CN105423908A - Transformer winding deformation live test method and system - Google Patents

Abstract

The invention relates to a transformer winding deformation live test method and system. The method comprises the steps that a sine sweep signal of preset frequency range is injected in a neutral bushing end screen connected with one end of a transformer winding; a first response signal and a second response signal are acquired from a high voltage bushing end screen connected with the other end of the transformer winding, and filtering amplification processing is respectively performed on the first response signal and the second response signal so that a first preprocessing signal and a second preprocessing signal are obtained; the first admittance of the transformer winding corresponding to multiple preset frequencies respectively within the preset frequency range is acquired according to the sine sweep signal and the first preprocessing signal so that a first admittance series is obtained, and similarly a second admittance series is obtained according to the sine sweep signal and the second preprocessing signal; the correlation coefficient and the mean square error of the first admittance series and the second admittance series are calculated; and deformation of the transformer winding is judged according to the correlation coefficient and the mean square error. Transformer winding deformation live testing can be realized, and anti-interference performance is high and sensitivity is high.

Description

Deformation of transformer winding charged test method and system

Technical field

The present invention relates to technical field of electric equipment, particularly relate to a kind of deformation of transformer winding charged test method and system.

Background technology

For ensureing the security that transformer uses, avoiding the generation of major accident, usually needing to carry out deformation detection to Transformer Winding.

At present conventional off-line test method is generally to the method that Transformer Winding carries out deformation detection.Off-line test needs the process that has a power failure, and remove all wiring of bushing shell for transformer, the test duration is long, needs the manpower and materials of at substantial, and the test deformation of transformer winding that has a power failure affects by on-the-spot noise, and be difficult to obtain useful signal, measurement sensitivity is low.

Summary of the invention

Based on this, be necessary for the problems referred to above, provide a kind of and can realize live testing and the high deformation of transformer winding charged test method of measurement sensitivity and system.

A kind of deformation of transformer winding charged test method, comprises the steps:

Neutral bushing end shield to connection transformer winding one end injects the sine sweep signal of predeterminated frequency scope;

The first response signal and the second response signal is collected from the end shield of high-voltage bushing connecting the described Transformer Winding other end, and respectively filter amplifying processing is carried out to described first response signal and described second response signal, obtain the first preprocessed signal and the second preprocessed signal;

According to described sine sweep signal and described first preprocessed signal, obtain the first admittance of the described Transformer Winding of the multiple predeterminated frequencies difference correspondences within the scope of described predeterminated frequency, obtain the first admittance ordered series of numbers;

According to described sine sweep signal and described second preprocessed signal, obtain the second admittance of each predeterminated frequency described Transformer Winding corresponding respectively, obtain the second admittance ordered series of numbers;

Calculate related coefficient and the mean square deviation of described first admittance ordered series of numbers and described second admittance ordered series of numbers, differentiate whether described Transformer Winding is out of shape according to described related coefficient and described mean square deviation.

A kind of deformation of transformer winding live testing system, comprise signal generation apparatus, the first protection circuit, signal pickup assembly, signal regulating device and signal processing apparatus, the neutral bushing end shield that described first protection circuit connects described signal generation apparatus respectively and is connected with Transformer Winding one end, the end shield of high-voltage bushing that described signal pickup assembly connects described signal regulating device respectively and is connected with the described Transformer Winding other end, signal processing apparatus connects described signal regulating device and described signal generation apparatus;

Signal generation apparatus generates the sine sweep signal of preset range and exports described first protection circuit and described signal processing apparatus to;

Described first protection circuit is by neutral bushing end shield described in described sine sweep signal injection, and described signal pickup assembly collects the first response signal and the second response signal from described end shield of high-voltage bushing, and exports described signal regulating device to;

Described signal regulating device carries out filter amplifying processing to described first response signal and the second response signal respectively, obtains the first preprocessed signal and the second preprocessed signal and exports described signal processing apparatus to;

Described signal processing apparatus is according to described sine sweep signal and described first preprocessed signal, obtain the first admittance of the described Transformer Winding of the multiple predeterminated frequencies difference correspondences within the scope of described predeterminated frequency, obtain the first admittance ordered series of numbers, according to described sine sweep signal and described second preprocessed signal, obtain the second admittance of each predeterminated frequency described Transformer Winding corresponding respectively, obtain the second admittance ordered series of numbers, calculate related coefficient and the mean square deviation of described first admittance ordered series of numbers and described second admittance ordered series of numbers, differentiate whether described Transformer Winding is out of shape according to described related coefficient and described mean square deviation.

Above-mentioned deformation of transformer winding method of testing and system, by injecting sine sweep signal to Transformer Winding one end, the first response signal and the second response signal is gathered at the Transformer Winding other end, the first preprocessed signal and the second preprocessed signal is obtained after filter and amplification is carried out to the first response signal and the second response signal, then data analysis is carried out to the first preprocessed signal and the second preprocessed signal, analytic process is: the first admittance of the Transformer Winding that the multiple predeterminated frequencies that can obtain respectively within the scope of predeterminated frequency according to sine sweep signal and the first preprocessed signal and the second preprocessed signal are corresponding respectively and the second admittance, obtain the first admittance ordered series of numbers and the second admittance ordered series of numbers, and calculate related coefficient and the mean square deviation of the first admittance ordered series of numbers and the second admittance ordered series of numbers, then judge whether Transformer Winding is out of shape according to related coefficient and mean square deviation.The present invention can be implemented in the uninterrupted power test to deformation of transformer winding under running state of transformer, and test is simple, strong interference immunity and highly sensitive.

Accompanying drawing explanation

Fig. 1 is the process flow diagram of deformation of transformer winding method of testing of the present invention in an embodiment;

Fig. 2 differentiates according to related coefficient and mean square deviation the process flow diagram whether Transformer Winding is out of shape in one embodiment;

Fig. 3 is the structural drawing of deformation of transformer winding test macro of the present invention in an embodiment;

Fig. 4 is the circuit diagram of the first protection circuit in an embodiment;

Fig. 5 is the structural drawing of neutral bushing end shield.

Embodiment

Wherein in an embodiment, with reference to figure 1, the deformation of transformer winding charged test method in one embodiment of the invention, comprises the steps.

S110: the neutral bushing end shield to connection transformer winding one end injects the sine sweep signal of predeterminated frequency scope.

Predeterminated frequency scope specifically can be arranged according to actual conditions, and such as, in the present embodiment, predeterminated frequency scope is 2K-2M hertz.The signal that the frequency that refers to sine sweep signal scans in time within the specific limits repeatedly.In the present embodiment, sine sweep signal is the sinusoidal signal that frequency repeatedly scans in time within the scope of 2K-2M hertz.

Sine sweep signal is injected to neutral bushing end shield, can be that continuation injects identical sine sweep signal, also can be that sine sweep signal is successively injected in interval with preset duration, such as first time re-injects same sine sweep signal after injecting sine sweep signal a period of time.Wherein, preset duration is greater than the frequency sweep cycle of sine sweep signal.

S130: collect the first response signal and the second response signal from the end shield of high-voltage bushing of the connection transformer winding other end, and respectively filter amplifying processing is carried out to the first response signal and the second response signal, obtain the first preprocessed signal and the second preprocessed signal.

Wherein, the collection of the first response signal and the second response signal is synchronous with the sine sweep signal that different time injects.Be specially, from the response signal of corresponding first the sine sweep signal of end shield of high-voltage bushing synchronous acquisition, obtain the first response signal, and then the response signal of the sine sweep signal of synchronous acquisition next one injection, obtain the second response signal.

The time that sweep sine is injected through Transformer Winding from neutral point bottom shielding of bushing is different, and the response signal gathered from end shield of high-voltage bushing may be different.Therefore, the first response signal of collection and the second response signal can reflect that Transformer Winding responds the difference of the sine sweep signal that interval is injected.

By carrying out filter amplifying processing to the first response signal and the second response signal, only can extract signal corresponding with the frequency of sine sweep signal in the first response signal and the second response signal, the anti-interference of signal to noise ratio (S/N ratio) and signal can be improved.

S150: according to sine sweep signal and the first preprocessed signal, obtains the first admittance of the Transformer Winding of the multiple predeterminated frequencies difference correspondences within the scope of predeterminated frequency, obtains the first admittance ordered series of numbers.

Wherein in an embodiment, step S150 is specially:

$Y\left(f\right)=\frac{I_{out}\left(f\right)}{V_{in}\left(f\right)};$

Wherein, f is predeterminated frequency, and Y (f) is the first admittance of Transformer Winding corresponding to f, I _outbe the electric current of the corresponding f of the first preprocessed signal, V _infor the voltage of the corresponding f of sine sweep signal.

Multiple predeterminated frequency can form predeterminated frequency sequence, and the value of predeterminated frequency and number specifically can be arranged according to actual conditions.Such as, in the present embodiment, predeterminated frequency is from the arithmetic sequence of value between 2K-2M, and first predeterminated frequency is 2K hertz (HZ), last predeterminated frequency 2M hertz, difference between adjacent predeterminated frequency is 2KHZ, that is, f=2KHZ, 4KHZ, 6KHZ ... 2MHZ, the total number of predeterminated frequency is 1000.

By calculating the first admittance, the ratio relation of the electric current of the first preprocessed signal that each predeterminated frequency is corresponding and the voltage of sine sweep signal can be reflected.

S170: according to sine sweep signal and the second preprocessed signal, obtains the second admittance of each predeterminated frequency Transformer Winding corresponding respectively, obtains the second admittance ordered series of numbers.

In the present embodiment, the calculating of the second admittance and the compute classes of the first admittance seemingly, do not repeat at this.

According to related coefficient and mean square deviation, S190: the related coefficient and the mean square deviation that calculate the first admittance ordered series of numbers and the second admittance ordered series of numbers, differentiates whether Transformer Winding is out of shape.

Wherein in an embodiment, calculate related coefficient and the mean square deviation of the first admittance ordered series of numbers and the second admittance ordered series of numbers in step S190, be specially:

$D_X=\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}{\[X\left(k\right)-\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}X\left(k\right)\]}^2,D_Y=\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}{\[Y\left(k\right)-\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}Y\left(k\right)\]}^2,k=0,1,\mathrm{...}N-1;$

$C_{XY}=\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}{\[X\left(k\right)-\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}X\left(k\right)\]}^2\·\[Y\left(K\right)-\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}Y\left(k\right)\];$

${\mathrm{LR}}_{XY}=C_{XY}/\sqrt{D_X{D}_Y};$

$R_{XY}=\left\{\begin{array}{c}10\\ -lg(1-L{R}_{XY})\end{array}\right\};$

$E_{XY}=\sqrt{\underset{k=0}{\overset{N-1}{\Σ}}{\left(X\right(k)-Y(k\left)\right)}^2/N};$

Wherein, N is total number of predeterminated frequency, and k is the sequence number of predeterminated frequency, and X (k) is the first admittance ordered series of numbers, and Y (k) is the second admittance ordered series of numbers, D _xbe the standard variance of the first admittance ordered series of numbers, D _ybe the standard variance of the second admittance ordered series of numbers, C _xYbe the covariance of the first admittance ordered series of numbers and the second admittance ordered series of numbers, LR _xYbe the normalized covariance coefficient of the first admittance ordered series of numbers and the second admittance ordered series of numbers, R _xYfor related coefficient, E _xYfor mean square deviation.

According to the covariance of the standard variance of the first admittance ordered series of numbers, the standard variance of the second admittance ordered series of numbers and the first admittance ordered series of numbers and the second admittance ordered series of numbers, the normalized covariance coefficient of the first admittance ordered series of numbers and the second admittance ordered series of numbers can be calculated, and obtain the related coefficient of the first admittance ordered series of numbers and the second admittance ordered series of numbers according to normalization variance.The mean square deviation of the first admittance ordered series of numbers and the second admittance ordered series of numbers can be obtained according to the standard variance of the first admittance ordered series of numbers, the standard variance of the second admittance ordered series of numbers.Particularly, in the present embodiment, N=1000.

Wherein in an embodiment, with reference to figure 2, in step S190, differentiate whether Transformer Winding is out of shape, and comprises step S191 to step S193 according to related coefficient and mean square deviation.

S191: the absolute value judging mean square deviation whether within the scope of default variance and the absolute value of related coefficient within the scope of preset correlation coefficient number.If so, then perform step S192, if not, then perform step S193.

S192: judge that Transformer Winding is not out of shape.

S193: judge deformation of transformer winding.

Default variance scope and preset correlation coefficient number scope specifically can be arranged according to actual conditions.Such as, in the present embodiment, default variance scope can be the scope close to 0, and preset correlation coefficient number scope can be the scope close to 1.When the absolute value of mean square deviation is within the scope of default variance, the Article 2 curve that the Article 1 curve that expression transverse axis is frequency, the longitudinal axis is the first admittance and transverse axis are frequency, the longitudinal axis is the second admittance is very close; When the absolute value of related coefficient is within the scope of preset correlation coefficient number, the Article 2 curvilinear correlation degree that the Article 1 curve that expression transverse axis is frequency, the longitudinal axis is the first admittance and transverse axis are frequency, the longitudinal axis is the second admittance is very high.When comprehensively meeting this two situations, represent the first response signal and the second response signal difference less, thus can judge that Transformer Winding is not out of shape.The present invention can be implemented in the uninterrupted power test to deformation of transformer winding under running state of transformer, and without the need to having a power failure process and strong interference immunity, test is simple and accuracy is high.

Above-mentioned deformation of transformer winding band point method of testing, by injecting sine sweep signal to Transformer Winding one end, the first response signal and the second response signal is gathered at the Transformer Winding other end, the first preprocessed signal and the second preprocessed signal is obtained after filter and amplification is carried out to the first response signal and the second response signal, then data analysis is carried out to the first preprocessed signal and the second preprocessed signal, analytic process is: the first admittance of the Transformer Winding that the multiple predeterminated frequencies that can obtain respectively within the scope of predeterminated frequency according to sine sweep signal and the first preprocessed signal and the second preprocessed signal are corresponding respectively or the second admittance, obtain the first admittance ordered series of numbers and the second admittance ordered series of numbers, calculate related coefficient and the mean square deviation of the first admittance ordered series of numbers and the second admittance ordered series of numbers, then judge whether Transformer Winding is out of shape according to related coefficient and mean square deviation.The present invention can be implemented in the uninterrupted power test to deformation of transformer winding under running state of transformer, without the need to having a power failure process and strong interference immunity, tests simple and highly sensitive.

With reference to figure 3, the deformation of transformer winding live testing system in one embodiment of the invention, comprises signal generation apparatus 110, first protection circuit 130, signal pickup assembly 150, signal regulating device 170 and signal processing apparatus 190.First protection circuit 130 difference connection signal generating means 110 and the neutral bushing end shield 201 be connected with Transformer Winding 200 one end; signal pickup assembly 150 difference connection signal conditioning device 170 and the end shield of high-voltage bushing 203 be connected with Transformer Winding 200 other end, signal processing apparatus 190 connection signal conditioning device 170 and signal generation apparatus 110.

Signal generation apparatus 110 generates the sine sweep signal of preset range and exports the first protection circuit 130 and signal processing apparatus 190 to.Wherein, predeterminated frequency scope specifically can be arranged according to actual conditions, and such as, in the present embodiment, predeterminated frequency scope is 2K-2M hertz.The signal that the frequency that refers to sine sweep signal scans in time within the specific limits repeatedly.In the present embodiment, sine sweep signal is the sinusoidal signal that frequency repeatedly scans in time within the scope of 2K-2M hertz.

First protection circuit 130 is by sine sweep signal injection neutral bushing end shield 201.First protection circuit 130 injects sine sweep signal to neutral bushing end shield; can be that continuation injects identical sine sweep signal; also can be that sine sweep signal is successively injected in interval with preset duration; such as first time re-injects same sine sweep signal after injecting sine sweep signal a period of time.Wherein, preset duration is greater than the frequency sweep cycle of sine sweep signal.

Signal pickup assembly 150 collects the first response signal and the second response signal from end shield of high-voltage bushing 203, and exports signal regulating device 170 to.Wherein, the collection of the first response signal and the second response signal is synchronous with the sine sweep signal that different time injects.Be specially, from the response signal of corresponding first the sine sweep signal of end shield of high-voltage bushing synchronous acquisition, obtain the first response signal, and then the response signal of the sine sweep signal of synchronous acquisition next one injection, obtain the second response signal.

The time that sweep sine is injected through Transformer Winding from neutral point bottom shielding of bushing is different, and the response signal gathered from end shield of high-voltage bushing may be different.Therefore, signal pickup assembly 150 gather the first response signal and the second response signal can reflect that Transformer Winding responds the difference of the sine sweep signal that interval is injected.

Signal regulating device 170 carries out filter amplifying processing to the first response signal and the second response signal respectively, obtains the first preprocessed signal and the second preprocessed signal and exports signal processing apparatus 190 to.By carrying out filter amplifying processing to the first response signal and the second response signal, only can extract signal corresponding with the frequency of sine sweep signal in the first response signal and the second response signal, the anti-interference of signal to noise ratio (S/N ratio) and signal can be improved.

Signal processing apparatus 190, according to sine sweep signal and the first preprocessed signal, obtains the first admittance of the Transformer Winding of the multiple predeterminated frequencies difference correspondences within the scope of predeterminated frequency, obtains the first admittance ordered series of numbers.Signal processing apparatus 190, according to sine sweep signal and the second preprocessed signal, obtains the second admittance of each predeterminated frequency Transformer Winding corresponding respectively, obtains the second admittance ordered series of numbers.Signal processing apparatus 190 calculates the first admittance ordered series of numbers and the second admittance ordered series of numbers obtains related coefficient and mean square deviation, differentiates whether Transformer Winding is out of shape according to related coefficient and mean square deviation.

Above-mentioned deformation of transformer winding test macro, generate the sine sweep signal of predeterminated frequency scope by signal generation apparatus 110 and export the first protection circuit 130 and signal processing apparatus 190 to, first protection circuit 130 injects sine sweep signal to Transformer Winding one end, signal pickup assembly 150 collects the first response signal and the second response signal at the Transformer Winding other end, signal regulating device 170 obtains the first preprocessed signal and the second preprocessed signal after carrying out filtering process to the first response signal and the second response signal, then signal processing apparatus 190 carries out data analysis to the first preprocessed signal and the second preprocessed signal, analytic process is: the first admittance of the Transformer Winding that the multiple predeterminated frequencies that can obtain respectively within the scope of predeterminated frequency according to sine sweep signal and the first preprocessed signal and the second preprocessed signal are corresponding respectively and the second admittance, obtain the first admittance ordered series of numbers and the second admittance ordered series of numbers, signal processing apparatus 190 calculates the first admittance ordered series of numbers and the second admittance ordered series of numbers obtains related coefficient and mean square deviation, can judge that transverse axis is frequency according to the related coefficient of trying to achieve, the longitudinal axis is the Article 1 curve of the first admittance number and transverse axis is frequency, the longitudinal axis is the degree of correlation between the Article 2 curve of the second admittance ordered series of numbers, according to the mean square deviation of trying to achieve can judge Article 1 curve and Article 2 curve whether close, therefore, the variation relation that can judge between the first response signal and the second response signal by related coefficient and mean square deviation, thus judge whether Transformer Winding is out of shape.The present invention can be implemented in the uninterrupted power test to deformation of transformer winding under running state of transformer, without the need to having a power failure process and strong interference immunity, tests simple and highly sensitive.

Wherein in an embodiment; with reference to figure 3; signal generation apparatus 110 comprises sweep generator 111 and RC divider 113, and sweep generator 111 connects RC divider 113 and the first protection circuit 130, RC divider 113 connection signal treating apparatus 190.Sweep generator 111 generates sine sweep signal and exports the first protection circuit 130 and RC divider 113 one end to, and the sine sweep signal after RC divider 113 other end output buck is to signal processing apparatus 190.

In the present embodiment, signal generator 111 is fixed on transformer-cabinet outer wall.The voltage of sine sweep signal can be down in the upper voltage limit value that signal processing apparatus 190 can receive by RC divider 113.Such as, in the present embodiment, for improving signal to noise ratio (S/N ratio), the voltage of the sine sweep signal that signal generation apparatus 110 exports reaches 200VPP (VoltagePeak-Peak peak-to-peak value voltage), the upper voltage limit of signal processing apparatus 190 is 10V, within sine sweep signal is down to 10V by RC divider 113.

Particularly, in the present embodiment, sweep generator 111 can receive wireless control signal, and exports needlework swept-frequency signal to the first protection circuit 130 and RC divider 113 according to wireless control signal.By the wireless trigger mode of sweep generator 111, the synchronized sampling of signal injection and collection can be realized, improve the data precision.In the present embodiment, signal processing apparatus 190 wireless connections sweep generator 111, signal processing apparatus 190 can export wireless control signal to sweep generator 111, also can arrange the Frequency point of sinusoidal signal, the mode of operation etc. of sweep generator.Be appreciated that in other embodiments, wireless control signal also can be sent to sweep generator 111 by other means, such as, can be that tester sends by using intelligent terminal.

Wherein in an embodiment, with reference to figure 4 and Fig. 5, the first protection circuit 130 comprises gas-discharge tube SP, inductance L and voltage dependent resistor (VDR) R.Ground capacitance C2 when electric capacity C1 between neutral bushing with neutral bushing end shield 201 opens a way with neutral bushing end shield connects, the electric capacity C1 other end between neutral bushing with neutral bushing end shield 201 is connected neutral bushing end shield 201, ground capacitance C2 other end ground connection during neutral bushing end shield open circuit.One end of gas-discharge tube SP connects sweep generator 111, other end ground connection, inductance L is in parallel with voltage dependent resistor (VDR) R, and one end after parallel connection connects the common port that ground capacitance C2 when common port that sweep generator 111 is connected with gas-discharge tube SP and the electric capacity C1 between neutral bushing with neutral bushing end shield 201 open a way with neutral bushing end shield is connected, the other end ground connection after inductance L is in parallel with voltage dependent resistor (VDR) R.

Transformer neutral point unbalance voltage is general very little, but end shield of high-voltage bushing voltage can reach more than 10kV.The effect of the first protection circuit 130 mainly prevents singlephase earth fault from causing neutral point voltage sharply to raise and threatens the personal safety of tester and the safe operation of equipment.First protection circuit 130 is made up of inductance L, voltage dependent resistor (VDR) R and gas-discharge tube SP.Neutral bushing is condenser-type terminal; it is generally layered structure; electric capacity C1 between neutral bushing and neutral bushing end shield and the ground capacitance C2 of neutral bushing end shield forms capacitive divider; add that the impact of shunt inductance L in the first protection circuit 130 can make the power-frequency voltage of neutral bushing end shield be reduced to below 10V, relay testing personnel and device security.When voltage dependent resistor (VDR) R is certain in temperature, voltage increases, resistivity can sharply reduce, and when voltage reaches its sparking voltage, first voltage dependent resistor (VDR) R discharges, and reaches the object to equipment protection.Gas-discharge tube SP forms with the band gap metal electrode of inert gas by filling; when both end voltage reaches the voltage breakdown of gas-discharge tube SP; gas-discharge tube SP just starts electric discharge; and become Low ESR by high impedance; two electrode proximate short circuits; thus by superpotential bypass, achieve the protection to equipment and tester.First protection circuit 130 transient suppression superpotential, for the back-up protection of injection circuit.

Wherein in an embodiment; with reference to figure 3; signal pickup assembly 150 comprises the second protection circuit 151 and HF current transformer 153; second protection circuit 151 one end connects high-pressure side bottom shielding of bushing 203; the other end passes the rear ground connection of HF current transformer 153, the output terminal connection signal conditioning device 170 of HF current transformer 153.

In the present embodiment, HF current transformer 153 is ring punching structure, and second protection circuit 151 one end gathers the first output signal and second output signal of end shield of high-voltage bushing 203, and the other end is through ground connection after HF current transformer 153.HF current transformer 153 is responded to the first output signal and second and is outputed signal the first response signal and the second response signal that obtain corresponding sine sweep signal, and exports the first response signal and the second response signal to signal regulating device 170.

The circuit structure of the second protection circuit 151 can be identical with the circuit structure of the first protection circuit 130, do not repeat at this.The safeguard protection of equipment to collection terminal and tester can be realized by the second protection circuit 151.

In the present embodiment, HF current transformer 153 adopts Pearson 4100 model, and output impedance is 50 Ω, and peak inrush current is 500A, maximum effective value electric current 5A, and available rising time 5ns, test frequency scope 140Hz-35MHz, output terminal is bnc interface.

Wherein in an embodiment, with reference to figure 3, signal regulating device 170 comprises RC wave filter 171 and signal amplifier 173, RC wave filter 171 connection signal harvester 150 and signal amplifier 173, signal amplifier 173 connection signal treating apparatus 190.RC wave filter 171 receives the first response signal and the second response signal and carries out filtering process to the first response signal and the second response signal, obtains the first filtering signal and the second filtering signal and exports signal amplifier 173 to.Signal amplifier 173 carries out amplification process to the first filtering signal and the second filtering signal, obtains the first preprocessed signal and the second preprocessed signal and exports signal processing apparatus 190 to.By RC wave filter 171, filtering process is carried out to the first response signal and the second response signal, improve accuracy and the anti-interference of follow-up data process.By signal amplifier 173, amplification process is carried out to the first filtering signal and the second filtering signal, be convenient to reception and the data analysis operation of signal processing apparatus 190.

Wherein in an embodiment, signal processing apparatus 190 basis:

$Y\left(f\right)=\frac{I_{out}\left(f\right)}{V_{in}\left(f\right)};$

Calculate the first admittance of the Transformer Winding of the multiple predeterminated frequencies difference correspondences within the scope of predeterminated frequency.Wherein, f is predeterminated frequency, and Y (f) is the first admittance of Transformer Winding corresponding to f, I _outbe the electric current of the corresponding f of the first preprocessed signal, V _infor the voltage of the corresponding f of sine sweep signal.

Multiple predeterminated frequency can form predeterminated frequency sequence, and the value of predeterminated frequency and number specifically can be arranged according to actual conditions.Such as, in the present embodiment, predeterminated frequency is from the arithmetic sequence of value between 2K-2M, and first predeterminated frequency is 2K hertz (HZ), last predeterminated frequency 2M hertz, difference between adjacent predeterminated frequency is 2KHZ, that is, f=2KHZ, 4KHZ, 6KHZ ... 2MHZ, the total number of predeterminated frequency is 1000.

By calculating the first admittance, the ratio relation of the electric current of the first preprocessed signal that each predeterminated frequency is corresponding and the voltage of sine sweep signal can be reflected.In the present embodiment, the calculating of the second admittance and the compute classes of the first admittance seemingly, do not repeat at this.

Wherein in an embodiment, signal processing apparatus 190 can basis:

$D_X=\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}{\[X\left(k\right)-\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}X\left(k\right)\]}^2,D_Y=\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}{\[Y\left(k\right)-\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}Y\left(k\right)\]}^2,k=0,1,...N-1;$

$C_{XY}=\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}{\[X\left(k\right)-\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}X\left(k\right)\]}^2\·\[Y\left(K\right)-\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}Y\left(k\right)\];$

${\mathrm{LR}}_{XY}=C_{XY}/\sqrt{D_X{D}_Y};$

$R_{XY}=\left\{\begin{array}{c}10\\ -lg(1-L{R}_{XY})\end{array}\right\};$

$E_{XY}=\sqrt{\underset{k=0}{\overset{N-1}{\Σ}}{\left(X\right(k)-Y(k\left)\right)}^2/N};$

Calculate related coefficient and the mean square deviation of the first admittance and the second admittance.Wherein, N is total number of predeterminated frequency, and k is the sequence number of predeterminated frequency, and X (k) is the first admittance ordered series of numbers, and Y (k) is the second admittance ordered series of numbers, D _xbe the standard variance of the first admittance ordered series of numbers, D _ybe the standard variance of the second admittance ordered series of numbers, C _xYbe the covariance of the first admittance ordered series of numbers and the second admittance ordered series of numbers, LR _xYbe the normalized covariance coefficient of the first admittance ordered series of numbers and the second admittance ordered series of numbers, R _xYfor related coefficient, E _xYfor mean square deviation.

According to the covariance of the standard variance of the first admittance ordered series of numbers, the standard variance of the second admittance ordered series of numbers and the first admittance ordered series of numbers and the second admittance ordered series of numbers, the normalized covariance coefficient of the first admittance ordered series of numbers and the second admittance ordered series of numbers can be calculated, and obtain the related coefficient of the first admittance ordered series of numbers and the second admittance ordered series of numbers according to normalization variance.The mean square deviation of the first admittance ordered series of numbers and the second admittance ordered series of numbers can be obtained according to the standard variance of the first admittance ordered series of numbers, the standard variance of the second admittance ordered series of numbers.Particularly, in the present embodiment, N=1000.

Wherein in an embodiment, the absolute value that signal processing apparatus 190 can judge mean square deviation whether within the scope of default variance and the absolute value of related coefficient within the scope of preset correlation coefficient number.If so, then judge that Transformer Winding is not out of shape; If not, then deformation of transformer winding is judged.Default variance scope and preset correlation coefficient number scope specifically can be arranged according to actual conditions.Such as, in the present embodiment, default variance scope can be the scope close to 0, and preset correlation coefficient number scope can be the scope close to 1.When the absolute value of mean square deviation is within the scope of default variance, the Article 2 curve that the Article 1 curve that expression transverse axis is frequency, the longitudinal axis is the first admittance and transverse axis are frequency, the longitudinal axis is the second admittance is very close; When the absolute value of related coefficient is within the scope of preset correlation coefficient number, the Article 2 curvilinear correlation degree that the Article 1 curve that expression transverse axis is frequency, the longitudinal axis is the first admittance and transverse axis are frequency, the longitudinal axis is the second admittance is very high.When comprehensively meeting this two situations, represent the first response signal and the second response signal difference less, thus can judge that Transformer Winding is not out of shape.The present invention can be implemented in the uninterrupted power test to deformation of transformer winding under running state of transformer, and without the need to having a power failure process and strong interference immunity, test is simple and accuracy is high.

Wherein in an embodiment, signal processing apparatus 190 comprises capture card (not shown) and industrial computer 191, and capture card is connection signal generating means 110, signal regulating device 170 and industrial computer 191 respectively.

Capture card receives sine sweep signal, the first preprocessed signal and the second preprocessed signal and is forwarded to industrial computer 191.Particularly, with reference to figure 3, the acquisition channel of capture card comprises data acquisition channel 0 and data acquisition channel 1, data acquisition channel 0 connection signal generating means 110 and industrial computer 191, data acquisition channel 1 connection signal conditioning device 170 and industrial computer 191.In the present embodiment, capture card adopts Ling Hua PCIe-9852 type, can realize the signals collecting of 200MS/s while of two passages.

Industrial computer 191 is according to sine sweep signal and the first corresponding preprocessed signal, obtain the first admittance of the Transformer Winding of the multiple predeterminated frequencies difference correspondences within the scope of predeterminated frequency, obtain the first admittance ordered series of numbers, according to sine sweep signal and the second corresponding preprocessed signal, obtain the second admittance of each predeterminated frequency Transformer Winding corresponding respectively, obtain the second admittance ordered series of numbers.Industrial computer 191 calculates related coefficient and the mean square deviation of the first admittance ordered series of numbers and the second admittance ordered series of numbers according to the first admittance ordered series of numbers and the second admittance ordered series of numbers, differentiates whether Transformer Winding is out of shape according to related coefficient and mean square deviation.

Be appreciated that in other examples, the equipment that other also can be adopted can to realize data processing and analysis replaces industrial computer 191.

Each technical characteristic of the above embodiment can combine arbitrarily, for making description succinct, the all possible combination of each technical characteristic in above-described embodiment is not all described, but, as long as the combination of these technical characteristics does not exist contradiction, be all considered to be the scope that this instructions is recorded.

The above embodiment only have expressed several embodiment of the present invention, and it describes comparatively concrete and detailed, but can not therefore be construed as limiting the scope of the patent.It should be pointed out that for the person of ordinary skill of the art, without departing from the inventive concept of the premise, can also make some distortion and improvement, these all belong to protection scope of the present invention.Therefore, the protection domain of patent of the present invention should be as the criterion with claims.

Claims (10)

1. a deformation of transformer winding charged test method, is characterized in that, comprises the steps:

Neutral bushing end shield to connection transformer winding one end injects the sine sweep signal of predeterminated frequency scope;

The first response signal and the second response signal is collected from the end shield of high-voltage bushing connecting the described Transformer Winding other end, and respectively filter amplifying processing is carried out to described first response signal and described second response signal, obtain the first preprocessed signal and the second preprocessed signal;

According to described sine sweep signal and described first preprocessed signal, obtain the first admittance of the described Transformer Winding of the multiple predeterminated frequencies difference correspondences within the scope of described predeterminated frequency, obtain the first admittance ordered series of numbers;

According to described sine sweep signal and described second preprocessed signal, obtain the second admittance of each predeterminated frequency described Transformer Winding corresponding respectively, obtain the second admittance ordered series of numbers;

Calculate related coefficient and the mean square deviation of described first admittance ordered series of numbers and described second admittance ordered series of numbers, differentiate whether described Transformer Winding is out of shape according to described related coefficient and described mean square deviation.

2. deformation of transformer winding charged test method according to claim 1, it is characterized in that, described according to described sine sweep signal and described first preprocessed signal, obtain the first admittance of the described Transformer Winding of the multiple predeterminated frequencies difference correspondences within the scope of described predeterminated frequency, be specially:

$Y\left(f\right)=\frac{I_{out}\left(f\right)}{V_{in}\left(f\right)};$

Wherein, f is predeterminated frequency, and Y (f) is the first admittance of Transformer Winding corresponding to f, I _outfor the electric current of the corresponding f of described first preprocessed signal, V _infor the voltage of the corresponding f of described sine sweep signal.

3. deformation of transformer winding charged test method according to claim 1, is characterized in that, the related coefficient of the described first admittance ordered series of numbers of described calculating and described second admittance ordered series of numbers and mean square deviation, be specially:

$D_X=\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}{\[X\left(k\right)-\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}X\left(k\right)\]}^2,D_Y=\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}{\[Y\left(k\right)-\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}Y\left(k\right)\]}^2,k=0,1,...N-1;$

$C_{XY}=\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}{\[X\left(k\right)-\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}X\left(k\right)\]}^2\·\[Y\left(K\right)-\frac{1}{N}\underset{k=0}{\overset{N-1}{\Σ}}Y\left(k\right)\];$

${\mathrm{LR}}_{XY}=C_{XY}/\sqrt{D_X{D}_Y};$

$R_{XY}=\left\{\begin{array}{c}10\\ -\lg (1-{\mathrm{LR}}_{XY})\end{array}\right\};$

$E_{XY}=\sqrt{\underset{k=0}{\overset{N-1}{\Σ}}{\left(X\right(k)-Y(k\left)\right)}^2/N};$

Wherein, N is total number of described predeterminated frequency, and k is the sequence number of described predeterminated frequency, and X (k) is described first admittance ordered series of numbers, and Y (k) is described second admittance ordered series of numbers, D _xfor the standard variance of described first admittance ordered series of numbers, D _yfor the standard variance of described second admittance ordered series of numbers, C _xYfor the covariance of described first admittance ordered series of numbers and described second admittance ordered series of numbers, LR _xYfor the normalized covariance coefficient of described first admittance ordered series of numbers and described second admittance ordered series of numbers, R _xYfor described related coefficient, E _xYfor described mean square deviation.

4. deformation of transformer winding charged test method according to claim 1, is characterized in that, describedly differentiates whether described Transformer Winding is out of shape, and comprising according to described related coefficient and described mean square deviation:

The absolute value judging described mean square deviation whether within the scope of default variance and the absolute value of described related coefficient within the scope of preset correlation coefficient number;

If so, then judge that described Transformer Winding is not out of shape;

If not, then described deformation of transformer winding is judged.

5. a deformation of transformer winding live testing system, it is characterized in that, comprise signal generation apparatus, the first protection circuit, signal pickup assembly, signal regulating device and signal processing apparatus, the neutral bushing end shield that described first protection circuit connects described signal generation apparatus respectively and is connected with Transformer Winding one end, the end shield of high-voltage bushing that described signal pickup assembly connects described signal regulating device respectively and is connected with the described Transformer Winding other end, signal processing apparatus connects described signal regulating device and described signal generation apparatus;

Signal generation apparatus generates the sine sweep signal of preset range and exports described first protection circuit and described signal processing apparatus to;

Described first protection circuit is by neutral bushing end shield described in described sine sweep signal injection, and described signal pickup assembly collects the first response signal and the second response signal from described end shield of high-voltage bushing, and exports described signal regulating device to;

Described signal regulating device carries out filter amplifying processing to described first response signal and the second response signal respectively, obtains the first preprocessed signal and the second preprocessed signal and exports described signal processing apparatus to;

Described signal processing apparatus is according to described sine sweep signal and described first preprocessed signal, obtain the first admittance of the described Transformer Winding of the multiple predeterminated frequencies difference correspondences within the scope of described predeterminated frequency, obtain the first admittance ordered series of numbers, according to described sine sweep signal and described second preprocessed signal, obtain the second admittance of each predeterminated frequency described Transformer Winding corresponding respectively, obtain the second admittance ordered series of numbers, calculate related coefficient and the mean square deviation of described first admittance ordered series of numbers and described second admittance ordered series of numbers, differentiate whether described Transformer Winding is out of shape according to described related coefficient and described mean square deviation.

6. deformation of transformer winding live testing system according to claim 5; it is characterized in that; described signal generation apparatus comprises sweep generator and RC divider; described sweep generator connects described RC divider and described first protection circuit, and described RC divider connects described signal processing apparatus.

7. deformation of transformer winding live testing system according to claim 5; it is characterized in that; described first protection circuit comprises gas-discharge tube, inductance and voltage dependent resistor (VDR); ground capacitance when electric capacity between neutral bushing with described neutral bushing end shield is opened a way with described neutral bushing end shield is connected; the electric capacity other end between neutral bushing with described neutral bushing end shield is connected described neutral bushing end shield; ground capacitance other end ground connection during described neutral bushing end shield open circuit

One end of described gas-discharge tube connects described sweep generator, other end ground connection, described inductance is in parallel with described voltage dependent resistor (VDR), and the one end after parallel connection connects the common port that ground capacitance when common port that described sweep generator is connected with described gas-discharge tube and the electric capacity between neutral bushing with described neutral bushing end shield are opened a way with described neutral bushing end shield is connected, the other end ground connection after described inductance is in parallel with described voltage dependent resistor (VDR).

8. deformation of transformer winding live testing equipment according to claim 5; it is characterized in that; described signal pickup assembly comprises HF current transformer and the second protection circuit; described second protection circuit one end connects described high-pressure side bottom shielding of bushing; the other end is through ground connection after described HF current transformer, and the output terminal of described HF current transformer connects described signal regulating device.

9. deformation of transformer winding live testing equipment according to claim 5, it is characterized in that, described signal regulating device comprises RC wave filter and signal amplifier, described RC wave filter connects described signal pickup assembly and described signal amplifier, and described signal amplifier connects described signal processing apparatus.

10. deformation of transformer winding live testing equipment according to claim 5, it is characterized in that, described signal processing apparatus comprises industrial computer and capture card, and described capture card connects described signal generation apparatus, signal regulating device and described industrial computer respectively.