CN110531214A - For detecting the detection verification method of Secondary Circuit of Potential Transformer winding short circuit - Google Patents
For detecting the detection verification method of Secondary Circuit of Potential Transformer winding short circuit Download PDFInfo
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- CN110531214A CN110531214A CN201910803898.9A CN201910803898A CN110531214A CN 110531214 A CN110531214 A CN 110531214A CN 201910803898 A CN201910803898 A CN 201910803898A CN 110531214 A CN110531214 A CN 110531214A
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Abstract
The invention discloses a kind of for detecting the detection verification method of Secondary Circuit of Potential Transformer winding short circuit, it is related to the debugging maintenance field of voltage transformer in power plant/substation, including following processing step: measuring the electrical parameter of each secondary winding one by one to obtain the measurement electrical parameter of each secondary winding；The measurement electrical parameter of each secondary winding is compared with the first default electrical parameter values of this winding respectively, judges whether corresponding secondary winding occurs short circuit, obtains the judging result of each secondary winding；When judging result is that the judging result that each secondary winding does not occur that short circuit does not occur to each secondary winding under short circuit condition, one by one is verified.The check process that the present invention passes through measurement, judgement, verifying, it is whether short-circuit that verifying secondary winding can quickly and effectively be detected, and the instrument that detection verifying uses is light, and it is easy to operate, reliable and secure, effectively reduce the probability that human-equation error causes voltage transformer secondary short trouble.
Description
Technical field
It is the present invention relates to the debugging maintenance of voltage transformer in power plant/substation, in particular to a kind of for detecting electricity
Press the detection verification method of transformer secondary circuit winding short circuit.
Background technique
For voltage transformer (hereinafter referred to as PT), in its operation, if short trouble, secondary winding occur for secondary winding
Very big short circuit current can be generated, PT is caused to burn, therefore will check PT secondary winding before PT operation, confirmation is without short-circuit event
Barrier.
The existing main method for checking PT secondary winding short trouble is that measurement PT winding directly hinders and PT no-load voltage ratio.Such as Fig. 1 institute
Show, the method that measurement PT winding directly hinders are as follows: air switch 1JA, 2JA in open terminal case are opened using general-purpose table look-up air
The resistance value for closing downstream load circuit since PT secondary circuit load resistance is generally all very big, therefore passes through measurement load loop
Resistance value is easy to judge PT secondary load with the presence or absence of short trouble.But PT secondary winding directly hinders very little, generally less than 0.5
Ω, so being difficult to measure resistance value with multimeter to judge PT secondary winding and lead-out wire with the presence or absence of short trouble；It is another
The conventional method for checking PT secondary winding short trouble is measurement PT no-load voltage ratio, but when encountering PT secondary winding short trouble, is held
Measuring instrument easy to damage.And measurement PT winding directly hinders and the instrument of PT no-load voltage ratio is cumbersome, instrument, which needs to connect external power supply, can just make
With time of measuring is more long.Voltage transformer will carry out scheduled maintenance every year, a kind of for detecting voltage therefore, it is necessary to design
The detection verification method of transformer secondary circuit winding short circuit not only ensures voltage transformer stable operation, also saves PT power transmission
The time of operation.
Summary of the invention
In order to solve problems in the prior art, the present invention provides one kind for detecting Secondary Circuit of Potential Transformer winding
Short circuit can effectively reduce the detection verification method that human-equation error causes voltage transformer secondary short trouble probability.
The technical solution that the present invention is proposed with regard to above-mentioned technical problem is as follows: one kind is returned for detecting voltage transformer secondary
The detection verification method of road winding short circuit, the voltage transformer include at least one group of first winding and two groups of secondary windings, institute
The method of stating includes the following steps:
S1, measuring process: the electrical parameter of each secondary winding is measured one by one to obtain the measurement electricity of each secondary winding ginseng
Number；
S2, judgment step: respectively by the first default electricity ginseng of the measurement electrical parameter of each secondary winding and this winding
Numerical value is compared, and judges whether corresponding secondary winding occurs short circuit, obtains the judging result of each secondary winding；
S3, verification step: each secondary winding does not occur not occurring under short circuit condition, one by one to each secondary winding short
The judging result on road is verified.
Wherein, it is described when judging result be each secondary winding do not occur under short circuit condition, one by one to it is each it is secondary around
Judging result the step of being verified that short circuit does not occur for group includes following processing: determine that will verify a secondary winding, point
Under the other secondary winding verified to needs and other secondary windings setting short circuit operation, this that be verified secondary winding is measured respectively
Electrical parameter, be verified electrical parameter, by each verifying electrical parameter and verifying secondary winding measurement electrical parameter carry out difference comparsion,
If difference is greater than the second preset value, verifies the secondary winding and short circuit does not occur；Successively separately verify all secondary windings.
Wherein, two groups of secondary windings include the first secondary winding and second secondary winding, when the first secondary winding and
When the measurement electrical parameter of second secondary winding is respectively greater than the first preset value of corresponding secondary winding, tentatively judge corresponding secondary
Short circuit does not occur for winding, when judging result is that the first secondary winding and second secondary winding do not occur under short circuit condition, one by one
The judging result that short circuit does not occur to the first secondary winding and second secondary winding is verified.
Wherein, the judging result that short circuit does not occur to the first secondary winding and second secondary winding one by one is verified
Step specifically includes following processing:
The first secondary winding is verified, in the case where carrying out short circuit respectively to the first secondary winding or second secondary winding, is surveyed
The electrical parameter of one secondary winding of flow control obtains two verifying electrical parameters of the first secondary winding, and two of the first secondary winding are tested
Card electrical parameter is compared two differences that the first secondary winding is calculated with the measurement electrical parameter of the first secondary winding respectively,
If the first difference of secondary winding two be greater than the first secondary winding the second preset value, verification result be the first secondary winding not
Short circuit occurs；Second secondary winding is verified, in the case where carrying out short circuit respectively to second secondary winding or the first secondary winding, is surveyed
The electrical parameter of two secondary winding of flow control obtains two verifying electrical parameters of second secondary winding, and two of second secondary winding are tested
Card electrical parameter is compared two differences that second secondary winding is calculated with the measurement electrical parameter of second secondary winding respectively,
If two differences of second secondary winding are greater than the second preset value of second secondary winding, verification result is second secondary winding
Short circuit does not occur.
Wherein, the measurement electrical parameter includes the voltage parameter for measuring the first secondary winding and second secondary winding, is used
Battery and voltmeter are connected respectively the winding terminal in the first secondary winding and second secondary winding, pass through battery and voltmeter
Method checks that the secondary circuit of voltage transformer whether there is short trouble.
Wherein, the measurement voltage parameter for obtaining first secondary winding includes following processing: voltmeter is connected to the
The both ends of one secondary winding, one end of battery connect one end of second secondary winding, the other end overlap joint of battery it is second secondary around
The other end of group reads the voltmeter throw of pointer situation of the first secondary winding of connection during the lapping process, it is secondary to obtain first
The measurement voltage parameter of winding；The measurement voltage parameter for obtaining the second secondary winding includes following processing: voltmeter is connected
It connects at the both ends of second secondary winding, one end of battery connects one end of the first secondary winding, the other end overlap joint first of battery
The other end of secondary winding reads the voltmeter throw of pointer situation for connecting second secondary winding during the lapping process, obtains the
The measurement voltage parameter of two secondary windings.
Wherein, carrying out verification process to the measurement voltage parameter of obtained first and second secondary winding includes: point
It is other that the first or second secondary winding for connecting the voltmeter is shorted, and battery one end is respectively corresponded and is overlapped on second
Or first secondary winding one end, respectively obtain the first certificate parameter of the first secondary winding, the second of the first secondary winding is tested
Demonstrate,prove parameter, the second certificate parameter of the first certificate parameter of second secondary winding and second secondary winding；By each certificate parameter
It is compared with the measurement voltage parameter between not being shorted, if difference is greater than its corresponding second preset value, judges that first is secondary
Short circuit does not occur for winding and second secondary winding.
Wherein, a winding is connected using inductance measuring meter, measures the inductance parameters of the winding, then inductance measuring meter is connected
Another winding is connect, to measure the inductance parameters of each winding one by one, the inductance parameters and first that measurement is obtained are preset
Inductance value is compared, and judges whether corresponding secondary winding occurs short circuit, obtains the judging result of each secondary winding, if hair
Raw short circuit, measurement terminate, if short circuit does not occur for judgement, enter verification step.
Wherein, the step of inductance parameters of each winding of measurement and verifying correspond to inductance parameters specifically includes as follows
Processing: measuring process: secohmmeter is connected to the both ends of the first secondary winding or second secondary winding, and second secondary winding is opened
Road or the first secondary winding, measurement obtains the inductance parameters of the first secondary winding or second secondary winding respectively；Verification step: first
The both ends that secohmmeter is first connected to the first secondary winding or second secondary winding, are shorted the first secondary winding or second secondary winding
Both ends, read the first secondary winding of secohmmeter or the inductance parameters of second secondary winding, respectively obtain the first secondary winding
First verifying inductance parameters, the first secondary winding second verifying inductance parameters, second secondary winding first verifying inductance
Second verifying inductance parameters of parameter and second secondary winding；Measurement inductance between not being shorted each verifying inductance parameters and
Parameter is compared, if difference is greater than its corresponding second default inductance value, judges the first secondary winding and second secondary winding
Short circuit does not occur.
Wherein: further including production battery case step, be fixed in battery case using 2 section 9V batteries, battery case draws wiring.
Technical solution provided in an embodiment of the present invention has the benefit that
It is provided in an embodiment of the present invention a kind of for detecting the detection authentication of Secondary Circuit of Potential Transformer winding short circuit
Method, by measuring the electrical parameter of each secondary winding one by one to obtain the measurement electrical parameter of each secondary winding；It respectively will be each
The measurement electrical parameter of secondary winding is compared with the first default electrical parameter values of this winding, whether judges corresponding secondary winding
Short circuit occurs, obtains the judging result of each secondary winding；When judging result is that short circuit condition does not occur for each secondary winding
Under, one by one to each secondary winding do not occur short circuit judging result verify.This measurement and verification step is easy to operate can
It leans on, effectively reduces the probability that human-equation error causes voltage transformer secondary short trouble；And the measuring instrument used is simple
It is light.
Detailed description of the invention
To describe the technical solutions in the embodiments of the present invention more clearly, make required in being described below to embodiment
Attached drawing is briefly described, it should be apparent that, drawings in the following description are only some embodiments of the invention, for
For those of ordinary skill in the art, without creative efforts, it can also be obtained according to these attached drawings other
Attached drawing.
Fig. 1 is the application scenario diagram of the prior art；
Fig. 2 is the second loop return wiring schematic diagram of voltage transformer of the present invention；
Fig. 3 is the embodiment of the present invention one for detecting the detection verification method of Secondary Circuit of Potential Transformer winding short circuit
General flow chart；
Fig. 3 a is that the verifying electrical parameter of the embodiment of the present invention one obtains flow chart；
Fig. 3 b is the judgment step flow chart of the verification process of the embodiment of the present invention one；
Fig. 3 c is the measurement electric parameter measurement flow chart of steps of the embodiment of the present invention one；
Fig. 3 d is the verification process flow chart of the embodiment of the present invention one；
Fig. 4 is the step flow chart that the battery method of the embodiment of the present invention two checks the PT of PT secondary winding short trouble；
Fig. 5 is the schematic diagram that a kind of battery method provided by Embodiment 2 of the present invention checks PT secondary winding short trouble；
Fig. 6 is the PT second short circuit that a kind of battery method provided by Embodiment 2 of the present invention checks PT secondary winding short trouble
Failure schematic diagram；
Fig. 7 is the PT step that a kind of inductance measuring that the embodiment of the present invention three provides checks PT secondary winding short trouble
Flow chart；
Fig. 8 is that a kind of inductance measuring that the embodiment of the present invention three provides checks that the PT of PT secondary winding short trouble is equivalent
Circuit diagram.
Specific embodiment
, instrument needs cumbersome with the instrument of PT no-load voltage ratio are directly hindered in order to solve the measurement PT winding in the presence of the prior art
Connecing external power supply could use, and time of measuring is more long, and because secondary windings of PT directly hinder it is inclined smaller, using measurement
The method that PT winding directly hinders be easy to cause no judgement, using the method for measurement PT no-load voltage ratio, when encountering PT secondary winding short trouble
When, the problem of being easily damaged measuring instrument, the present invention is intended to provide a kind of verifying secondary winding short-circuit conditions of can effectively detecting
Method, core concept are: providing a kind of for detecting the detection verification method of Secondary Circuit of Potential Transformer winding short circuit, sheet
Invention uses electric parameter measurement instrument, measures the measurement electrical parameter of secondary winding first, then with the first preset value for having provided
It is compared.If measuring electrical parameter less than the first preset value, it is judged as that short circuit occurs for secondary winding.If measurement electrical parameter is greater than
First preset value is then tentatively judged as that short circuit does not occur for secondary winding.It is the feelings that secondary winding is generation short circuit in judging result
Under condition, the verifying electrical parameter of secondary winding is measured, measurement electrical parameter and verifying electrical parameter are subjected to difference calculating, if difference calculates
Result be greater than the second preset value for having provided, then it is not short-circuit to verify secondary winding.Otherwise authentication failed needs to re-start inspection
Test card process, or search the reason of other lead to authentication failed.By this method, verifying secondary winding can be effectively detected
It is whether short-circuit, and the instrument that detection verifying uses is light, operation is simple and reliable, and then effectively reduces human-equation error and cause voltage
The probability of mutual inductor second short circuit failure.
Embodiment one
The embodiment of the invention provides a kind of for detecting the detection authentication of Secondary Circuit of Potential Transformer winding short circuit
Method is particularly suitable in power plant or substation, and referring to Fig. 3, this method may include following key step:
Step S1, measuring process: the electrical parameter of each secondary winding is measured one by one to obtain the measurement of each secondary winding
Electrical parameter.
It should be noted that unknown current secondary winding whether short circuit in the case where, need using corresponding method and
Instrument carries out electric parameter measurement to each secondary winding, obtains it and measures electrical parameter, and the purpose is to for presetting electricity ginseng with first
Several comparisons, and then complete secondary circuit winding short circuit and test and analyze.
Further, the present embodiment use measurement take the method for mean value three times obtain measurement electrical parameter as a result, with reduce
Measurement error.
It in the present embodiment, referring to fig. 2, is the second loop return wiring schematic diagram of voltage transformer voltage transformer, wherein
It include: the voltage transformer cabinet and terminal box being attached by aviation plug.Voltage transformer cabinet storage has voltage transformer,
Three groups of secondary winding ends of voltage transformer are drawn, the both ends of aviation plug be utilized respectively conducting wire connection it is corresponding three groups it is secondary
Winding is verified for short-circuit detecting.Three groups of secondary windings in terminal box, respectively a1n1, a2n2, a3n3, each secondary
The downstream of winding is corresponding respectively to connect having air switch A1J, A2J, A3J, is connected respectively three in the downstream of air switch
Group load.Based on above-mentioned measuring process, to secondary winding a1n1, a2n2, the air switch A1J, A2J, A3J in the downstream a3n3 are disconnected
It opens, then individually accesses electrical measuring instrument, measure three groups of respective measurement electrical parameters.
Step S2, judgment step: the measurement electrical parameter of each secondary winding is preset with the first of this winding respectively
Electrical parameter values are compared, and judge whether corresponding secondary winding occurs short circuit, obtain the judging result of each secondary winding.
In the present embodiment, referring to fig. 2, by the measurement electrical parameter of secondary winding a1n1 and the secondary winding a1n1 provided
The first default electrical parameter values be compared.Likewise, by the measurement electrical parameter of secondary winding a2n2 with provided it is secondary around
The first default electrical parameter values of group a2n2 are compared.By the measurement electrical parameter of secondary winding a3n3 and the secondary winding provided
The default electrical parameter values of the first of a3n3 are compared.Judge whether corresponding secondary winding occurs short circuit.Further, as right
Than the first default electrical parameter (taken with the measurement electrical parameter in step S1 using identical electrical unit and numerical precision respectively
It is worth 2 significant digits), and then promote the normalization of comparison method.When judging result is that short circuit occurs for secondary winding, directly
Terminate check process, the review time can be saved.
Step S3, verification step: when judging result is that each secondary winding does not occur under short circuit condition, one by one to each
The judging result that short circuit does not occur for secondary winding is verified.
In the present embodiment, the method for verifying uses difference comparsion method.With reference to Fig. 2, first one by one using electrical measuring instrument
Measure the verifying electrical parameter of the first secondary winding a1n1, a2n2 and a3n3.Using corresponding instrument, in independent short-circuit secondary winding
In the case where a1n1, a2n2, a3n3, the electrical parameter of a1n1 is measured, obtains the first verifying electrical parameter, second of secondary winding a1n1
It verifies electrical parameter and third verifies electrical parameter；Similar, in the case where independent short-circuit secondary winding a1n1, a2n2, a3n3, point
Not Ce Liang a2n2, a3n3 electrical parameter, can be obtained secondary winding a2n2 and a3n3 it is respective first verifying electrical parameter, second verifying
Electrical parameter and third verify electrical parameter.Then respective verifying electrical parameter is subjected to difference calculating with corresponding measurement electrical parameter.
If difference is greater than respective second preset value, it is not short-circuit to verify the secondary winding, completes check process.It has been given if difference is less than
The second preset value out, then return step S1, restarts check process.So, which both may be implemented pair
The verifying of judging result, improves the reliability of inspection result, and may be constructed complete inspection logic and return when validation failure
It returns step S1 and reexamines or check the reason of other cause authentication error.
Described when judging result is that each secondary winding does not occur under short circuit condition, one by one to each secondary winding not
It includes following processing that the step of short-circuit judging result is verified, which occurs:
Secondary winding will be verified by determining one, short to the secondary winding for needing to verify and the setting of other secondary windings respectively
Under dataway operation, measure the electrical parameter of this that be verified secondary winding respectively, be verified electrical parameter, by each verifying electrical parameter and
It verifies secondary winding measurement electrical parameter and carries out difference comparsion, if difference is greater than the second preset value, verifies the secondary winding and do not send out
Raw short circuit；Successively separately verify all secondary windings.
In the present embodiment, it is verified using difference comparsion method, referring to Fig. 3 a, measures the verifying electricity of each winding first
Parameter, for example, the verifying electrical parameter of the first secondary winding a1n1 of measurement: the first secondary winding a1n1 of independent short circuit is surveyed with instrument
The electrical parameter of one secondary winding a1n1 of flow control obtains the first verifying electrical parameter of the first secondary winding a1n1；Individually short circuit second
Secondary winding a2n2, with the electrical parameter of the first secondary winding of instrument measurement a1n1, obtain the first secondary winding a1n1 second is tested
Demonstrate,prove electrical parameter；Since there are multiple groups secondary windings in the terminal box of voltage transformer, according to the method described above, and so on, it can be with
Obtain all verifying electrical parameters of the first secondary winding a1n1；Further, the instrument measurement object in the above method is changed into
Instrument measurement object, is changed into the three or two by two secondary windings, all verifying electrical parameters of available second secondary winding a2n2
Secondary winding, all verifying electrical parameters ... and so on of available third secondary winding a3n3 are available all secondary
The corresponding all verifying electrical parameters of winding.Further, measuring process needs to carry out to measure three times to be averaged, and is missed with reducing measurement
Difference, and measurement result retains 2 significant digits, can guarantee the accuracy of measurement result in this way.After being verified electrical parameter,
Referring to Fig. 3 b, measurement electrical parameter and verifying electrical parameter are subjected to difference calculating, i.e., difference=| measurement electrical parameter-verifying electrical parameter
|, then the absolute value result is compared with the second preset value provided, if difference is greater than the second preset value, verifying pair
As secondary winding is not short-circuit, check process is completed.If difference is less than the second preset value for having provided, return step S1, again
Start check process.According to this sequence flow, it is successively respectively completed the verifying of all secondary windings.It is all due to having traversed
Short-circuit possibility, so verification result possesses high reliability.
For measuring verification method: two groups of secondary windings include the first secondary winding and second secondary winding, when the
When the measurement electrical parameter of one secondary winding and second secondary winding is respectively greater than the first preset value of corresponding secondary winding, tentatively sentence
Short circuit does not occur for corresponding secondary winding of breaking, when judging result is that short circuit does not occur for the first secondary winding and second secondary winding
Under the conditions of, the judging result that short circuit does not occur to the first secondary winding and second secondary winding one by one is verified.
In the present embodiment, referring to Fig. 3 c, the acquisition for measuring electrical parameter is completed according to the following steps: firstly, disconnecting first
Then the air switch A1J in the downstream secondary winding a1n1 is independently accessed instrument and measures to the first secondary winding a1n1, obtains
The measurement electrical parameter of first secondary winding a1n1；Then, the air switch A2J in the downstream second secondary winding a2n2 is disconnected, then
It is independently accessed instrument to measure to second secondary winding a2n2, obtains the measurement electrical parameter of second secondary winding a2n2；Then,
Then the air switch A3J for disconnecting the downstream second secondary winding a3n3 is independently accessed instrument and carries out to third secondary winding a3n3
Measurement, obtains the measurement electrical parameter of third secondary winding a3n3；Due in the terminal box of mutual induction of voltage there are multiple groups secondary winding,
According to the method described above, and so on, obtain the measurement electrical parameter of all secondary windings.Further, measuring process needs to carry out three
Secondary measurement is averaged, and to reduce measurement error, and measurement result retains 2 significant digits, can guarantee measurement result in this way
Accuracy.The judging result that short circuit does not occur to the first secondary winding and second secondary winding one by one carries out verification step
Specifically include following processing:
The first secondary winding is verified, in the case where carrying out short circuit respectively to the first secondary winding or second secondary winding, is surveyed
The electrical parameter of one secondary winding of flow control obtains two verifying electrical parameters of the first secondary winding, and two of the first secondary winding are tested
Card electrical parameter is compared two differences that the first secondary winding is calculated with the measurement electrical parameter of the first secondary winding respectively,
If the first difference of secondary winding two be greater than the first secondary winding the second preset value, verification result be the first secondary winding not
Short circuit occurs；
Second secondary winding is verified, in the case where carrying out short circuit respectively to second secondary winding or the first secondary winding, is surveyed
The electrical parameter of two secondary winding of flow control obtains two verifying electrical parameters of second secondary winding, and two of second secondary winding are tested
Card electrical parameter is compared two differences that second secondary winding is calculated with the measurement electrical parameter of second secondary winding respectively,
If two differences of second secondary winding are greater than the second preset value of second secondary winding, verification result is second secondary winding
Short circuit does not occur.
In the present embodiment, referring to Fig. 3 d, the first secondary winding a1n1 or second secondary winding a2n2 are carried out respectively short
In the case where road, the electrical parameter of the first secondary winding a1n1 of measurement obtains two verifying electrical parameters of the first secondary winding a1n1,
Two verifying electrical parameters of first secondary winding a1n1 are compared with the measurement electrical parameter of the first secondary winding a1n1 respectively
Two differences of the first secondary winding a1n1 are calculated, if two differences of the first secondary winding a1n1 are greater than the first secondary winding
The second preset value, then verification result be the first secondary winding a1n1 short circuit does not occur；According to the above method, measurement object is changed
For second secondary winding a2n2 or third secondary winding a3n3, available second or respective two verifyings of third secondary winding
Electrical parameter.Second or the respective verifying electrical parameter of third secondary winding are compared calculating with respective measurement electrical parameter respectively
Two differences of secondary winding a2n2 or a3n3 are obtained, if two differences of second secondary winding a2n2 are greater than second secondary winding
Second preset value, then verification result is that short circuit does not occur for second secondary winding a2n2, if two differences of third secondary winding a3n3
Greater than the second preset value of third secondary winding, then verification result is that short circuit does not occur for third secondary winding a3n3；Due to secondary
When winding has occurred and that short circuit, verifying electrical parameter is close with electrical parameter is measured, the difference very little of the two, therefore can set the
Two preset values are as thresholding, when difference is less than the second preset value, are determined as that short circuit occurs for secondary winding, when difference is greater than second
When preset value, it is determined as that short circuit does not occur for secondary winding.Specifically, since there are multiple groups two in the terminal box of voltage transformer
Secondary winding is measured selected so needing to select a secondary winding, then individually short-circuit all secondary windings with measuring instrumentss
All verifying electrical parameters of secondary winding, then the progress of the measurement electrical parameter of all verifying electrical parameters of the winding and the winding is poor
Value calculates, and calculated result is compared with the second preset value that the winding has provided.If difference is greater than the second preset value,
It is not short-circuit to verify the winding.Otherwise it needs to restart check process or checks the reason of other lead to authentication failed.According to upper
Step is stated, all secondary winding judging results for being judged as not short circuit for the first time are successively verified.This detection verification method can mention
The reliability of high inspection result.
Embodiment two
The present invention provides the methods of a kind of " battery method checks PT secondary winding short trouble ", referring to fig. 4, this method packet
It includes:
Measure electrical parameter:
The measurement electrical parameter includes the voltage parameter for measuring the first secondary winding and second secondary winding, using battery and
Voltmeter is connected respectively the winding terminal in the first secondary winding and second secondary winding, passes through battery and voltmeter method inspection
The secondary circuit of voltage transformer whether there is short trouble.Wherein the first secondary winding is a1n1, and second secondary winding is
a2n2。
In the present embodiment, the measurement voltage parameter for obtaining first secondary winding includes following processing: by voltmeter
It is connected to the both ends of the first secondary winding, one end of battery connects one end of second secondary winding, the other end overlap joint of battery the
The other end of two secondary windings reads the voltmeter throw of pointer situation of the first secondary winding of connection during the lapping process, obtains
The measurement voltage parameter of first secondary winding；The measurement voltage parameter for obtaining the second secondary winding includes following processing: will
Voltmeter is connected to the both ends of second secondary winding, and one end of battery connects one end of the first secondary winding, the other end of battery
The other end of the first secondary winding is overlapped, reads the voltmeter throw of pointer feelings for connecting second secondary winding during the lapping process
Condition obtains the measurement voltage parameter of second secondary winding.Specifically, referring to Fig. 5, when one secondary winding of voltage transformer pt
After battery is accessed at both ends, electric current can generate magnetic flux in PT iron core, and PT main flux is caused to change.Main flux variation can once around
Voltage is induced in group and other secondary windings, causes milivoltmeter throw of pointer.If the secondary winding of pressurization there are short trouble,
Secondary winding is short-circuited, and is generated magnetic flux in PT iron core without electric current, will not be generated induced voltage, therefore millivolt list index will not be inclined
Turn.Referring to Fig. 6, if there are short troubles for the secondary winding of connection milivoltmeter, the voltage of milivoltmeter measurement is the electricity of short-circuit loop
Pressure, essentially 0, therefore pointer will not deflect substantially.
Carrying out verification process to the measurement voltage parameter of obtained first and second secondary winding includes:
The first or second secondary winding for connecting the voltmeter is shorted respectively, and battery one end is respectively corresponded
Be overlapped on one end of the second or first secondary winding, respectively obtain the first secondary winding the first certificate parameter, first it is secondary around
The second certificate parameter, the second certificate parameter of the first certificate parameter of second secondary winding and second secondary winding of group；
By each certificate parameter be not shorted between measurement voltage parameter be compared, if difference be greater than its corresponding the
Two preset values judge that short circuit does not occur for the first secondary winding and second secondary winding.
In the present embodiment, referring to Fig. 6, the first secondary winding a1n1 is shorted, battery accesses second secondary winding,
Measure the voltage of a1n1, the first verifying electrical parameter of available a1n1.Second secondary winding a2n2 is shorted, battery access the
Two secondary windings measure the voltage of a1n1, the second verifying electrical parameter of available a1n1.And so on, available second
First verifying electrical parameter of secondary winding and the second verifying electrical parameter.Further, the verifying electrical parameter is voltage, and unit is
MV, numerical value get 2 significant digits.Further, due to using milivoltmeter, instrument is light, and operation is simple and reliable, so
Effectively reduce the probability that human-equation error causes voltage transformer secondary short trouble.
The present embodiment further include: production battery case step is fixed in battery case using 2 section 9V batteries, and battery case is drawn
Wiring.Referring to Fig. 5, Fig. 6, which is used for the power supply of battery method, can produce magnetic flux, so that milivoltmeter be allowed to deflect.
Here, being verified to above description:
Battery case is made first, is fixed in battery case using 2 section 9V batteries, and battery case draws wiring, then at the end PT
Secondary circuit is disconnected in sub- case to be spaced apart, and needle dc voltmeter is connected on 2 circuit of secondary winding.
Then anode is connected to the a1 (link position is to be spaced apart upper port) of secondary winding 1, and battery cathode is not connected to.
Battery cathode is quickly touched to the n1 (link position is to be spaced apart upper port) of secondary winding 1 again, observation milivoltmeter refers to
Needle deflection situation obtains measurement voltage parameter, is recorded in table 1.Respectively by secondary winding 1 and secondary in voltage transformer cabinet
2 short circuit of winding, is pressurizeed using the above method and observes milivoltmeter throw of pointer situation, be verified voltage parameter, and be recorded in table 1
In.
Deflection situation when 1 secondary winding 1 of table is pressurizeed
Finally needle dc voltmeter is connected on 1 circuit of secondary winding, pressurizes, repeats above-mentioned in 2 circuit of secondary winding
Step is observed voltmeter throw of pointer situation and is recorded in table 2.
Deflection situation when 2 secondary winding 2 of table is pressurizeed
Referring to Tables 1 and 2, it is known that either pressurization winding still measures winding there are when short trouble, milivoltmeter
Pointer hardly deflects, and when secondary winding is normal, milivoltmeter throw of pointer no to scale.
Assuming that milivoltmeter range 200mV, sets one preset value of voltage regulation as 150mV, two preset value of voltage regulation is 20mV.In
When secondary winding is normal, milivoltmeter throw of pointer is greater than 200mV, therefore is necessarily greater than one preset value of voltage regulation, can correctly judge
Secondary winding is normal.When carrying out the verifying of subsequent " not short circuit ", because measurement electrical parameter is greater than 200mV, secondary winding short circuit
When verifying electrical parameter go to zero, so the difference of the two is necessarily greater than two preset value of voltage regulation, can with correct verification it is secondary around
Group is normal；In secondary winding short circuit, because millivolt list index hardly deflects, measurement electrical parameter must be much smaller than voltage
First preset value can correctly judge that secondary winding has short circuit.
Embodiment three
The present invention provides the methods of a kind of " inductance measuring checks PT secondary winding short trouble ", referring to Fig. 7, the party
Method includes:
A winding is connected using inductance measuring meter, measures the inductance parameters of the winding, then inductance measuring meter is connected separately
An outer winding, to measure the inductance parameters of each winding one by one, inductance parameters and the first preset inductance that measurement is obtained
Value is compared, and judges whether corresponding secondary winding occurs short circuit, obtains the judging result of each secondary winding, if occurring short
Road, measurement terminate, if short circuit does not occur for judgement, enter verification step.Specifically, comprising the following steps:
Secohmmeter: being connected the both ends of the first secondary winding or second secondary winding by measuring process, and by it is second secondary around
Group open circuit or the first secondary winding, measurement obtains the inductance parameters of the first secondary winding or second secondary winding respectively；
Secohmmeter: being connected the both ends of the first secondary winding or second secondary winding by verification step first, is shorted the one or two
The first secondary winding of secohmmeter or the inductance parameters of second secondary winding are read in the both ends of secondary winding or second secondary winding,
Respectively obtain the first verifying inductance parameters of the first secondary winding, the second verifying inductance parameters, the two or two of the first secondary winding
First verifying inductance parameters of secondary winding and the second verifying inductance parameters of second secondary winding；
By it is each verifying inductance parameters be not shorted between measurement inductance parameters be compared, if difference be greater than its correspond to
The second default inductance value, judge that short circuit does not occur for the first secondary winding and second secondary winding.
In the present embodiment, referring to Fig. 8, first using LCR table connect the first secondary winding a1n1, measurement first it is secondary around
The measurement inductance parameters of group a1n1, then connect second secondary winding a2n2 using LCR table, measure second secondary winding a2n2's
Measure inductance parameters.Then obtained measurement inductance parameters are compared with the first preset inductance value (650uH) provided
Compared with judging whether corresponding secondary winding occurs short circuit.If measuring inductance parameters is greater than the first default inductance value, the winding is not
Short circuit occurs, it is on the contrary then short circuit has occurred.If short circuit does not occur, enter verification step: firstly, short-circuit first secondary winding
A1n1, and with the inductance value of the first secondary winding a1n1 of LCR table measurement, obtain the first secondary winding a1n1 first verifies inductance
Parameter, then, the second secondary winding a2n2 of short circuit, and with the inductance value a1n1 of LCR table the first secondary winding of measurement, obtain first
The second verifying inductance parameters of secondary winding a1n1；And so on, the first and second of available second secondary winding a2n2
Verify inductance parameters.Then, the verifying inductance parameters and the measurement inductance parameters are subjected to difference calculating, then institute will be calculated
The absolute value result obtained is compared with the second default inductance value (200uH) provided, if difference is greater than the second default inductance
Value is then verified not short-circuit.Otherwise restart checking step or check the reason of other cause authentication failed.Due to using
LCR table, instrument is light, and operation is simple and reliable, so effectively reducing human-equation error causes voltage transformer secondary short trouble
Probability.
Further, this method realizes calculating and judgement based on the series-parallel Computing Principle of inductance, specifically, voltage is mutual
First and second winding of sensor is all wrapped on iron core, and general inductance is larger, if there are short trouble, inductance value meetings for secondary circuit
It changes.As shown in figure 8, when PT secondary winding is normal, PT secondary circuit inductance L2=X2 '+Xm, L3=X3 '+Xm.When two
When there is short trouble in secondary winding, as shown in figure 8, at this moment L2 meeting very little, while L3=X3 '+Xm//X2 ', can also it become smaller.Therefore it can
To use the inductance value of inductance measuring meter measurement secondary circuit to determine whether there are short troubles.
Here, being verified to above description:
Secondary circuit is disconnected first in PT terminal box to be spaced apart, and measures secondary winding 1 using LCR table and secondary winding 2 is returned
The inductance value on road obtains measurement inductance parameters, is recorded in table 3.Then respectively by 1 He of secondary winding in voltage transformer cabinet
2 short circuit of secondary winding obtains measurement inductance parameters using the inductance value of LCR table measurement secondary winding 1 and 2 circuit of secondary winding,
It is recorded in table 3.
3 inductance measurements of table
Referring to table 3, it is known that when secondary winding is normal, inductance value is respectively 773uH and 796uH, when secondary winding short circuit, electricity
Inductance value substantially reduces.
The first preset value of inductance is set as 650uH, the second preset value of inductance is 200uH.When secondary winding is normal, measurement
Inductance parameters are greater than 700uH, therefore are necessarily greater than the first preset value of inductance, can correctly judge that secondary winding is normal.Then into
When row result verification, verifying electrical parameter when due to secondary winding short circuit is respectively less than 150uH, so measurement electrical parameter and verifying electricity
The difference of parameter is necessarily greater than 500uH, is equally also necessarily greater than the second preset value of inductance, can be not short with correct verification secondary winding
The result on road；In secondary winding short circuit, inductance value is up to 122.2uH, so it must be much smaller than the first preset value of inductance, it can
Correctly to judge secondary winding short circuit.
It should be noted that the parameter used in the embodiment of the present invention is only an example, according to specific application scenarios,
Need to set different parameter values.In addition, battery method and inductance measuring can accurately check PT secondary winding short trouble.Electricity
Pond method only needs a batteries and a milivoltmeter, and inductance measuring only needs a LCR table, directly hinders and PT compared to existing PT winding
No-load voltage ratio measurement method, it is easy to operate quick.Between the two, inductance measuring operation is relatively easy for battery method and inductance measuring,
But the generally noninductive delivery test value of PT secondary winding, therefore need to be surveyed in the case where confirmation PT secondary winding is without short circuit fault condition
Measure the inductance value of PT secondary winding, the standard as subsequent examination.
Claims (10)
1. a kind of for detecting the detection verification method of Secondary Circuit of Potential Transformer winding short circuit, the voltage transformer is at least
Including one group of first winding and two groups of secondary windings, which is characterized in that described method includes following steps:
Measuring process: the electrical parameter of each secondary winding is measured one by one to obtain the measurement electrical parameter of each secondary winding；
Judgment step: the first default electrical parameter values of the measurement electrical parameter of each secondary winding and this winding are carried out respectively
Compare, judge whether corresponding secondary winding occurs short circuit, obtains the judging result of each secondary winding；
Verification step: when judging result is that each secondary winding does not occur under short circuit condition, one by one to each secondary winding not
The judging result that short circuit occurs is verified.
2. detection verification method according to claim 1, which is characterized in that described when judging result is each secondary winding
The step of judging result for not occurring that short circuit does not occur to each secondary winding under short circuit condition, one by one is verified includes such as
Lower processing:
Secondary winding will be verified by determining one, respectively to the secondary winding for needing to verify and other secondary windings setting short circuit behaviour
Under work, the electrical parameter of this that be verified secondary winding is measured respectively, is verified electrical parameter, by each verifying electrical parameter and verifying
Secondary winding measure electrical parameter carry out difference comparsion, if difference be greater than the second preset value, verify the secondary winding do not occur it is short
Road；Successively separately verify all secondary windings.
3. detection verification method according to claim 2, it is characterised in that: two groups of secondary windings include first secondary
Winding and second secondary winding, when the measurement electrical parameter of the first secondary winding and second secondary winding be respectively greater than it is corresponding it is secondary around
Group the first preset value when, tentatively judge that short circuit does not occur for corresponding secondary winding, when judging result be the first secondary winding and
Second secondary winding does not occur under short circuit condition, and short circuit does not occur to the first secondary winding and second secondary winding one by one and sentences
Disconnected result is verified.
4. detection verification method according to claim 3, it is characterised in that:
It is specific that the judging result that short circuit does not occur to the first secondary winding and second secondary winding one by one carries out verification step
Including handling as follows:
The first secondary winding is verified, in the case where carrying out short circuit respectively to the first secondary winding or second secondary winding, measurement the
The electrical parameter of one secondary winding obtains two verifying electrical parameters of the first secondary winding, by two verifyings electricity of the first secondary winding
Parameter is compared two differences that the first secondary winding is calculated with the measurement electrical parameter of the first secondary winding respectively, if the
One difference of secondary winding two is greater than the second preset value of the first secondary winding, then verification result is that the first secondary winding does not occur
Short circuit；
Second secondary winding is verified, in the case where carrying out short circuit respectively to second secondary winding or the first secondary winding, measurement the
The electrical parameter of two secondary windings obtains two verifying electrical parameters of second secondary winding, by two verifyings electricity of second secondary winding
Parameter is compared two differences that second secondary winding is calculated with the measurement electrical parameter of second secondary winding respectively, if the
Two differences of two secondary windings are greater than the second preset value of second secondary winding, then verification result is that second secondary winding is not sent out
Raw short circuit.
5. detection verification method according to claim 4, it is characterised in that:
The measurement electrical parameter includes the voltage parameter for measuring the first secondary winding and second secondary winding, using battery and voltage
Table is connected respectively the winding terminal in the first secondary winding and second secondary winding, checks voltage by battery and voltmeter method
The secondary circuit of mutual inductor whether there is short trouble.
6. detection verification method according to claim 4, it is characterised in that:
The measurement voltage parameter for obtaining first secondary winding includes following processing: voltmeter is connected to the first secondary winding
Both ends, one end of battery connects one end of second secondary winding, and the other end of battery overlaps the other end of second secondary winding,
The voltmeter throw of pointer situation for reading the first secondary winding of connection during the lapping process obtains the measurement electricity of the first secondary winding
Press parameter；
The measurement voltage parameter for obtaining the second secondary winding includes following processing: voltmeter is connected to second secondary winding
Both ends, one end of battery connects one end of the first secondary winding, and the other end of battery overlaps the other end of the first secondary winding,
The voltmeter throw of pointer situation for connecting second secondary winding is read during the lapping process, obtains the measurement electricity of second secondary winding
Press parameter.
7. detection verification method according to claim 6, it is characterised in that:
Carrying out verification process to the measurement voltage parameter of obtained first and second secondary winding includes:
The first or second secondary winding for connecting the voltmeter is shorted respectively, and battery one end is respectively corresponded into overlap joint
In one end of the second or first secondary winding, the first certificate parameter of the first secondary winding, the first secondary winding are respectively obtained
Second certificate parameter of the second certificate parameter, the first certificate parameter of second secondary winding and second secondary winding；
By each certificate parameter be not shorted between measurement voltage parameter be compared, if to be greater than its corresponding second pre- for difference
If value, judges that short circuit does not occur for the first secondary winding and second secondary winding.
8. detection verification method according to claim 3, it is characterised in that:
A winding is connected using inductance measuring meter, measures the inductance parameters of the winding, then inductance measuring meter is connected other one
A winding, to measure the inductance parameters of each winding one by one, will the obtained inductance parameters of measurement and the first preset inductance value into
Row compares, and judges whether corresponding secondary winding occurs short circuit, obtains the judging result of each secondary winding, if short circuit occurs,
Measurement terminates, if short circuit does not occur for judgement, enters verification step.
9. detection verification method according to claim 8, which is characterized in that the inductance parameters of each winding of the measurement with
And the step of verifying corresponding inductance parameters, specifically includes following processing:
Measuring process: secohmmeter is connected to the both ends of the first secondary winding or second secondary winding, and second secondary winding is opened
Road or the first secondary winding, measurement obtains the inductance parameters of the first secondary winding or second secondary winding respectively；
Secohmmeter: being connected the both ends of the first secondary winding or second secondary winding by verification step first, be shorted first it is secondary around
The first secondary winding of secohmmeter or the inductance parameters of second secondary winding are read in the both ends of group or second secondary winding, respectively
Obtain the first secondary winding first verifying inductance parameters, the first secondary winding second verifying inductance parameters, it is second secondary around
First verifying inductance parameters of group and the second verifying inductance parameters of second secondary winding；
By each verifying inductance parameters be not shorted between measurement inductance parameters be compared, if difference be greater than its corresponding the
Two default inductance values judge that short circuit does not occur for the first secondary winding and second secondary winding.
10. according to any detection verification method of claim 5-7, it is characterised in that:
Battery case step is made, is fixed in battery case using 2 section 9V batteries, battery case draws wiring.
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