltage transformers at one time, and belongs to the technical field of metering tests of electric power. In order to solve the problems that the efficiency of measurement is extremely low, an operator frequently contacts high voltage and the safety of production is reduced because the conventional voltage transformer can only be independently measured, a method for combining a plurality of calibrated voltage transformers with a high-standard voltage transformer to form a comparison method circuit is used in the invention; a multi-channel transformer calibrator is used for directly acquiring a differential voltage signal between the plurality of calibrated voltage transformers and the high-standard voltage transformer; and the multiple voltage transformers can be synchronously measured at one time by calculation. By the calibration device, the working efficiency of measuring the voltage transformers by the operator is improved, and the high-voltage contacting frequency of the operator is reduced, so that more safe measurement is ensured. Therefore, the calibration device and the calibration method are major breakthrough in a voltage transformer calibration technology.

Description

Calibration equipment and the method for many voltage transformer (VT) of one subsynchronous survey

Technical field

The present invention relates to a kind ofly with many voltage transformer devices of pacing, also relate to the method for calibration of many voltage transformer (VT) of a subsynchronous survey, belong to the electric-power metering technical field of measurement and test.

Background technology

A large amount of voltage transformer (VT) will be produced and use to the power high voltage metering field all every year, the verification wiring of voltage transformer (VT) is complicated and relate to height and be pressed with certain danger, the voltage transformer (VT) calibration equipment be for detection of with the exact instrument of measuring transformer error, being again one of visual plant of enhancing productivity and keeping the safety in production, is also one of indispensable important support equipment of development electric utility.

The conventional voltage transformer calibrating device is comprised of stepup transformer, normal voltage mutual inductance, voltage load box, mutual-inductor tester, regulator, tested mutual induction of voltage six parts, the wiring of conventional voltage ct calibrating as shown in Figure 1, by controlling manually or automatically regulator, then according to a plurality of test points of setting that stipulate in rules or artificial, one-point measurement one by one, accompanying drawing 2 is existing many voltage measuring transformer process flow diagrams.Completing the calibrating of voltage transformer (VT) probably needs 10-15 minute, and often completing one just needs rewiring, inefficiency, and also wiring relates to high pressure and has certain danger.Along with the continuous increase-volume enlarging of electric system, a large amount of voltage transformer (VT) need to be completed verifying work, in the situation that the reviewer can not significantly promote, needs to improve in a hurry the efficient of verifying work; And voltage transformer (VT) verification wiring relates to high pressure and has certain danger, reduces the frequency that operating personnel contact high pressure, can make voltage transformer (VT) verification operation personnel work safer.

Summary of the invention

Fundamental purpose of the present invention is that efficient, the safe pick-up unit of many voltage transformer (VT) of an a kind of synchro measure is provided for the voltage transformer (VT) verification, its wiring is simple and safe reliable, after once fixing a point, can complete the measurement of the specified and lower limited load of many voltage transformer (VT), work efficiency and safety all are significantly improved, and the present invention also provides the method for calibration of many voltage transformer (VT) of a synchro measure.

in order to achieve the above object, the invention provides calibration equipment and the method for calibration thereof of many voltage transformer (VT) of a kind of one subsynchronous survey, by selecting the electric pressure of tested voltage transformer (VT), the switchgear of hyperchannel mutual-inductor tester automatic switchover standard potential transformer makes standard potential transformer have identical no-load voltage ratio with tested voltage transformer (VT), with N only tested voltage transformer (VT) and standard potential transformer be connected into the relative method circuit, be high-end error of measurement circuit as Fig. 3, Fig. 4 is low side error of measurement circuit, by the control of hyperchannel mutual-inductor tester switching devices, make tested voltage transformer secondary side load different dummy loads, obtain the tested voltage transformer (VT) differential pressure signal in N road and standard potential transformer canonical reference signal under different dummy loads, by the tested voltage transformer (VT) differential pressure signal in N road under different dummy loads and standard potential transformer canonical reference signal are carried out signal condition, carry out synchronized sampling by Multi-path synchronous A/D, digital signal processor (DSP) carries out the fundamental voltage amplitude that multiple signals fast fourier algorithm (FFT) obtains every road differential pressure signal under different dummy loads, the angle of canonical reference signal fundamental voltage amplitude and canonical reference signal and every road differential pressure signal, just can be obtained the ratio difference of every tested voltage transformer (VT) under different load by the voltage transformer error definition, the angular difference value, adopt transformer with multiple secondary load windings dummy load algorithmic formula to calculate, the disposable ratio difference of N voltage transformer (VT) under specified and lower limited load that obtain, the angular difference value.

Technical scheme of the present invention is: the calibration equipment of many voltage transformer (VT) of a kind of one subsynchronous survey comprises hyperchannel mutual-inductor tester, program control voltage-regulating system, stepup transformer, standard potential transformer, tested mutual inductor, switchgear and artificial load; Wherein program control voltage-regulating system is used for controlling booster voltage, is connected with stepup transformer two input ends; It is characterized in that: standard potential transformer and described N only tested voltage transformer (VT) are connected with stepup transformer two output terminals after connecting into the relative method circuit, described hyperchannel mutual-inductor tester control signal is connected with switchgear with the program control voltage-regulating system of control, and described hyperchannel mutual-inductor tester data acquisition mouth directly is connected with standard potential transformer canonical reference signal with the tested voltage transformer (VT) differential pressure signal in N road; N is more than or equal to 2.Its useful technique effect is: make the wiring of voltage transformer (VT) simple and safe reliable, after disposable wiring, can complete the verifying work of many voltage transformer (VT), work efficiency and safety all are significantly improved.

The calibration equipment of many voltage transformer (VT) of as above one subsynchronous survey, it is characterized in that: described artificial load is comprised of the power resistor of different resistances.Its useful technique effect is: can disposablely complete the measurement of the specified and lower limited load of many voltage transformer (VT), improve the efficient of voltage transformer (VT) verifying work.

The calibration equipment of many voltage transformer (VT) of as above one subsynchronous survey is characterized in that: described relative method circuit is high-end error of measurement circuit.Its useful technique effect is: make calibration equipment ground connection, thereby make verifying work safer.

The calibration equipment of many voltage transformer (VT) of a subsynchronous survey as described is characterized in that: described relative method circuit is low side error of measurement circuit.Its useful technique effect is: can by to multichannel low side differential pressure signal synchro measure, record the error of every tested voltage transformer (VT).

The calibration equipment of many voltage transformer (VT) of as above one subsynchronous survey is characterized in that: described switchgear is relay.Its useful technique effect is: can pass through hyperchannel mutual-inductor tester pilot relay automatic switchover dummy load.

The calibration equipment of many voltage transformer (VT) of as above one subsynchronous survey, it is characterized in that: dummy load is multiple secondary winding, and dummy load is switched winding by switchgear.Its useful technique effect is: can adapt to the tested voltage transformer (VT) verification of many specifications.

In order to improve the operability of service system, this hyperchannel mutual-inductor tester can also add the communication program with PC, realizes that the PC management software directly uploads the download checking parameter.

In order to realize the purpose of many voltage transformer (VT) of a synchro measure, the present invention also provides the method for calibration of many voltage transformer (VT) of a kind of one subsynchronous survey, and the concrete implementation step of the method is:

Step 1: set tested voltage transformer (VT) basic parameter by the PC management software;

Step 2:PC machine management software passes tested voltage transformer (VT) basic parameter and decoding under the hyperchannel mutual-inductor tester;

Step 3: by hyperchannel mutual-inductor tester gauge tap equipment, make standard potential transformer have identical no-load voltage ratio with tested voltage transformer (VT);

Step 4: control program control voltage-regulating system by the hyperchannel mutual-inductor tester stepup transformer is boosted;

Step 5: boost to rules regulation or artificial first point of setting;

Step 6: switch to voltage transformer secondary loading dummy load by hyperchannel mutual-inductor tester gauge tap;

Step 7: measure ratio, the angular difference of N voltage transformer (VT) under different dummy loads by hyperchannel mutual-inductor tester synchronized sampling;

Step 8: calculate respectively ratio, angular difference value under the specified of N voltage transformer (VT) and lower limited load by the ratio that records under different dummy loads, angular difference value by voltage transformer (VT) dummy load formula, upload to simultaneously the PC management software;

Step 9: judge whether to test all points, if do not have, boost to rules regulation or artificial set more lower, carry out above-mentioned steps 6, otherwise carry out following step 10;

Step 10: stepup transformer returns zero;

Step 11: finish;

Wherein, N is more than or equal to 2.

Compared with prior art beneficial effect of the present invention is: ratio, angular difference value under the specified and lower limited load of N voltage transformer (VT) of the subsynchronous measurement of each measurement point homogeneous of this check system, improved the work efficiency that voltage transformer (VT) detects; The disposable wiring work of completing many voltage transformer (VT) has reduced the frequency that operating personnel contact with hi-line, makes voltage transformer (VT) verification operation personnel work safer.

Description of drawings

Fig. 1 is that prior art is measured the external connection schematic diagram;

Fig. 2 is existing many voltage measuring transformer process flow diagrams

Fig. 3 is external connection schematic diagram A of the present invention;

Fig. 4 is external connection schematic diagram B of the present invention;

Fig. 5 is hyperchannel mutual-inductor tester theory diagram of the present invention;

Fig. 6 is signal conditioning circuit block diagram of the present invention;

Fig. 7 is the measurement procedure figure of many voltage transformer (VT) of the subsynchronous survey of the present invention one;

Fig. 8 is the two load winding voltage mutual inductor dummy load control chart A of secondary;

Fig. 9 is the two load winding voltage mutual inductor dummy load control chart B of secondary;

Figure 10 is the two load winding voltage mutual inductor dummy load control chart C of secondary.

Embodiment

The explanation of mark in figure: analog signal conditioner device 1, multipath A/D converter 2, dsp controller 3, steering logic and decoding 4, external storage 5, button 6, dummy load 7, LCD liquid crystal display 8, digital to analog converter DAC 9, voltage-regulating system 10, communication interface 11.

Below in conjunction with accompanying drawing, technical characterictic and the advantage above-mentioned and other to the present invention are described in more detail.

The calibration equipment of many voltage transformer (VT) of one subsynchronous survey of the present embodiment comprises hyperchannel mutual-inductor tester, program control voltage-regulating system, stepup transformer, standard potential transformer, tested mutual inductor, switchgear and dummy load; Wherein program control voltage-regulating system is used for controlling booster voltage, is connected with stepup transformer two input ends;

It is characterized in that: standard potential transformer and described N only tested voltage transformer (VT) are connected with stepup transformer two output terminals after connecting into the relative method circuit, described hyperchannel mutual-inductor tester control signal is connected with switchgear with the program control voltage-regulating system of control, and described hyperchannel mutual-inductor tester data acquisition mouth directly is connected with standard potential transformer canonical reference signal with the tested voltage transformer (VT) differential pressure signal in N road; N is more than or equal to 2.

A plurality of analog signal conditioner devices 1 of hyperchannel mutual-inductor tester be connected with many tested voltage transformer (VT) with standard potential transformer; Standard potential transformer and every tested voltage transformer (VT) are all put a dummy load in the side; The pressure regulation signal end of hyperchannel mutual-inductor tester is connected with program control voltage-regulating system.

In the present embodiment, dummy load is multiple secondary winding, and dummy load is switched winding by switchgear.Can adapt to the tested voltage transformer (VT) verification of many specifications.

The external connection schematic diagram that accompanying drawing 3 and accompanying drawing 4 are measured for the present invention, it comprises stepup transformer, standard potential transformer, N only tested voltage transformer (VT), hyperchannel mutual-inductor tester, dummy load, program control voltage-regulating system, switchgear.The present invention is by setting the primary voltage grade, and the switchgear of system's automatic switchover standard potential transformer is to corresponding no-load voltage ratio; Many tested voltage transformer (VT) and high standard voltage transformer (VT) are connected into relative method circuit such as high-end error of measurement wiring diagram 3 or low side error of measurement wiring diagram 4, obtain the multichannel differential pressure signal, by to multichannel differential pressure signal synchro measure, can obtain the error of every tested voltage transformer (VT).

Accompanying drawing 5 is the physical circuit block diagram of hyperchannel mutual-inductor tester of the present invention, is comprised of analog signal conditioner device 1, analog to digital converter 2, dsp controller 3, steering logic and decoding 4, external storage 5, button 6, dummy load 7, LCD liquid crystal display 8, digital to analog converter DAC 9, communication interface 11.after wherein analog signal conditioner device 1 receives the error signal and canonical reference signal of tested voltage transformer (VT), amplify through the homophase in modulate circuit Fig. 6, once program control amplification, every directly, Butterworth filter, the program control amplification of secondary, every directly, three program control amplifications, Butterworth filter, signal is followed and is outputed to modulus parallel operation ADC 2, outputs to dsp controller 3 through the digital signal after analog to digital conversion and carries out algorithm process, obtains dial gauge and the ratio of tested mutual inductor under different dummy loads of canonical reference signal, the angular difference value, contrast through the test point with program setting again, if do not arrive the test point of setting, control voltage-regulating system to digital to analog converter DAC 9 and boost by outputing to corresponding digital signal, until after arriving set point with reference to dial gauge, dsp controller 3 is with the ratio that calculates simultaneously under the specified and lower limited load of N voltage transformer (VT), the angular difference value, then, dsp controller 3 is with ratio, the angular difference value outputs to LCD liquid crystal display 8, communication interface (11) and external storage 5 storages.

Accompanying drawing 7 is once surveyed the measurement procedure figure of many voltage transformer (VT) methods of calibration for the present invention, the invention provides a kind of method of calibration with many voltage transformer (VT) of pacing, and the method realizes by following steps:

Step 1: set tested voltage transformer (VT) basic parameter by the PC management software;

Step 2:PC machine management software passes tested voltage transformer (VT) basic parameter and decoding under the hyperchannel mutual-inductor tester;

Step 3: by hyperchannel mutual-inductor tester gauge tap equipment, make standard potential transformer have identical no-load voltage ratio with tested voltage transformer (VT);

Step 4: control program control voltage-regulating system by the hyperchannel mutual-inductor tester stepup transformer is boosted;

Step 5: boost to rules regulation or artificial first point of setting;

Step 6: switch to voltage transformer secondary loading dummy load by hyperchannel mutual-inductor tester gauge tap;

Step 7: measure ratio, the angular difference of N voltage transformer (VT) under different dummy loads by hyperchannel mutual-inductor tester synchronized sampling;

Step 8: calculate respectively ratio, angular difference value under the specified of N voltage transformer (VT) and lower limited load by the ratio that records under different dummy loads, angular difference value by voltage transformer (VT) dummy load formula, upload to simultaneously the PC management software;

Step 9: judge whether to test all points, if do not have, boost to rules regulation or artificial set more lower, carry out above-mentioned steps 6, otherwise carry out following step 10;

Step 10: stepup transformer returns zero;

Step 11: finish;

Wherein, N is more than or equal to 2.

Accompanying drawing 8, accompanying drawing 9 and accompanying drawing 10 are the two load winding voltage mutual inductor dummy load control charts of secondary of the present invention, and dummy load gauge tap equipment is relay J 11, J12, and J21, J22 ..., JN1, JN2 forms; In the present invention, the dummy load reckoning realizes by following steps:

Step 1: dummy load pilot relay J11 in accompanying drawing 8, J12, J21, J22 ..., JN1, JN2 is in init state, and at this moment tested voltage transformer (VT) double winding is light condition, and recording respectively winding 1a1n error is f ₁₀, δ ₁₀..., f _NO, δ _NO

Step 2: dummy load pilot relay J11 in accompanying drawing 9, J21 ..., the JN1 action, relay J 12, J22 ..., JN2 is failure to actuate, at this moment tested voltage transformer (VT) winding 1a1n adds that respectively dummy load is S1, and winding 2a2n is unloaded, and recording respectively winding 1a1n error is f ₁₁, δ ₁₁..., f _N1, δ _N1

Step 3: dummy load pilot relay J11 in accompanying drawing 10, J21 ..., JN1 is failure to actuate, relay J 12, J22 ..., the JN2 action, at this moment tested voltage transformer (VT) winding 2a2n adds that respectively dummy load is S2, and winding 1a1n is unloaded, and recording respectively winding 1a1n error is f ₁₂, δ ₁₂..., f _N2, δ _N2

Step 4: the nominal error that calculates respectively N voltage transformer (VT) winding 1a1n by the dummy load formula is f _1N, δ _1N..., f _NN, δ _NNWith the lower limit error of winding 1a1n be f _1L, δ _1L..., f _NL, δ _NL

The two load winding voltage mutual inductor dummy load computing formula of secondary are:

$f_N=f_0-\frac{S_{1N}}{S_1}[(f_0-f_1)\cos ({\mathrm{\ψ}}_{1N}-{\mathrm{\ψ}}_1)+0.0291({\mathrm{\δ}}_0-{\mathrm{\δ}}_1)\sin ({\mathrm{\ψ}}_{1N}-{\mathrm{\ψ}}_1)]-\frac{S_{2N}}{S_2}[(f_0-f_2)\cos ({\mathrm{\ψ}}_{2N}-{\mathrm{\ψ}}_2)+0.0291({\mathrm{\δ}}_0-{\mathrm{\δ}}_2)\sin ({\mathrm{\ψ}}_{2N}-{\mathrm{\ψ}}_2)]$

${\mathrm{\δ}}_N={\mathrm{\δ}}_0-\frac{S_{1N}}{S_1}[({\mathrm{\δ}}_0-{\mathrm{\δ}}_1)\cos ({\mathrm{\ψ}}_{1N}-{\mathrm{\ψ}}_1)-34.38(f_0-f_1)\sin ({\mathrm{\ψ}}_{1N}-{\mathrm{\ψ}}_1)]-\frac{S_{2N}}{S_2}[(f_0-f_2)\cos ({\mathrm{\ψ}}_{2N}-{\mathrm{\ψ}}_2)-34.38(f_0-f_2)\sin ({\mathrm{\ψ}}_{2N}-{\mathrm{\ψ}}_2)]$

In formula: f ₀, f ₁, f ₂, f _N---be respectively winding 1a1n winding 1a1n and 2a2n be all unloaded,

1a1n is load S ₁With 2a2n be that zero load and 2a2n are load S for unloaded, 1a1n ₂, 1a1n

Be rated load S _1NWith 2a2n be rated load S _2NUnder the ratio difference, unit (%);

δ ₀, δ ₁, δ ₂, δ _N---being respectively winding 1a1n is all that zero load, 1a1n are load S at winding 1a1n and 2a2n ₁With 2a2n be that zero load and 2a2n are load S for unloaded, 1a1n ₂, 1a1n is rated load S _1NWith 2a2n be rated load S _2NUnder the angular difference value, unit (');

ψ ₁, ψ ₂, ψ _1N, ψ _2N---be respectively load S ₁, S ₂, S _1N, S _2NPower-factor angle.

Table 1 is the computation process that 0.5 grade of two load winding voltage mutual inductor of 10kV/100V load dummy load 1k Ω.Error information under contrast actual measurement rated load and dummy load calculate the error information under rated load, satisfy the requirement of electric power mutual-inductor vertification regulation fully.

The dummy load of 0.5 grade of two load winding voltage mutual inductor of table 1 10kV/100V and the contrast of actual measurement rated load error

when 80% rules ratio, the angular difference of N mutual inductor under different dummy loads of naming a person for a particular job surveyed, after calculating respectively ratio under the specified of N voltage transformer (VT) and lower limited load, angular difference value by voltage transformer (VT) dummy load formula, microprocessor is controlled second rules point that stepup transformer boosts to mutual inductor, 100% of described second rules point position mutual inductor secondary voltage ratings, at second rules point the ratio of N mutual inductor under different dummy loads, angular difference has been surveyed, and calculate respectively ratio under the specified of N voltage transformer (VT) and lower limited load by voltage transformer (VT) dummy load formula, the angular difference value, then, pointwise is boosted, until boost to mutual inductor secondary voltage ratings 120%, each above-mentioned rules point all repeats the ratio under the specified and lower limited load of the above-mentioned N of a calculating voltage transformer (VT), the angular difference value, then voltage returns zero, measure and finish.

Ratio, angular difference value under the specified and lower limited load of N voltage transformer (VT) of the subsynchronous measurement of this a kind of each measurement point homogeneous of check system with many voltage transformer (VT) of pacing make voltage transformer (VT) calibration operation efficient and production safety that significant raising arranged.

Above explanation is illustrative to the present invention, and nonrestrictive, and those of ordinary skills understand; in the situation that do not break away from the spirit and scope that following claims limit, can make modification, change; or equivalence, but all will fall within the scope of protection of the present invention.

Claims (1)

1. the method for inspection of N voltage transformer (VT) of a subsynchronous survey is characterized in that:

Step 1: set only tested voltage transformer (VT) basic parameter of N by the PC management software;

Step 2:PC machine management software passes N only tested voltage transformer (VT) basic parameter and decoding under the hyperchannel mutual-inductor tester;

Step 3: by hyperchannel mutual-inductor tester gauge tap equipment, make standard potential transformer and N only tested voltage transformer (VT) have identical no-load voltage ratio;

Step 4: control program control voltage-regulating system by the hyperchannel mutual-inductor tester stepup transformer is boosted;

Step 5: boost to rules regulation or artificial first point of setting;

Step 6: switch by hyperchannel mutual-inductor tester gauge tap equipment, to only tested voltage transformer secondary loading dummy load of N;

Step 7: measure only ratio, the angular difference of tested voltage transformer (VT) under different dummy loads of N by hyperchannel mutual-inductor tester synchronized sampling;

Step 8: by the ratio that records under different dummy loads, angular difference value, calculate respectively only ratio, the angular difference of tested voltage transformer (VT) under nominal load and lower limit load of N by voltage transformer (VT) dummy load formula, upload to simultaneously the PC management software;

Step 9: judge whether to test all points, if do not have, boost to rules regulation or artificial set more lower, carry out above-mentioned steps 6, otherwise carry out following step 10;

Step 10: stepup transformer returns zero;

Step 11: finish;

Wherein, N is more than or equal to 2.

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