CN108181513A - A kind of arrester Coupling Between Phases capacitance test method and system based on alien frequencies method - Google Patents
A kind of arrester Coupling Between Phases capacitance test method and system based on alien frequencies method Download PDFInfo
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- CN108181513A CN108181513A CN201810215369.2A CN201810215369A CN108181513A CN 108181513 A CN108181513 A CN 108181513A CN 201810215369 A CN201810215369 A CN 201810215369A CN 108181513 A CN108181513 A CN 108181513A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/26—Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
- G01R27/2605—Measuring capacitance
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Abstract
The present invention relates to the technical field of measurement, more particularly, to a kind of arrester Coupling Between Phases capacitance test method and system based on alien frequencies method.The present invention coordinates the jamproof frequency-selecting measuring device of high-precision strong, realizes the correct measurement of arrester Coupling Between Phases capacitance by using different-frequency measuring method.It can reach that experiment is easy, purpose of safety by the present invention, and be expected safe and simple, the solution that efficiently and accurately measures as arrester Coupling Between Phases capacitance.
Description
Technical field
The present invention relates to the technical field of measurement, more particularly, to a kind of arrester Coupling Between Phases based on alien frequencies method
Capacitance test method and system.
Background technology
The test method capacitive current compensation method of mainstream is accounted in lightning arrester live-line test at present, because of security reason, does not take PT
Secondary singal transfers that station is taken to become reference voltage, brings larger original reason error and live interphase interference and instrument etc.
Reason, it is impossible to accurately measure current in resistance property value or even the problem of erroneous judgement, fail to judge occur, affect live testing technology to keeping away
The validity of thunder device defect diagonsis.
Capacitive current compensation method is method the most ripe in principle in current lightning arrester live-line test, by taking system electric
Signal is pressed to be compensated to the capacitive part in total current as benchmark, obtain the current in resistance property of reflection arrester active loss
Component.
But three-phase lightning protector is all "-" type installation at the scene, due to Coupling Between Phases capacitance and electromagnetic interference, is made each
Phase arrester is also acted on, so as to influence to monitor in addition to being acted on by this phase voltage by Coupling Between Phases by adjacent phase voltage
As a result accuracy.
Site layout project mode brings lightning arrester live-line test the influence of interphase interference, although the instrument of existing maturation is equal
There is alternate compensation function, but effect is undesirable in practical application.Existing lightning arrester live-line test method can not obtain resistive electricity
The exact value of stream, the result of live testing do not pursue the accuracy of test data, and the validity of live testing is mainly reflected in
The lateral comparison of test data, occurring the arrester deteriorated individually can find to come out in lateral comparison, it is difficult to criticizing
Secondary property, familial defect arrester state are reflected, and are difficult to find arrester early defect.
There is also the situations of erroneous judgement for live testing, and in Practical on-site test, there is also live testings to pinpoint the problems, and
Situation without exception is tested after power failure.
At present, live testing instrument manufacturer is numerous, and test philosophy, antijamming capability are different, and the equipment quality good and the bad is not
Together, in practice usually can not usage history data carry out longitudinal comparison, the trend of arrester deterioration is difficult to from historical data
It reflects.On April 25th, 2013,500kV Shantou station 500kV Shans banyan A-wire arrester are afterwards, right because lightning stroke is broken down
The reason of DC experiment for perfecting phase arrester is tested, and as a result shows that leakage current is exceeded, confirms that resistor disc deteriorates, failure is point
Deteriorating under the accumulation impact for bearing multiple lightning stroke occurs in analysis resistor disc, accelerated deterioration, and occurs under subsequent working voltage
Thermal runaway.The arrester live testing data of nearly 3 years are transferred, find the leakage current of an arrester resistive component in 2011
It is slightly increased in test process, maximum amplification is the 3.2% of A phases.The new arrester band electrical measurement for purchasing strong antijamming capability in 2012
Test instrument, leakage current of an arrester resistive component decline to a great extent, and the maximum range of decrease is the 36.2% of A phases, and result of the test is qualified, electrification
Test result is because of different instruments, and there are certain deviations, are not effectively reflected arrester resistor disc degradation trend, most
Arrester internal flaw could not be effectively checked eventually, so that accident occurs.
Arrester test site complex environment, the problem of also bringing live high interference.Test data is easily by ring
The influence of temperature, humidity, rainfall, arrester contamination degree of surface of electric, the electromagnetic environment in border etc. causes the inaccuracy of data.
Another current problem is safety problem.Have when taking voltage transformer signal at the scene inconvenience and safety it is hidden
Suffer from：1. operations staff is needed to coordinate access voltage transformer signal, there are maloperation risks；2. it needs additionally to increase isolation dress
It puts, prevents signal in instrument from sealing in voltage transformer；3. there is short-circuit risks for voltage transformer signal.Safety, letter are not met
Just the technological development direction of lightning arrester live-line test.
Since existing lightning arrester live-line test technology is there are disadvantages mentioned above, live testing data validity is deposited at present
In deficiency.
Invention content
The present invention provides a kind of arrester based on alien frequencies method to overcome at least one defect described in the above-mentioned prior art
Coupling Between Phases capacitance test method and system, it is safe and reliable.
The technical scheme is that：A kind of arrester Coupling Between Phases capacitance test method based on alien frequencies method, feature
It is, for measuring the Coupling Between Phases capacitance of A, B phase arrester, includes the following steps：
Step 1 determines that institute's survey arrester is in power failure, and A, B phase arrester upper end is hanging, and B phase arresters lower end is straight
Ground connection, A arresters lower end is also directly grounded, and a light current current transformer is accessed on its ground wire；
Step 2, frequency variation signal source output terminal connect the low-voltage terminal of high pressure PT, and the high voltage output terminal of PT connects the upper of B phase arresters
End, the shell of PT are directly grounded；
Step 3 exports the alien frequencies voltage signal U between a 40-70Hz using variable frequency signal source, pressurizes to B phases arrester；
Step 4 measures the non-power-frequency current I and variable frequency signal source of A phase arresters using the anti-interference frequency-selecting measuring device of high-precision strong
The alien frequencies voltage signal U of output；
Step 5, the no-load voltage ratio of PT is K, and the alien frequencies signal frequency of test is f, can calculate alternate coupling of A, B phase under frequency f
Close capacitance CAB=I/2πfUK；
Step 6 can similarly measure the Coupling Between Phases capacitance of B, C phase and A, C phase arrester respectively.
Further, in the step 1, arrester is the arrester without electricity operation.
Further, in the step 1, light current current transformer is connected on the ground wire of arrester, measurement range selection
In 0~5mA.
Further, in the step 2, the voltage class of high pressure PT is determined according to the voltage class of tested arrester, high
The High voltage output voltage of PT is pressed the 50%~100% of tested arrester rated voltage.
Further, in the step 4, the frequency-selecting measuring device of the anti-interference weak current of high-precision strong uses strong anti-interference
Frequency-selecting measuring technique, greatly improve the antijamming capability of measurement and the confidence level of data.
Using the system of the arrester Coupling Between Phases capacitance test method based on alien frequencies method, wherein：Including tested
Three-phase lightning protector, variable frequency signal source, high pressure PT, light current current transformer, the anti-interference frequency-selecting measuring device of high-precision strong, alternating current 220V
Power supply, grounded screen, connecting line；
Alternating current 220V power supplys are connected to variable frequency signal source to system power supply;The output of variable frequency signal source is connected to the low pressure of high pressure PT
Terminal;The High voltage output of high pressure PT is connected to the upper end of B phase arresters, the earthing of casing of high pressure PT;A, B phases arrester upper end hangs
Sky, B phase arresters lower end are directly grounded, and A arresters lower end is also directly grounded, and a weak current mutual inductance is accessed on its ground wire
Device;The output of light current current transformer is connected to the current measurement terminal of the anti-interference frequency-selecting measuring device of high-precision strong, to the different of A phases
Frequency electric current measures, while the output of variable frequency signal source is connected to the voltage survey of the anti-interference frequency-selecting measuring device of high-precision strong
Terminal is measured, the no-load voltage ratio of high pressure PT is set in the anti-interference frequency-selecting measuring device of high-precision strong, A, B phase can be calculated automatically and taken shelter from the thunder
The Coupling Between Phases capacitance of device.
Compared with prior art, advantageous effect is：（1）It is measured, can effectively avoided existing using 40-70Hz alien frequencies methods
The Hz noise of field, and can guarantee the equivalence with power frequency.（2）Strong antijamming capability, can be in the power current of thousand times of thousand times
The vector of faint alien frequencies is accurately measured under interference.（3）Intelligence degree is high.Can automatic switching range, can preserve as a result, can lead
Go out test waveform, be very beneficial for further technology analysis.（4）System core part is CPU and software algorithm.
Description of the drawings
Fig. 1 is test method block diagram of the present invention.
Fig. 2 is measurement system diagram of the present invention.
Specific embodiment
The attached figures are only used for illustrative purposes and cannot be understood as limitating the patent；It is attached in order to more preferably illustrate the present embodiment
Scheme certain components to have omission, zoom in or out, do not represent the size of actual product；To those skilled in the art,
The omitting of some known structures and their instructions in the attached drawings are understandable.Being given for example only property of position relationship described in attached drawing
Explanation, it is impossible to be interpreted as the limitation to this patent.
Fig. 1 show a kind of arrester early defect charged test method step based on total current harmonic wave vector.To survey
For the Coupling Between Phases capacitance for measuring A, B phase arrester, the measuring method includes step, and A, B phase arrester upper end is hanging,
B phase arresters lower end is directly grounded, and A arresters lower end is also directly grounded, and a light current current transformer is accessed on its ground wire.
The low-voltage terminal of high pressure PT is connect using frequency variation signal source output terminal, the high voltage output terminal of PT connects the upper end of B phase arresters, uses
Variable frequency signal source exports the alien frequencies voltage signal between a 40-70Hz, is measured using the frequency-selecting of the anti-interference weak current of high-precision strong
It is K that device, which measures the alien frequencies leakage current I of A phase arresters and the no-load voltage ratio of alien frequencies the voltage signal U, PT of variable frequency signal source output,
The alien frequencies signal frequency of test is f, can calculate Coupling Between Phases capacitance C of A, B phase under frequency fAB=I/2πfUK.Similarly may be used
The Coupling Between Phases capacitance of B, C phase and A, C phase arrester is measured respectively.
Fig. 2 show a kind of arrester Coupling Between Phases capacitor test system based on alien frequencies method, is kept away including tested three-phase
Thunder device, variable frequency signal source, high pressure PT, light current current transformer, the anti-interference frequency-selecting measuring device of high-precision strong, alternating current 220V power supplys,
Grounded screen, connecting line.
For measuring the Coupling Between Phases capacitance of A, B phase arrester, alternating current 220V power supplys are connected to variable frequency signal source to being
System power supply;The output of variable frequency signal source is connected to the low-voltage terminal of high pressure PT;The High voltage output of high pressure PT is connected to B phase arresters
Upper end, the earthing of casing of high pressure PT;A, B phases arrester upper end is hanging, and B phase arresters lower end is directly grounded, A arresters lower end
Also it is directly grounded, and a light current current transformer is accessed on its ground wire;The output of light current current transformer is connected to high-precision strong
The current measurement terminal of anti-interference frequency-selecting measuring device, measures the non-power-frequency current of A phases, while by the defeated of variable frequency signal source
Go out to be connected to the voltage measurement terminal of the anti-interference frequency-selecting measuring device of high-precision strong, in the anti-interference frequency-selecting measuring device of high-precision strong
On set the no-load voltage ratio of high pressure PT, the Coupling Between Phases capacitance of A, B phase arrester can be calculated automatically.
The present invention is tested using alien frequencies method, since the electromagnetic environment of test site is extremely complex, particularly power frequency magnetic
Interference especially severe, the present invention in alien frequencies method tested using frequency different from power frequency but close to the signal of power frequency,
The method is come Hz noise and measured signal segregation with non-50 Hz experiment power supplies, avoids its caused measurement error, simultaneously also
It can guarantee the equivalence with power frequency.
It must be the arrester not run that has a power failure that arrester is tested in the present invention, need to be to tested arrester pressurization, it is necessary to stop
The arrester that electricity is not run could be realized.
Mutual inductor in the present invention is using light current current transformer, since the Coupling Between Phases electric current in arrester is all microampere order
, the current transformer of requirement sampling in this way can accurately sample the signal of microampere order, provide the precondition accurately measured.
The voltage class of high pressure PT in the present invention is determined according to tested arrester rated voltage, is typically chosen in tested keep away
The 50%~100% of thunder device rated voltage.
The anti-interference frequency-selecting measuring device of high-precision strong can accurately measure faint non-power-frequency current letter under thousands of times of interference
Number.
Obviously, the above embodiment of the present invention be only to clearly illustrate example of the present invention, and not be pair
The restriction of embodiments of the present invention.For those of ordinary skill in the art, may be used also on the basis of the above description
To make other variations or changes in different ways.There is no necessity and possibility to exhaust all the enbodiments.It is all this
All any modification, equivalent and improvement made within the spirit and principle of invention etc., should be included in the claims in the present invention
Protection domain within.
Claims (6)
1. a kind of arrester Coupling Between Phases capacitance test method based on alien frequencies method, which is characterized in that measure A, B phase arrester
Coupling Between Phases capacitance for, include the following steps：
Step 1 determines that institute's survey arrester is in power failure, and A, B phase arrester upper end is hanging, and B phase arresters lower end is straight
Ground connection, A arresters lower end is also directly grounded, and a light current current transformer is accessed on its ground wire；
Step 2, frequency variation signal source output terminal connect the low-voltage terminal of high pressure PT, and the high voltage output terminal of PT connects the upper of B phase arresters
End, the shell of PT are directly grounded；
Step 3 exports the alien frequencies voltage signal U between a 40-70Hz using variable frequency signal source, pressurizes to B phases arrester；
Step 4 measures the non-power-frequency current I and variable frequency signal source of A phase arresters using the anti-interference frequency-selecting measuring device of high-precision strong
The alien frequencies voltage signal U of output；
Step 5, the no-load voltage ratio of PT is K, and the alien frequencies signal frequency of test is f, can calculate alternate coupling of A, B phase under frequency f
Close capacitance CAB=I/2πfUK；
Step 6 can similarly measure the Coupling Between Phases capacitance of B, C phase and A, C phase arrester respectively.
2. a kind of arrester Coupling Between Phases capacitance test method based on alien frequencies method according to claim 1, feature exist
In：In the step 1, arrester is the arrester without electricity operation.
3. a kind of arrester Coupling Between Phases capacitance test method based on alien frequencies method according to claim 1, feature exist
In：In the step 1, light current current transformer is connected on the ground wire of arrester, and measurement range is selected in 0~5mA.
4. a kind of arrester Coupling Between Phases capacitance test method based on alien frequencies method according to claim 1, feature exist
In：In the step 2, the voltage class of high pressure PT is determined according to the voltage class of tested arrester, the High voltage output of high pressure PT
Voltage is the 50%~100% of tested arrester rated voltage.
5. a kind of arrester Coupling Between Phases capacitance test method based on alien frequencies method according to claim 1, feature exist
In：In the step 4, the frequency-selecting measuring device of the anti-interference weak current of high-precision strong uses the frequency-selecting measuring technique of strong anti-interference.
6. the system of the application arrester Coupling Between Phases capacitance test method described in claim 1 based on alien frequencies method, feature
It is：Including being tested three-phase lightning protector, variable frequency signal source, high pressure PT, light current current transformer, the anti-interference frequency-selecting measurement of high-precision strong
Device, alternating current 220V power supplys, grounded screen, connecting line；
Alternating current 220V power supplys are connected to variable frequency signal source to system power supply；The output of variable frequency signal source is connected to the low pressure of high pressure PT
Terminal；The High voltage output of high pressure PT is connected to the upper end of B phase arresters, the earthing of casing of high pressure PT；A, B phases arrester upper end hangs
Sky, B phase arresters lower end are directly grounded, and A arresters lower end is also directly grounded, and a weak current mutual inductance is accessed on its ground wire
Device;The output of light current current transformer is connected to the current measurement terminal of the anti-interference frequency-selecting measuring device of high-precision strong, to the different of A phases
Frequency electric current measures, while the output of variable frequency signal source is connected to the voltage survey of the anti-interference frequency-selecting measuring device of high-precision strong
Terminal is measured, the no-load voltage ratio of high pressure PT is set in the anti-interference frequency-selecting measuring device of high-precision strong, A, B phase can be calculated automatically and taken shelter from the thunder
The Coupling Between Phases capacitance of device.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810215369.2A CN108181513B (en) | 2018-03-15 | 2018-03-15 | Inter-phase coupling capacitance testing method and system for lightning arrester based on pilot frequency method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810215369.2A CN108181513B (en) | 2018-03-15 | 2018-03-15 | Inter-phase coupling capacitance testing method and system for lightning arrester based on pilot frequency method |
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| CN108181513B CN108181513B (en) | 2020-02-04 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114167165A (en) * | 2021-11-12 | 2022-03-11 | 西南交通大学 | Lightning arrester valve plate service state evaluation method considering power pickup under multiple pulses |
| CN115060997A (en) * | 2022-06-22 | 2022-09-16 | 云南电网有限责任公司电力科学研究院 | Coil testing method, voltage transformer, system, computer device and medium |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114167165A (en) * | 2021-11-12 | 2022-03-11 | 西南交通大学 | Lightning arrester valve plate service state evaluation method considering power pickup under multiple pulses |
| CN115060997A (en) * | 2022-06-22 | 2022-09-16 | 云南电网有限责任公司电力科学研究院 | Coil testing method, voltage transformer, system, computer device and medium |
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| CN108181513B (en) | 2020-02-04 |
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