CN209606602U - The detection device of generator voltage mutual inductor winding interturn short-circuit failure - Google Patents
The detection device of generator voltage mutual inductor winding interturn short-circuit failure Download PDFInfo
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- CN209606602U CN209606602U CN201920107055.0U CN201920107055U CN209606602U CN 209606602 U CN209606602 U CN 209606602U CN 201920107055 U CN201920107055 U CN 201920107055U CN 209606602 U CN209606602 U CN 209606602U
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Abstract
The utility model relates to the detection devices of generator voltage mutual inductor winding interturn short-circuit failure, technical solution is, including frequency variation signal generator, binary channels frequency variation signal measuring device and computer, the signal output end of frequency variation signal generator is connected with the one of test side of binary channels frequency variation signal measuring device, the output end of binary channels frequency variation signal measuring device is connected with the input terminal of computer, the utility model structure novel is unique, instrument and equipment is small in size, carry aspect, it is also extremely convenient from wiring in equipment first winding when test, the shorted-turn fault of PT at the exits of generators winding can be effectively detected out at the scene, in the short-circuit low-down situation of circle accounting still can accurate detection go out short trouble, measurement sensitivity is high, accuracy is high, using this technology, it can be easy, effectively, intuitively detect generator PT winding interturn short-circuit failure is exported, it can recessive defect inside discovering device early.
Description
Technical field
The utility model relates to power industry generator outlet side voltage transformer (abbreviation PT at the exits of generators) winding turns
Between short trouble test, especially with frequency variation signal occur and measure analytical technology carry out PT at the exits of generators winding inter-turn
The detection device of short trouble.
Background technique
Generator outlet side voltage transformer plays measurement generator outlet voltage, metering outlet electricity and provides relay and protects
The shield important function of voltage signal, once breaking down, the safe and stable operation that will seriously affect unit even results in unit
Unplanned outage.In recent years, the electricity power enterprise of power industry repeatedly occurs to lack because PT at the exits of generators winding interturn short-circuit insulate
Generator unplanned outage event caused by falling into, and still lack convenient, effective, sensitivity highland detection power generation at the scene at present
The method and apparatus of machine outlet PT winding interturn short-circuit failure.
In current on-the-spot test, mainly have three for the detection method of PT at the exits of generators winding interturn short-circuit failure
Kind, be D.C. resistance method of testing, no-load voltage ratio method of testing and no-load current method of testing respectively, above-mentioned three kinds of methods be primarily present it is following not
Foot:
1) DC resistance method detection sensitivity is relatively low.The voltage class of PT at the exits of generators first winding is according to unit capacity
Difference have different, mainly within the scope of 15-27kV, the number of turns of first winding is mostly more than 10000 circles.Once around
The initial stage that group shorted-turn fault occurs may only short-circuit a few circles to tens circles, D.C. resistance in this case change
Rate very little, by taking short-circuit 30 circles as an example, D.C. resistance change rate is no more than 3/1000ths, and the change rate of this degree is less than direct current
The normal permission test error range of resistance test instrument, thus shorted-turn fault is difficult to be found and confirm.Only work as circle
Between short trouble sustainable development to more serious follow-up phase, D.C. resistance change rate be more than 2 percent or 3 percent with
When upper, it could confirm that there are failures for equipment by the test.
2) no-load voltage ratio method of testing detection sensitivity is low.It is similar with DC resistance method test, when the short circuit of shorted-turn fault
When the number of turns only has several circles to tens circle, the result of no-load voltage ratio test is equally varied less, and is not more than 3/1000ths substantially, is less than
The normal permission test error of no-load voltage ratio tester device, thus also can not effectively find and confirm the shorted-turn fault of equipment.
3) no-load current test can the more delicately shorted-turn fault of discovering device.Inside PT at the exits of generators
There are when the shorted-turn fault of several circles to tens circles, when being tested using no-load current method, be applied to equipment some it is secondary around
No-load current in group can significantly increase, and compare history no-load current data, so that it may the turn-to-turn short circuit of discovery and confirmation equipment
Failure.But since instrument needed for no-load current test is inconvenient to carry, after equipment installation is in place in the small space in PT cabinet
Many reasons such as wiring is more difficult from secondary winding, and device history data is sometimes incomplete, this method at the scene also compared with
It is few to use.
Utility model content
For above situation, for the deficiency for overcoming the prior art, the purpose of the utility model is just to provide a kind of generator
The detection device of voltage transformer winding interturn short-circuit failure, can effectively solve that on-the-spot test sensitivity is low, accuracy is low
Problem.
The technical solution that the utility model solves is:
A kind of detection device of generator voltage mutual inductor winding interturn short-circuit failure, including it is frequency variation signal generator, double
Channel frequency variation signal measuring device and computer, in which:
Frequency variation signal generator: for output frequency continuously adjustable variation sine wave AC voltage signal, as to
Survey the signal source of generator outlet side voltage transformer winding；
Binary channels frequency variation signal measuring device: for measuring testing generator outlet side electricity under different frequency signals source simultaneously
Press the signal voltage of mutual inductor winding signal input terminal and output end；
Computer: for passing through the signal voltage acquired under binary channels frequency variation signal measuring device different frequency signals source
Formula K (f)=20lg (Vo/Vi) output characteristic curve, in formula, f is frequency；Vi is that testing generator outlet side voltage is mutual
Sensor winding head end applied signal voltage；Vo is testing generator outlet side voltage transformer winding ends output signal voltage；
The characteristic curve as generator outlet side voltage transformer winding inter-turn whether the judgement benchmark of short trouble；
K (f) is the performance data under a frequency f,, will using characteristic data value as ordinate using frequency values as abscissa
Corresponding performance data is depicted as continuous curve under all frequencies, which is testing generator outlet side voltage transformer
The characteristic curve of winding；
The signal output end of the frequency variation signal generator and the one of test side of binary channels frequency variation signal measuring device
It is connected, as the signal input part of testing generator outlet side voltage transformer winding, binary channels frequency variation signal measuring device
Signal output end of another test side as testing generator outlet side voltage transformer winding, the measurement of binary channels frequency variation signal
The output end of device is connected with the input terminal of computer.
The utility model structure novel is unique, and instrument and equipment is small in size, carries aspect, when test from equipment first winding
Wiring is also extremely convenient, and the shorted-turn fault of PT at the exits of generators winding can be effectively detected out at the scene, in short-circuit circle
In the low-down situation of accounting still can accurate detection go out short trouble, measurement sensitivity is high, and accuracy is high, using this skill
Art, can it is easy, effectively, intuitively detect PT at the exits of generators winding interturn short-circuit failure, can be early inside discovering device
Recessive defect, generator unplanned outage thing caused by preventing because of PT at the exits of generators winding interturn short-circuit insulation defect
Part has good Social benefit and economic benefit.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of the utility model detection device.
Fig. 2 is PT at the exits of generators winding equivalent structure figure.
Fig. 3 is PT at the exits of generators winding equivalent network figure.
Fig. 4 is the actually detected characteristic curve comparison diagram of the utility model detection method.
Specific embodiment
Specific embodiment of the present utility model is described in further detail with reference to embodiments.
A kind of detection device of generator voltage mutual inductor winding interturn short-circuit failure of the utility model, including frequency variation signal
Generator, binary channels frequency variation signal measuring device and computer, in which:
Frequency variation signal generator: for output frequency continuously adjustable variation sine wave AC voltage signal, as to
Survey the signal source of generator outlet side voltage transformer winding；
Binary channels frequency variation signal measuring device: for measuring testing generator outlet side electricity under different frequency signals source simultaneously
Press the signal voltage of mutual inductor winding signal input terminal and output end；
Computer: for passing through the signal voltage acquired under binary channels frequency variation signal measuring device different frequency signals source
Formula K (f)=20lg (Vo/Vi) output characteristic curve, in formula, f is frequency；Vi is that testing generator outlet side voltage is mutual
Sensor winding head end applied signal voltage；Vo is testing generator outlet side voltage transformer winding ends output signal voltage；
The characteristic curve as generator outlet side voltage transformer winding inter-turn whether the judgement benchmark of short trouble；
K (f) is the performance data under a frequency f,, will using characteristic data value as ordinate using frequency values as abscissa
Corresponding performance data is depicted as continuous curve under all frequencies, which is testing generator outlet side voltage transformer
The characteristic curve of winding；
The signal output end of the frequency variation signal generator and the one of test side of binary channels frequency variation signal measuring device
It is connected, as the signal input part of testing generator outlet side voltage transformer winding, binary channels frequency variation signal measuring device
Signal output end of another test side as testing generator outlet side voltage transformer winding, the measurement of binary channels frequency variation signal
The output end of device is connected with the input terminal of computer.
The output end of signal input part, signal output end and binary channels frequency variation signal measuring device can connect terminals
Son facilitates wiring.
When detection, the frequency variation signal generator signal output end and binary channels frequency variation signal measuring device one of them
The total end of test side is connected with the head end of testing generator outlet side voltage transformer winding, binary channels frequency variation signal measuring device
Another test side be connected with the end of testing generator outlet side voltage transformer winding.
The frequency variation signal generator is function signal generator.
The binary channels frequency variation signal measuring device is dual channel oscilloscope.
The power input of the frequency variation signal generator is connected with computer, with computer utility power supply.
A kind of generator outlet side voltage transformer winding interturn short-circuit fault detection method of above-mentioned detection device, including
Following steps:
One, confirm testing generator exit potential mutual inductor state
Testing generator exit potential mutual inductor should be at the power failure of inoperative, the first winding of voltage transformer
Insurance has been removed, it is ensured that voltage transformer and other equipment rooms that may be charged have apparent physics cut-off point；
Two, confirmation device frequency variation signal occurs and measurement functional status is normal
The signal input part of the detection device and signal output end are shorted, lower-frequency limit, the frequency of frequency variation signal are set
The rate upper limit and the step-length of frequency variation, then starter carries out frequency variation signal generation and measures the self-checking of function, calculates
The characteristic curve of machine output, which should be, to be remained unchanged and the not no horizontal linear of attenuation；
Three, data acquire
PT at the exits of generators is a kind of electromagnetic potential transformer, is a kind of low capacity, small size, big electricity from structure
The step-down transformer of pressure ratio, basic principle is identical as transformer, by first winding, secondary winding, iron core, lead-out wire and absolutely
Edge structure etc. is constituted.Its winding wire diameter is very thin, the number of turns is more than 10000 circles, is divided into tens of layer arrangements and surrounds annular iron
On core, the inductance under D.C. resistance and power frequency is very big, and D.C. resistance is usually up to hundreds of ohms, and frequency inductance is up to number
Hundred is prosperous, and equivalent structure figure is as shown in Figure 2.
According to PT at the exits of generators winding equivalent structure figure, with reference to the equivalent circuit diagram of transformer equipment in typical circuit,
It can equivalent to regard the passive linear that one is made of inductance, resistance and capacitor equal distribution parameter as double by PT at the exits of generators winding
Port network, it is assumed that inductance, resistance and the capacitor of winding certain length are respectively L, R and C, the equivalent network of winding such as Fig. 3
It is shown；
The sinusoidal AC voltage signal of variation can be continuously adjusted by applying frequency from the head end of winding, while being measured and being recorded
It is input to the signal voltage of winding head end and is transmitted to the output signal voltage of winding tail end, input letter using the head end of record
Number voltage and end output signal voltage pass through the series of characteristics function (characteristic under the corresponding different frequency that calculates that you can get it
Data):
K (f)=20lg (Vo/Vi)
F-frequency
Vi-head end applied signal voltage
Vo-end output signal voltage
It will be connected by measurement, a series of and frequency dependence the characterisitic function values being calculated with smoothed curve,
The characteristic curve of the PT at the exits of generators winding in particular frequency range can be obtained.
The signal input part of the detection device is connected to testing generator outlet side voltage transformer one by lead
The signal output end of the detection device is connected to testing generator outlet side mutual induction of voltage by lead by the head end of secondary winding
The end of device first winding, starter carry out the generation and measurement of frequency variation signal, and computer passes through public affairs under each frequency
Formula K (f)=20lg (Vo/Vi) records each and corresponds to measuring signal treated performance data K (f), with frequency values for horizontal seat
Mark, using characteristic data value as ordinate, is depicted as continuous curve for performance data corresponding under all frequencies, which is
The characteristic curve of testing generator outlet side voltage transformer winding；
When there is no when turn-to-turn short circuit, the inductance of winding, resistance, capacitor equal distribution parameter are for PT at the exits of generators winding
It is fixed, the network that they are formed be also it is fixed, frequency variation signal characteristic curve be it is fixed, when winding exist it is different degrees of
Shorted-turn fault when, inductance, resistance, capacitor equal distribution parameter can change, and the parameters such as induction reactance, capacitive reactance can become with frequency
To change and varies widely, resistance parameter then varies less, and then the parameter of the equivalent network of PT equipment will change, this
When frequency conversion characteristics of signals curve compared with previous characteristic curve will generate difference even notable difference, thus realize to generator
Export the judgement of PT winding interturn short-circuit failure.
Four, data processing
The characteristic curve result of generator outlet side voltage transformer winding to be measured is analyzed:
A, it when tested voltage transformer has previous historical characteristics curve, by the characteristic curve of this acquisition and goes through
The comparison of history characteristic curve when characteristic curve changes, that is, can determine whether the turn-to-turn short circuit of winding occur inside voltage transformer
Defect, the characteristic curve, which changes, has notable difference for characteristic wave crest, the quantity of trough, position or amplitude；
B, when tested voltage transformer is without previous historical characteristics curve, confirm generator outlet voltage transformer
A, B, C three-phase equipment whether be same model parameter, identical manufactory equipment, if it is (overwhelming majority is), then phase
Characteristic curve with model parameter, the voltage transformer equipment room of identical manufactory is closely similar or similar, thus can be with
It is mutually compared using the characteristic curve of three-phase equipment, if the characteristic curve of the equipment room mutually compared at this time changes
When, it also may determine that the turn-to-turn short circuit defect that winding has occurred inside voltage transformer；The characteristic curve change for
Characteristic wave crest, the quantity of trough, position or amplitude have notable difference；
Five, to judging inside voltage transformer to carry out duplicate measurements there are the equipment of winding interturn short-circuit defect, confirmation is surveyed
There is no abnormal for examination process and test result.
The characteristic curve change specially comparison after this acquire characteristic curve compared to historical characteristics song
Line wave crest, trough quantity increase by 1 or more or the corresponding frequency location generation of wave crest, trough is more than the change of 100Hz, or
The variation of 15dB or more occurs for the corresponding amplitude of wave crest, trough；Or the combination of the above three.
The utility model technology achieves good effect through practical application, and concrete condition is as follows:
Using the HR 1000F type tester of Datang Central China electric power experiment al research institute development, respectively and using D.C. resistance
The conventional testing techniques such as method, no-load voltage ratio method of testing compare test, verify the feasibility and reliability of context of methods:
(1) for test product using JDZX9-20F1 generator outlet PT as test item, test product winding total number of turns is about 13000
Circle compares test in the case where winding is without turn-to-turn short circuit and artificial manufacture turn-to-turn short circuit respectively, wherein manually manufacture circle
Between short circuit when be divided into short-circuit 5 circles, short-circuit 35 circles, the different operating conditions of 3 kinds of short-circuit 96 circle.
(2) press traditional test method, first with wheatstone bridge, no-load voltage ratio tester respectively no turn-to-turn short circuit, 3 kinds not
Amount to degree turn-to-turn short circuit and compare test under 4 kinds of operating conditions, test result is shown in Table 1.
(3) secondly, also carrying out the test under same 4 kinds of operating conditions to test item using HR 1000F type tester.
(4) finally, the spirit of PT equipment winding interturn short-circuit failure is analyzed under different operating conditions and judged to comparison several method
Quick property and validity.
1 DC resistance method of table and no-load voltage ratio the method for testing test result under four kinds of operating conditions compare
It can be seen that when being tested with traditional DC resistance method, in short-circuit 5 circle of the number of turns and short-circuit 35 circle, direct current
Resistive rate is very small, and respectively 4/10000ths and 3/1000ths or so, shorted-turn fault can not be judged whether there is.When short
When road the number of turns reaches 96 circle, D.C. resistance change rate only conscientiously carries out data analysis, Cai Youke just close to 1 percent at this time
Can it will be noted that data situation of change, suspect test product there may be shorted-turn faults.
When with traditional no-load voltage ratio method test, even if short-circuit the number of turns reaches 96 circle, no-load voltage ratio data variation is also only thousand points
Two or so, can not judge carry out accurate failure there are shorted-turn fault or instrument test error and sentence at all
It is disconnected.
And use the utility model proposes frequency variation signal occur and measurement analytical technology test when, test result such as Fig. 4
It is shown, in which: curve 1:PT normal condition；Short-circuit 5 circles of curve 2:PT；Short-circuit 35 circles of curve 3:PT；Curve 4:PT short circuit 96
Circle.
As seen from the figure, under 3 kinds of different degrees of turn-to-turn short circuit operating conditions, corresponding characteristic curve and the normal nothing of PT equipment
There is obviously difference in characteristic curve when turn-to-turn short circuit.Even if in the case where only short-circuit 5 circle, characteristic change
Change also very intuitive and obvious, the variation of trough amplitude is more than 15dB, in 96 circle of short circuit, wave crest, trough position and
Significant change has occurred in amplitude, can explicitly judge very much that there are shorted-turn faults for equipment.As it can be seen that using this technology, it can
With it is easy, effectively, intuitively detect PT at the exits of generators winding interturn short-circuit failure, recessive inside discovering device early can lack
It falls into, generator unplanned outage event caused by preventing because of PT at the exits of generators winding interturn short-circuit insulation defect, tool
There is good Social benefit and economic benefit.
Claims (4)
1. a kind of detection device of generator voltage mutual inductor winding interturn short-circuit failure, which is characterized in that including frequency variation signal
Generator, binary channels frequency variation signal measuring device and computer, in which:
Frequency variation signal generator: for the sine wave AC voltage signal of output frequency continuously adjustable variation, as hair to be measured
The signal source of motor outlet side voltage transformer winding；
Binary channels frequency variation signal measuring device: mutual for measuring testing generator outlet side voltage under different frequency signals source simultaneously
The signal voltage of sensor winding signal input terminal and output end；
Computer: for the signal voltage acquired under binary channels frequency variation signal measuring device different frequency signals source to be passed through formula
K (f)=20lg (Vo/Vi) output characteristic curve, in formula, f is frequency；Vi be testing generator outlet side voltage transformer around
Group head end applied signal voltage；Vo is testing generator outlet side voltage transformer winding ends output signal voltage；The characteristic
Curve as generator outlet side voltage transformer winding inter-turn whether the judgement benchmark of short trouble；
The signal output end of the frequency variation signal generator is connected with the one of test side of binary channels frequency variation signal measuring device,
As the signal input part of testing generator outlet side voltage transformer winding, binary channels frequency variation signal measuring device another
Signal output end of the test side as testing generator outlet side voltage transformer winding, binary channels frequency variation signal measuring device
Output end is connected with the input terminal of computer.
2. the detection device of generator voltage mutual inductor winding interturn short-circuit failure according to claim 1, feature exist
In the frequency variation signal generator signal output end is public with the one of test side of binary channels frequency variation signal measuring device
End is connected with the head end of testing generator outlet side voltage transformer winding, another inspection of binary channels frequency variation signal measuring device
End is surveyed to be connected with the end of testing generator outlet side voltage transformer winding.
3. the detection device of generator voltage mutual inductor winding interturn short-circuit failure according to claim 1, feature exist
In the frequency variation signal generator is function signal generator.
4. the detection device of generator voltage mutual inductor winding interturn short-circuit failure according to claim 1, feature exist
In the binary channels frequency variation signal measuring device is dual channel oscilloscope.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109521391A (en) * | 2019-01-23 | 2019-03-26 | 中国大唐集团科学技术研究院有限公司华中电力试验研究院 | The detection device and method of generator voltage mutual inductor winding interturn short-circuit failure |
-
2019
- 2019-01-23 CN CN201920107055.0U patent/CN209606602U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109521391A (en) * | 2019-01-23 | 2019-03-26 | 中国大唐集团科学技术研究院有限公司华中电力试验研究院 | The detection device and method of generator voltage mutual inductor winding interturn short-circuit failure |
| CN109521391B (en) * | 2019-01-23 | 2024-02-09 | 中国大唐集团科学技术研究院有限公司华中电力试验研究院 | Device and method for detecting turn-to-turn short circuit fault of generator voltage transformer winding |
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