JPH1194897A - Method and device for measuring partial discharge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for measuring partial discharge which occurs during operation of an electrical equipment and also to provide a device wherein a partial discharge is discriminated from a noise occurring during operation of the electrical equipment while partial discharge is measured with precision. SOLUTION: The entire pulse containing partial discharge and noise is detected and digitized, and temporarily saved in a first storage means 30, after that, by accessing the first storage means 30, it is saved in a second storage means 33A, and calculation is performed for each pulse based on the characteristics quantity and signal quantity of the partial discharge and noise, so that signal is discriminated from noise and saved in the second storage means 33A, with a measurement result displayed. Thus, such partial discharge during operation buried in noise is measured with precision. Further, a measurement data may be re-analyzed using a noise separation information obtained later, for improved measurement precision.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for measuring a partial discharge, and more particularly to an apparatus and a method for detecting a partial discharge while a high-voltage rotating electrical machine is stopped or operating.

[0002]

2. Description of the Related Art In recent years, the scale of plants in general industry has been steadily increasing in size. As a result, electric equipment such as rotating electric machines and gas insulation equipment has also increased in size, and the number of installations has also increased. doing. Accordingly, high reliability is required for such an electric device, and it is necessary to reliably perform maintenance and inspection and to prevent sudden accidents such as insulation breakdown.

[0003] In addition, the majority of electrical equipment manufactured during the period of high economic growth has already passed over 25 years, and the majority of these electrical equipment that has been operating for a long time has been designed to prevent sudden accidents. The demand for continuous monitoring during operation has become very strong.

In addition, the Electricity Business Law was revised in fiscal 1996, and efforts were made to extend the interval between regular inspections that had been conventionally performed by about 1.5 times, with the aim of strengthening voluntary security measures through deregulation and improving management efficiency. Has been done. For this reason, the monitoring of the insulation state during operation has become more important than ever, and as a monitoring item thereof, the technique of continuous monitoring of partial discharge showing the insulation properties has been gaining importance. Since a partial discharge of a rotating electrical machine or the like is generally buried in noise, it is necessary to distinguish a partial discharge signal from a noise and measure only the partial discharge. Noise during operation is the biggest factor that makes partial discharge measurement difficult.

[0005] Many methods have conventionally been used for discriminating partial discharge from noise and measuring only partial discharge. For example, in a partial discharge measurement device for a rotating electric machine disclosed in Japanese Patent Application Laid-Open No. 1-116463 shown in FIG. 6, the partial discharge measurement device is placed at a predetermined position of a driving or output lead wire of the rotating electric machine during operation. The voltage wave and the current wave of the partial discharge and noise propagation waves which are provided and propagated through the lead line are detected to determine the polarity, and the propagation of the propagation wave on the lead line is determined based on the determined combination of the polarity of the voltage wave and the current wave. There is disclosed an apparatus configured to determine the direction, distinguish between partial discharge and noise, and detect only partial discharge.

[0006] Japanese Patent Application Laid-Open No. 3-57976 discloses that
A partial discharge sensor designed for partial discharge detection is arranged in the stator slot of the stator winding of a generator, etc., and only the partial discharge generated in the specific stator slot where the partial discharge sensor is installed is limited. A method and an apparatus for performing measurement are disclosed. In this method, since the high-frequency signal is greatly attenuated when propagating in the stator slot, a sensor designed only for the high-frequency signal of 100 MHz or more is sensitive only to the partial discharge in the stator slot. In addition, noise is distinguished by being relatively insensitive to noise.

[0007] Japanese Patent Application Laid-Open No. 4-70573 discloses that
A partial discharge measurement method is disclosed in which a frequency spectrum is obtained for a noise signal, a frequency with low noise is selected from the frequency spectrum, and a partial discharge pulse having a certain level or more detected at this frequency is counted.

Further, in US Pat. No. 5,126,677, a noise sensor is provided at a location where noise is generated and invaded, in combination with a partial discharge sensor, and when a signal is detected by the noise sensor, a signal is output from the partial discharge sensor. A device and a method of controlling the gate of the signal circuit of FIG. 1 to measure only partial discharge are shown.

Japanese Patent Application Laid-Open No. Hei 8-271573 discloses that in the detection of partial discharge of GIS, frequency characteristic data generated in an insulating device is detected and collected at a waveform sampling time capable of detecting only stationary noise. One sweep data is compared with peak hold data collected at a peak hold time at which a partial discharge waveform can be detected,
There is disclosed a detection method for determining whether or not a partial discharge has occurred based on a difference between sweep data and peak hold data. This method also describes a method of extracting an unknown partial discharge waveform based on data learned in advance by using a neural network to determine whether or not a partial discharge has occurred.

Further, various other partial discharge measurement methods and devices are reported in Technical Report II, No. 402 and No. 593 of the Institute of Electrical Engineers of Japan. In this, a partial discharge measurement method and apparatus using a computer are described. They are,
High-precision insulation measurement technology that uses a computer to capture partial discharge pulses, which are high-speed phenomena, and performs computer processing on the frequency, phase, and number of occurrences of many partial discharge pulses measured by a partial discharge measurement device. Is to achieve.

As a typical example of such prior art, FIG.
Shows an example of a partial discharge measurement device for rotating electrical machines,
The configuration and operation of this prior art will be described with reference to FIG. FIG. 6 is a block diagram of the partial discharge measuring device disclosed in the above-mentioned JP-A-1-116463. In FIG. 6, this conventional partial discharge measuring device is provided at a predetermined position of a lead 4 of an induction motor 3 during operation, and a voltage wave and a current of a partial discharge and a noise propagation wave propagating through the lead 4 are shown. A voltage wave detecting circuit 5 and a current amount detecting circuit 6 for detecting each of the waves, and polarity determining circuits 10 and 11 for determining the polarities of the voltage wave and the current wave detected by the voltage wave detecting circuit 5 and the current amount detecting circuit 6, respectively. And a traveling wave traveling direction discriminating circuit 12 for discriminating the traveling direction of the propagating wave on the lead wire 4 from the combination of the voltage wave and the current wave thus determined. It is open in the case of a detected wave of a propagation wave traveling from the tester 3 to the power supply 7 side of the tester 3, and is open for the propagation wave traveling from the power supply 7 side of the tester 3 to the tester 3 side. Gate circuit 8 closed in case of detection wave
And a discharge amount measuring circuit 9 connected to the gate circuit 8 and measuring the partial discharge amount.

Next, the operation of the prior art will be described. A voltage wave and a current wave of a partial discharge and noise propagation wave propagating in the lead wire 4 of the induction motor 3 are detected by a voltage wave detection circuit 5 and a current amount detection circuit 6. Detected voltage wave,
The polarity of the current wave is determined by the polarity determination circuits 10 and 11. The gate circuit 8 determines, based on the combination of the polarities of the voltage wave and the current wave determined by the polarity determination circuits 10 and 11, that the propagation method of the propagation wave proceeds from the test equipment 3 to the power supply 7 side of the test equipment 3. In the case of the detection wave of (1), it is determined that the discharge is partial discharge, and the detection wave is opened. Of the detection waves detected by the voltage wave detection circuit 5, those other than noise are input to the discharge amount measurement circuit 9, and the partial discharge amount is measured.

[0013]

In the above-described conventional partial discharge measuring method and measuring apparatus, the method of progressing the partial discharge and the propagation wave of the noise from the test equipment 3 to the power supply 7 side of the test equipment 3 is used. In the case of a propagating wave traveling, it is determined as a partial discharge, and in the case of a propagating wave traveling from the power supply 7 side of the EUT 3 to the EUT 3, it is judged as noise and partial discharge is measured. . That is, the signal is discriminated and measured in the measurement device configuration, and the obtained signal is used as a partial discharge.

Japanese Patent Application Laid-Open No. 4-70573 discloses a method of selecting a frequency region with less noise and utilizing the characteristics of a partial discharge signal.
In the specification of No. 7, noise is discriminated by using a noise sensor or the like, and a signal obtained as an output of the measuring device at the time of measurement is a partial discharge.

As described above, the values measured by the conventional measuring device and measuring method are all partial discharges at the time when the measurement is completed, even if the measurement data is insufficient for noise removal. After that, the measurement data cannot be analyzed again to improve the accuracy of discriminating between noise and partial discharge.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and all measured pulse data is discriminated into a partial discharge and a noise from the characteristic amount and the signal amount of the noise and the partial discharge by a subsequent process. It is another object of the present invention to provide a partial discharge measuring device and method for detecting partial discharge.

Another object of the present invention is to provide a new knowledge on partial discharge that has become apparent after measurement.
It is an object of the present invention to provide a partial discharge measurement device and method capable of analyzing data again and improving the measurement accuracy of past partial discharge data.

[0018]

According to a first aspect of the present invention, there is provided a partial discharge measuring device for detecting a partial discharge and all the pulses including noise, and detecting the partial discharge from the pulse detected by the detecting unit. Signal processing means for extracting and digitizing a necessary signal amount, first storage means for temporarily storing digital signals processed by the signal processing means as measurement data, and accessing the first storage means for storing measurement data An electronic calculator for distinguishing the measurement data into a signal and a noise by a first arithmetic processing based on a characteristic amount of the partial discharge signal and the noise and displaying and storing the signal after the noise removal as a partial discharge; It is.

In a partial discharge measuring apparatus according to a second aspect of the present invention, the electronic storage means stores the measurement data from the first storage means and a signal after noise removal as a partial discharge. Means, and the first arithmetic processing based on the characteristic amount of the partial discharge signal and the noise.
The apparatus includes first arithmetic processing means for distinguishing the measurement data stored in the storage means into signals and noise, and display means for displaying the signal after noise removal as partial discharge.

According to a third aspect of the present invention, there is provided a partial discharge measuring device for detecting all pulses including partial discharge and noise, and extracting a signal amount necessary for partial discharge measurement from the pulses detected by the detecting unit. A signal processing unit for digitizing, a first storage unit for temporarily storing the digital signal processed by the signal processing unit as measurement data, and an access to the first storage unit for storing the measurement data, and a partial discharge signal. Electronic calculation means for discriminating the measurement data into a signal and a noise by a first arithmetic processing based on a signal amount of the noise, displaying the signal after noise removal as a partial discharge, and storing the signal;

According to a fourth aspect of the present invention, in the partial discharge measuring device, the electronic calculation means stores the measurement data from the first storage means and a signal after noise removal as a partial discharge. Means, and the first arithmetic processing based on the partial discharge signal and the signal amount of the noise.
The apparatus includes first arithmetic processing means for distinguishing the measurement data stored in the storage means into signals and noise, and display means for displaying the signal after noise removal as partial discharge.

According to a fifth aspect of the present invention, there is provided a partial discharge measuring device for detecting a partial discharge and all pulses including noise, and extracting a signal amount necessary for partial discharge measurement from the pulse detected by the detecting unit. A signal processing unit for digitizing, a first storage unit for temporarily storing a digital signal processed by the signal processing unit as measurement data, and after accessing the first storage unit and storing the measurement data, And electronic calculation means for discriminating between a signal and noise by a second operation processing reflecting the partial discharge signal amount based on new knowledge, displaying the signal after noise removal as a partial discharge, and storing the signal.

In a partial discharge measuring apparatus according to a sixth aspect of the present invention, the electronic storage means stores the measurement data from the first storage means and a signal after noise removal as a partial discharge. Means, a second arithmetic processing unit that identifies the measurement data stored in the second storage unit into a signal and a noise by a second arithmetic processing reflecting the partial discharge signal amount based on the new knowledge, and a second arithmetic processing unit after the noise removal. Display means for displaying a signal as a partial discharge.

According to a seventh aspect of the present invention, there is provided a partial discharge measuring device for detecting a partial discharge and all the pulses including noise, and extracting a signal amount necessary for the partial discharge measurement from the pulse detected by the detecting unit. A signal processing unit for digitizing, a first storage unit for temporarily storing a digital signal processed by the signal processing unit as measurement data, and after accessing the first storage unit and storing the measurement data, Electronic calculation means for discriminating between a signal and noise by a second calculation process reflecting the partial discharge characteristic amount based on new knowledge, displaying the signal after noise removal as a partial discharge, and storing the signal.

In a partial discharge measuring apparatus according to the present invention, the electronic calculation means stores the measurement data from the first storage means and a signal after noise removal as a partial discharge. Means, second arithmetic processing means for identifying measurement data stored in the second storage means into a signal and noise by a second arithmetic processing reflecting the partial discharge characteristic amount based on new knowledge, Display means for displaying a signal as a partial discharge.

According to a ninth aspect of the present invention, there is provided a partial discharge measuring device for detecting all pulses including partial discharge and noise, and extracting a signal amount required for partial discharge measurement from the pulses detected by the detecting unit. A signal processing unit for digitizing, a first storage unit for temporarily storing a digital signal processed by the signal processing unit as measurement data, and after accessing the first storage unit and storing the measurement data, Electronic calculation means for discriminating between a signal and noise by a signal amount comparison process between a plurality of sensors, displaying the signal after noise removal as partial discharge, and storing the partial discharge.

A partial discharge measuring apparatus according to a tenth aspect of the present invention is the partial discharge measuring device, wherein the detecting means detects all the pulses including the partial discharge and noise, and a signal amount required for the partial discharge measurement from the pulse detected by the detecting means. Signal processing means for extracting and digitizing the data, and the first storage means for temporarily storing the digital signal processed by the signal processing means as measurement data, comprising a plurality of channels and measuring signals from a plurality of partial discharge sensors. Is what you do.

According to an eleventh aspect of the present invention, in the partial discharge measuring device, the partial discharge measuring device is used for a partial discharge measuring device of a high-voltage rotating electric machine.

According to a twelfth aspect of the present invention, there is provided a partial discharge measuring method for detecting all pulses including partial discharge and noise.
A second step of extracting and digitizing a signal amount necessary for partial discharge measurement from the detected pulse, a third step of temporarily storing the digital signal as measurement data, and a characteristic amount of the partial discharge signal and noise. And a fifth step of displaying the signal after noise removal as a partial discharge and storing the same as a partial discharge by a first operation process based on the above.

A partial discharge measuring method according to a thirteenth aspect of the present invention is the first method for detecting all pulses including partial discharge and noise.
A second step of extracting and digitizing a signal amount necessary for partial discharge measurement from the detected pulse, a third step of temporarily storing the digital signal as measurement data, and a signal amount of a partial discharge signal and a noise. And a fifth step of displaying the signal after noise removal as a partial discharge and storing the same as a partial discharge by a first operation process based on the above.

According to a fourteenth aspect of the present invention, there is provided a partial discharge measuring method for detecting all pulses including partial discharge and noise.
A second step of extracting a signal amount necessary for partial discharge measurement from the detected pulse and digitizing the same, a third step of temporarily storing the digital signal as measurement data, and acquiring the measurement data with new knowledge. And a fifth step of displaying the signal after noise removal as a partial discharge and storing the same as a partial discharge by a second operation process reflecting the partial discharge signal amount of the signal.

According to a fifteenth aspect of the present invention, there is provided a partial discharge measuring method for detecting all pulses including partial discharge and noise.
A second step of extracting a signal amount necessary for partial discharge measurement from the detected pulse and digitizing the same, a third step of temporarily storing the digital signal as measurement data, and acquiring the measurement data with new knowledge. And a fifth step of displaying the signal after noise removal as a partial discharge and storing the same as a partial discharge by a second operation process reflecting the partial discharge characteristic amount of the signal.

[0033] A partial discharge measuring method according to a sixteenth aspect of the present invention is the first method for detecting all pulses including partial discharge and noise.
A second step of extracting and digitizing a signal amount necessary for partial discharge measurement from the detected pulse, a third step of temporarily storing the digital signal as measurement data, and transmitting the measurement data between a plurality of sensors. And a fifth step of displaying the signal after noise removal as partial discharge and storing the same as a signal and a noise by the signal amount comparison processing.

In the method of measuring a partial discharge according to a seventeenth aspect of the present invention, the first step of detecting all the pulses including the partial discharge and noise, and the step of determining a signal amount required for the partial discharge measurement from the detected pulse The second step of taking out and digitizing and the third step of temporarily storing the digital signal as measurement data are configured by a plurality of channels and measure signals from a plurality of partial discharge sensors.

[0035] In a partial discharge measuring method according to an eighteenth aspect of the present invention, the partial discharge measuring method is used for a partial discharge measuring method of a high-voltage rotating electric machine.

[0036]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

Embodiment 1 FIG. 1 is a configuration diagram showing a schematic configuration of a partial discharge measuring device according to Embodiment 1 of the present invention. In FIG. 1, a partial discharge measuring device 20 includes a partial discharge sensor 21, a detecting unit 22, and a signal processing unit 26.
, A first storage means 30, an electronic computer 36 as an electronic calculation means, a data bus 37 connecting the first storage means 30 and the electronic computer 36, a transformer 39, and a phase detector 40. . The computer 36 stores the first file 3
A second storage unit 33 including a first file and a second file 32;
It comprises a first arithmetic processing means 34 and a display means 35.

The partial discharge sensor 21 is installed adjacent to the stator winding of the rotating electric machine or connected to the high voltage lead of the stator winding, and is the same as the above-described prior art partial discharge sensor. is there. The transformer 39 is provided for measuring the voltage phase applied to the stator winding.

Next, the operation of the partial discharge measuring device 20 according to the first embodiment will be described with reference to FIGS. FIG. 2 is a flowchart showing the operation of the first embodiment.

In electrical equipment such as a high-voltage rotating machine, when insulation deterioration progresses, partial discharge occurs due to application of high voltage during operation. A high-frequency signal accompanying the occurrence of the partial discharge is detected by a partial discharge sensor 21 installed inside or outside the electric device. The signal to be detected is a high-speed pulse signal including a frequency component up to 1 GHz. The partial discharge sensor 21 includes:
Noise is detected simultaneously with the partial discharge. During operation of the rotating electric machine, noise that is larger than the partial discharge signal often occurs inside the device, and these noises are detected by the partial discharge sensor 21 as in the case of partial discharge. Further, noise generated outside the device propagates through the high-voltage conductor and is detected by the partial discharge sensor 21. In many cases, radioactive noise in the air is induced and detected by the partial discharge sensor 21 or the detection circuit system.

A pulse in which these partial discharges and noise are mixed is input to the detecting means 22. In the detecting means 22,
The input pulse is adjusted so as to be within a detection voltage range that can be processed by the signal processing means 26 at the subsequent stage, and the pulse detected through the narrow-band filters 25a and 25b in which the characteristics of the signal and the noise become remarkable is converted into a signal. It is transmitted to the processing means 26.

The signal processing means 26 converts a pulse signal in which a partial discharge of an analog signal and noise are mixed into a digital signal. The signal processing means 26 performs an analog / digital conversion of a signal amount required for the first arithmetic processing by the first arithmetic processing means 34 at the subsequent stage for each passing pulse. Here, the partial discharge and the signal amount of noise mean values such as a pulse waveform, a peak value, a rise time (Rise time), a fall time, a pulse width, an envelope of a waveform, and a generation phase. . The rise time and the fall time are achieved, for example, by measuring the arrival time difference between the signal value at the 20% level and the signal value at the 90% level with respect to the peak value. The waveform and the pulse width are achieved by measuring a plurality of equal levels with respect to the peak value. in this way,
Only the characteristic values necessary for discrimination between partial discharge and noise in the pulse waveform are converted to analog. This signal processing means 26
Since only the amount of signal necessary for discrimination between partial discharge and noise is digitized, it can be manufactured small and inexpensively.
As a device for performing analog / digital conversion of a pulse waveform such as partial discharge or noise, there is a digital oscilloscope or the like. Since the digital oscilloscope is designed to measure a waveform or the like in detail, a large amount of memory is required to record one pulse. Hundreds to tens of thousands of partial discharges and noise pulses are generated every second, and measurement of partial discharge pulses of several hundred to several thousand pulses / second is required to grasp the partial discharge characteristics. For this reason, measurement of partial discharge during operation using a digital oscilloscope or the like requires an enormous amount of memory and is an expensive device, so there is no merit. The digitally converted pulse is transmitted to the first storage means 30.

In the first storage means 30, in response to a measurement start command from the electronic computer 36 (step ST1), the pulse signal is measured from the determined phase of the voltage signal obtained by the transformer 39, detected by the phase detection means 40. Is started (step ST2), the signal amount of all the pulses generated in a fixed time is converted from analog to digital together with the voltage phase information (step ST3), and stored as measurement data (step ST4). The measurement time for acquiring data is determined by the relationship between the measured signal amount and the storage capacity of the first storage means 30,
In the case of a steady partial discharge generated due to insulation deterioration, one measurement only needs to be several seconds, and when the accuracy is further improved, this measurement may be repeated. Electronic computer 36
Are issued at intervals of several minutes if shorter and at intervals of several hours if longer, depending on the operation history of the rotating electrical machine and the degree of need of the user.

After storage in the first storage means 30, the computer 3
6 to access the first storage means 30 to store the measurement data in the first file 31 of the second storage means 33 (step ST5). Further, the measurement data stored in the first file 31 by the first arithmetic processing means 34 is identified as partial discharge and noise based on a previously programmed signal amount and characteristic amount of partial discharge and noise (step ST6). Noise is removed based on the result (step ST
7), storing only the partial discharge as the partial discharge data in the second file 32 of the second storage means 33 (step ST)
8) Both are displayed on the display means 35 (step ST)
9). Here, the characteristic amount of partial discharge and noise in the present invention refers to a difference in signal propagation characteristics between partial discharge and noise, a frequency characteristic based on signal propagation, an amplitude value, an arrival time, and the like. , Or a value based on the fact that the characteristics among a plurality of sensors differ between partial discharge and noise.

In the present invention, the measurement data stored in the first file 31 is data containing noise, and the first arithmetic processing means 34 performs a process of discriminating between partial discharge and noise. The first arithmetic processing means 34 compares not only a single characteristic amount but also a plurality of characteristic amounts that are different in partial discharge and noise.

As described above, during operation of the rotating electric machine, a number of partial discharges and noise larger than that are generated, and the noise separation determines the measurement accuracy. Paying attention, signals and noise can be distinguished for each generated pulse by arithmetic processing by software. Further, the first arithmetic processing means 34 for noise separation can combine not only one type of arithmetic but also a plurality of types of arithmetic processing and processing methods based on characteristic amounts of partial discharge and noise. Therefore, the noise removal accuracy can be improved at a lower cost than the noise separation realized by a hardware circuit configuration.

Although the rotating electric machine has been described in the first embodiment, the present invention can be applied to other high-voltage devices by performing an arithmetic process based on the characteristics of partial discharge and noise of the target high-voltage device. be able to. Further, in the first embodiment, the first storage unit 30 is described as being configured separately from the computer 36, but may be provided in the computer 36.

The partial discharge measuring method according to the first embodiment is performed by the partial discharge measuring device 20, and includes a first step of detecting all pulses including partial discharge and noise; A second step of extracting and digitizing a signal amount necessary for partial discharge measurement from the generated pulse, a third step of temporarily storing the digital signal as measurement data, and a second step based on the characteristic amount or signal amount of the partial discharge signal and noise. The method includes a fourth step of distinguishing the measurement data into a signal and noise by one arithmetic processing, and a fifth step of displaying and storing the signal after noise removal as partial discharge.

Embodiment 2 FIG. 3 is a configuration diagram showing a schematic configuration of a partial discharge measurement device according to a second embodiment of the present invention. 3, a partial discharge measuring device 20A according to the second embodiment includes a partial discharge sensor 21, a detecting unit 22, a signal processing unit 26, a first storage unit 30, an electronic computer 36A, a transformer 39, , A phase detecting means 40, and the computer 36A comprises a first file means 31, a second file means 32, and a third file means 45.
A second storage means 33A comprising:
The electronic computer 36A and the first storage means 30 are composed of a display means 35 and a second arithmetic processing means 43.
7. Also, the second arithmetic processing means 43
, A new data processing algorithm 42 created based on the new knowledge 41 is input.

Next, the operation of the apparatus according to the second embodiment will be described with reference to the flowcharts of FIGS. The partial discharge or noise induced by the partial discharge sensor 21 is detected by the detection unit 22, the required signal amount is converted into a digital signal by the signal processing unit 26, stored in the first storage unit 30, and further processed by the first arithmetic processing unit 34. A process of discriminating the partial discharge signal from the noise is performed, the data after the noise is separated is stored in the second file unit 32, and the result is displayed on the display unit 35. The operation so far is the same as in the first embodiment.

The subsequent processing is unique to the second embodiment. The measurement data including the partial discharge and the noise for measuring the partial discharge are recorded in the first file unit 31 of the second storage unit 33. Here, after the first measurement is completed, the signal amount and characteristic amount (characteristics of the partial discharge and the noise) obtained by new knowledge are obtained (step ST
Based on 11), a new data processing algorithm 42 is constructed (step ST12). The measurement data stored in the first file 31 of the second storage means 33 is read by the second arithmetic processing means 43 using the arithmetic processing constructed by the new data processing algorithm 42 (step ST14), and the second arithmetic processing is performed. Then, the partial discharge signal and noise are newly discriminated (step ST15), the noise is removed based on the discrimination result (step ST16), and the result is stored in the third file 45 of the second storage unit 33 (step ST15). ST1
7) is displayed together with the display means 35 (step ST1).
8). Further, it accesses the second file means 32 and compares it with the data from which noise has been separated by the first arithmetic processing means 34 (step ST19).

As described above, partial discharge and noise can be discriminated from the measurement data including partial discharge and noise measured during the operation of the rotating electric machine by the second arithmetic processing based on new knowledge. The partial discharge data can be analyzed again with improved measurement accuracy. The conventional partial discharge measurement data itself is final data, and it was not possible to analyze past data with higher accuracy again. According to the present invention, since past data can be analyzed again, past measurement data can be analyzed as if re-measured by reflecting new research results, and measurement accuracy can be improved. In addition, the past measurement data can be compared with new analysis results to analyze the state of noise and the progress of insulation deterioration.

In the first and second embodiments, a description has been given of a rotating electric machine. Can also be applied.

The partial discharge measuring method according to the second embodiment is performed by the partial discharge measuring device 20A, and includes a first step of detecting all pulses including partial discharge and noise, A second step of extracting and digitizing a signal amount required for partial discharge measurement from the pulse obtained, a third step of temporarily storing the digital signal as measurement data, and a step of partially measuring the partial discharge signal amount or A fourth step of discriminating between a signal and a noise by the second operation processing reflecting the characteristic amount, a fifth step of displaying and storing the signal after noise removal as a partial discharge,
And a sixth step of comparing with past data.

Embodiment 3 FIG. 5 shows the configuration of the partial discharge measuring device according to the third embodiment of the present invention. FIG.
In the partial discharge measuring device 20B of the third embodiment,
Is a plurality (three in the illustrated example) of partial discharge measurement channels 51, a plurality of (four in the illustrated example) noise measurement channels 52, and a computer 36A similar to the second embodiment.
, A transformer 39, and a phase detecting means 40.

Each partial discharge measurement channel 51 includes a partial discharge sensor 21a, a first detecting means 22a, a first signal processing means 26a, and a storage means 30a. Each first detecting means 22a includes an attenuator 23a. An amplifier 24a connected in series at a stage subsequent to the attenuator 23a;
a plurality of narrow bandpass filters 25 branched into two circuits at the subsequent stage
a, 25b, and each first signal processing means 26
a denotes amplifiers 24b and 24c and a peak hold circuit 2
7a, 27b and analog / digital converters 28a, 2
8b, and each storage means 30a has a RAM
29a and 29b.

The noise measurement channel 52 includes a noise sensor 46, a second detection unit 22b, a second signal processing unit 26b, and a storage unit 30b including a RAM 29c. An attenuator 23c, an amplifier 24c, and a narrow-band filter 2 connected in series
5c, and each second signal processing means 26b
It comprises an amplifier 24d, a peak hold circuit 27c, and an analog / digital converter 28c. Here, each noise sensor 46 is installed at a location where noise is generated or a location where noise enters during operation of the rotating electric machine. That is, the noise sensor 46 includes a noise sensor for detecting a minute arc of the rotor shaft ground brush, a noise sensor for detecting a minute arc of the exciter slip ring, a sensor for detecting intrusion noise from the phase separation bus, and a minute arc installed in the rotating electric machine. A detection sensor, a radiation noise detection sensor installed outside the apparatus, and the like, and two or more plural sensors are installed.

In the third embodiment, a plurality of first detecting means 22a and a plurality of second detecting means 22b constitute a detecting means 22, and a plurality of first signal processing means 26a
And a plurality of second signal processing means 26b constitute a signal processing means 26, and furthermore, a plurality of storage means 30a, 30b
Constitutes the first storage means 30.

Further, as in the case of the second embodiment, the computer 36A stores the second storage means 33A comprising the first file 31, the second file 32 and the third file 45.
, A first arithmetic processing means 34, a display means 35, and a second arithmetic processing means 43. The computer 36A is connected to the first storage means 30 by a data bus 37.
The second arithmetic processing means 43 is connected to the second
It is connected to the storage means 33A. A new data processing algorithm 42 is created based on the new knowledge 41, and the new data processing algorithm 42 is
The second arithmetic processing means 43 performs a new arithmetic processing based on the new data processing algorithm 42.

Next, the operation of the partial discharge measuring device 20B according to the third embodiment will be described. Embodiment 1
As described above, when a pulse in which partial discharge and noise are mixed is input to the detection means 22, the detection means 22 sets the attenuator 23a and the amplifier so that the voltage range can be processed by the signal processing means 26 at the subsequent stage. The detected pulses are transmitted to the signal processing means 26 through the narrow-band filters 25a and 25b in which the characteristics of the signals 24a and 24b and the noise become remarkable. A plurality of narrow-band filters 25a and 25b are provided for branching into two or more bands and detecting them in order to distinguish between a partial discharge signal and noise. FIG. 5 shows an example in two bands. The signal amplification is performed by each of the narrow-band filters 25a and 25b.
This is performed in the first and second stages. This is because, in normal stator winding insulation, the partial discharge during operation is buried about an order of magnitude smaller than the noise, so when using the frequency characteristics of each pulse to distinguish between partial discharge and noise, a narrow band Filters 25a, 2
This is to prevent the characteristics of the pass band of each pulse from changing even through 5b. In the amplifier 24a, all the pulses guided to the partial discharge sensor are passed through the narrow bandpass filters 25a and 25b at such an intensity that they do not saturate.
b. Amplify and measure at 24c.

In the signal processing means 26, the amplifiers 24b, 2
The pulse signal mixed with partial discharge and noise of the analog signal amplified by 4c is converted into a digital signal. The signal processing means 26 performs an analog / digital conversion of a signal amount required for the first arithmetic processing means 34 at the subsequent stage for each passing pulse. Also, the noise pulse of the noise measurement channel 52 is similarly converted into a digital signal. The digitally converted pulse is transmitted to the first storage means 30 and stored therein. The above operation is simultaneously executed on all the channels. In the first storage means 30, the same pulse is simultaneously measured in the plurality of partial discharge channels 51 and the plurality of noise measurement channels 52 by the same operation as described in the first embodiment, and the measurement data is stored.

After storage in the first storage means 30, the computer 3
6A accesses the first storage unit 30 and stores the measurement data in the first file 31 of the second storage unit 33A. Further, the measurement data stored in the first file 31 is identified as a partial discharge and a noise by the first arithmetic processing means 34 by a first arithmetic processing based on a signal amount and a characteristic amount of the partial discharge and the noise programmed in advance, Only the partial discharge is stored in the second file 32 of the second storage unit 33A as partial discharge data, and is displayed on the display unit 35. Here, the characteristic amount of partial discharge and noise is a value based on the difference in signal propagation characteristics between partial discharge and noise, frequency characteristics based on signal propagation, amplitude value, arrival time, etc., between partial discharge and noise. It is.

In the present invention, the measurement data stored in the first file 31 is data containing noise, and the first arithmetic processing means 34 performs a process of discriminating between partial discharge and noise. The first arithmetic processing means 34 compares not only a single characteristic amount but also a plurality of characteristic amounts that are different between partial discharge and noise.

In the present invention, the state of each noise sensor installation location is analyzed from the signal strength of each noise measurement channel 52 in consideration of the load and operating temperature of the rotating electric machine after measurement, and the rotor shaft ground brush is measured. , An abnormality in the discharge state of the slip ring, the phase separation bus, the inside of the rotating electric machine, and the like.

The partial discharge measuring method according to the second embodiment is performed by the partial discharge measuring device 20B, and includes a first step of detecting all pulses including partial discharge and noise, A second step of extracting and digitizing a signal amount necessary for partial discharge measurement from the applied pulse, a third step of temporarily storing the digital signal as measurement data, and comparing the measurement data with a signal amount between a plurality of sensors. It comprises a fourth step of distinguishing between signals and noise, and a fifth step of displaying and storing the signal after noise removal as partial discharge. Further, the first step of detecting all pulses including the partial discharge and noise, the second step of extracting a signal amount necessary for partial discharge measurement from the detected pulse and digitizing the first signal, The third step of temporarily storing the measurement data is as follows:
It is composed of a plurality of channels, and signals from a plurality of partial discharge sensors are measured.

Embodiment 4 Next, a partial discharge measuring method and device according to a fourth embodiment of the present invention will be described. That is, partial discharge measurement is performed by applying the invention described in the first to third embodiments to a high-voltage rotating electric machine. During operation of the rotating electric machine, the rotor shaft ground brush of the generator,
Noise such as an exciter slip ring, core back discharge, and intrusion noise from the system side generates or intrudes noise one digit larger than the partial discharge signal, and is detected by the partial discharge sensor. These are major obstacles to partial discharge measurement,
By performing measurement using the partial discharge measurement method and apparatus according to the above-described first to third embodiments, partial discharge and noise can be clearly distinguished, so that partial discharge measurement can be achieved during operation.

[0067]

As described above, according to the present invention, all pulses including partial discharge and noise are detected, a signal amount necessary for measuring partial discharge is extracted from the detected pulses, and digitization is performed. The digital signal obtained is temporarily stored in the first storage means as measurement data, the measurement data is stored in the first file of the second storage means by accessing the first storage means, and based on the characteristic amount of the partial discharge signal and noise. First
By discriminating the measurement data of the first file into a signal and noise by the arithmetic processing, there is an effect that each detected pulse can be separated into a partial discharge signal and noise. Further, by using the partial discharge measuring device and method, there is an effect that a partial discharge generated during the operation of the rotating electric machine can be accurately detected in an operating state. Also,
The first arithmetic processing for noise separation is not limited to one type of arithmetic, but can be a combination of arithmetic processing and processing methods based on a plurality of types of partial discharges and the characteristic amount of noise.
There is an effect that the noise removal accuracy can be improved at a lower cost than the noise separation realized by the circuit configuration.

Further, according to the present invention, all pulses including partial discharge and noise are detected, a signal amount necessary for partial discharge measurement is extracted from the detected pulse, and a digitizing process is performed. The measurement data is temporarily stored in the first storage means, the first storage means is accessed to store the measurement data in the first file of the second storage means, and the first calculation based on the signal amount of the partial discharge signal and the noise is performed. By processing, the measurement data of the first file is identified as a signal and a noise, whereby there is an effect that a partial discharge generated during the operation of the rotating electrical machine can be accurately detected in an operation state.

Further, according to the present invention, all pulses including partial discharge and noise are detected, a signal amount necessary for partial discharge measurement is extracted from the detected pulses, and a digitizing process is performed. Since the data is stored as the measurement data, there is an effect that the signal and the noise can be distinguished by the arithmetic processing reflecting the partial discharge signal amount based on new knowledge after the measurement. Therefore, there is an effect that the past measurement data can be re-analyzed to improve the measurement accuracy. In particular, for important equipment such as large-capacity generators that cannot be easily stopped once started and cannot be easily re-measured, the past data is analyzed with the latest knowledge to understand the operating state. What you can do has a huge effect.

Further, according to the present invention, all pulses including partial discharge and noise are detected, a signal amount necessary for partial discharge measurement is extracted from the detected pulses, and a digitizing process is performed. Is stored as measurement data, so that it is possible to distinguish between signals and noise by arithmetic processing reflecting the partial discharge characteristic amount based on new knowledge after measurement, and to display the signal after noise removal as partial discharge. is there. In addition, since the oldest measurement data measured by the measurement device or method of the present invention can be processed many times by the latest signal separation processing,
There is an effect that analysis can be performed with higher accuracy as if old measurement data was re-measured.

Further, according to the present invention, the same pulse simultaneously detected by a plurality of sensors is subjected to a signal amount comparison process for each pulse to discriminate a signal from a noise and to remove the noise.

Further, according to the present invention, pulses from a plurality of partial discharge sensors and a plurality of noise sensors constituted by a plurality of channels can be simultaneously measured.
There is an effect that a signal and noise can be distinguished from a pulse comparison between a plurality of channels and noise can be removed.

Further, according to the present invention, there is an effect that a very useful partial discharge measuring device and a partial discharge measuring method can be obtained when applied to a high-voltage rotating electric machine.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a partial discharge measuring device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing an operation of the partial discharge measuring device according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a partial discharge measuring device according to a second embodiment of the present invention.

FIG. 4 is a flowchart showing an operation of the partial discharge measuring device according to the second embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a partial discharge measuring device according to a third embodiment of the present invention.

FIG. 6 is a block diagram showing a configuration of a conventional partial discharge measuring device.

[Explanation of symbols]

3 Test machine (rotary electric machine), 4 lead wire, 5 voltage wave detection circuit, 6 current amount detection circuit, 7 power supply, 8 gate circuit, 9 discharge amount measurement circuit, 10 polarity discrimination circuit, 11
Polarity discriminating circuit, 12 seeding wave traveling direction discriminating circuit, 20,
20A, 20B partial discharge measuring device, 21 partial discharge sensor, 22 detecting means, 23a, 23c attenuator, 24a,
24b, 24c amplifier, 25a, 25b, 25c narrow band filter, 26 signal processing means, 27a, 27b, 2
7c peak hold, 28a, 28b, 28c analog / digital converter, 29a, 29b, 29c storage device, 30 first storage means, 31a, 31b, 31c
First file, 32 second file, 33 second storage means, 34 first calculation processing, 35 display means, 36, 36
A computer, 37 data bus a, 39 transformer,
40 phase detecting means, 41 new knowledge, 42 new data processing algorithm, 43 second arithmetic processing, 44 data bus b, 45 third file, 46 noise sensor a, 47 noise sensor b, 48 noise sensor c, 49
Noise sensor d, 51 Partial discharge measurement channel, 5
2 Noise channel.

Continued on the front page (72) Inventor Shinji Sato 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation (72) Inventor Shigeo Kitamura 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Co., Ltd. Inside the company (72) Inventor Okada ▲ Iwao ▼ 3-2-2, Nakanoshima, Kita-ku, Osaka City, Osaka Prefecture Inside Kansai Electric Power Co., Inc. (72) Satoru Kuroki 3-2-2, Nakanoshima, Kita-ku, Osaka City, Osaka Kansai Inside Electric Power Company (72) Inventor Katsunori Otowa 3-2-2 Nakanoshima, Kita-ku, Osaka-shi, Osaka Kansai Electric Power Company (72) Inventor Teruya Osawa 3-2-2, Nakanoshima, Kita-ku, Osaka, Kansai Inside Electric Power Company

Claims (18)

[Claims] A detecting means for detecting all pulses including partial discharge and noise; a signal processing means for extracting a signal amount necessary for partial discharge measurement from the pulses detected by the detecting means and digitizing the signal; First storage means for temporarily storing the digital signal processed by the means as measurement data, and storing the measurement data by accessing the first storage means, and performing first arithmetic processing based on the characteristic amount of the partial discharge signal and noise. An electronic calculation means for distinguishing the measurement data into a signal and noise and displaying and storing the signal after noise removal as a partial discharge. 2. The partial discharge measuring device according to claim 1, wherein the electronic calculation unit stores the measurement data from the first storage unit and stores a signal after noise removal as a partial discharge.
Storage means, first operation processing means for discriminating the measurement data stored in the second storage means into signals and noise by a first operation processing based on the characteristic amount of the partial discharge signal and noise, Display means for displaying a signal as a partial discharge; and a partial discharge measurement device. 3. A detecting means for detecting all pulses including partial discharge and noise, a signal processing means for extracting a signal amount necessary for partial discharge measurement from the pulses detected by the detecting means and digitizing the signal, and the signal processing. First storage means for temporarily storing the digital signal processed by the means as measurement data, and storing the measurement data by accessing the first storage means, and performing first arithmetic processing based on the partial discharge signal and the signal amount of noise. An electronic calculation means for distinguishing the measurement data into a signal and noise and displaying and storing the signal after noise removal as a partial discharge. 4. The partial discharge measuring device according to claim 3, wherein the electronic calculation unit stores the measurement data from the first storage unit and stores a signal after noise removal as a partial discharge.
Storage means; first operation processing means for discriminating measurement data stored in the second storage means into signals and noise by first operation processing based on the signal amounts of the partial discharge signal and noise; Display means for displaying a signal as a partial discharge; and a partial discharge measurement device. 5. A detecting means for detecting all pulses including partial discharge and noise, a signal processing means for extracting a signal amount necessary for partial discharge measurement from the pulses detected by the detecting means and digitizing the signal, and the signal processing. First storage means for temporarily storing the digital signal processed by the means as measurement data; and after accessing the first storage means and storing the measurement data, the measurement data reflects the partial discharge signal amount based on new knowledge. An electronic calculation means for discriminating between a signal and noise by the second arithmetic processing and displaying and storing the signal after noise removal as a partial discharge. 6. The partial discharge measuring device according to claim 5, wherein the electronic calculation unit stores the measurement data from the first storage unit and stores a signal after noise removal as a partial discharge.
Storage means; second operation processing means for discriminating the measurement data stored in the second storage means into signals and noise by a second operation processing reflecting the partial discharge signal amount based on the new knowledge; And a display means for displaying the signal of the partial discharge as a partial discharge. 7. A detecting means for detecting all pulses including partial discharge and noise, a signal processing means for extracting a signal amount necessary for partial discharge measurement from the pulses detected by the detecting means and digitizing the signal, and the signal processing. First storage means for temporarily storing the digital signal processed by the means as measurement data; and after accessing the first storage means and storing the measurement data, the measurement data reflects the partial discharge characteristic amount based on new knowledge. An electronic calculation means for discriminating between a signal and noise by the second arithmetic processing and displaying and storing the signal after noise removal as a partial discharge. 8. The partial discharge measuring device according to claim 7, wherein the electronic calculation means stores the measurement data from the first storage means and stores a signal after noise removal as a partial discharge.
Storage means; second operation processing means for discriminating the measurement data stored in the second storage means into a signal and noise by a second operation processing reflecting the partial discharge characteristic amount based on the new knowledge; And a display means for displaying the signal of the partial discharge as a partial discharge. 9. A detecting means for detecting all pulses including partial discharge and noise, a signal processing means for extracting a signal amount necessary for measuring partial discharge from the pulses detected by the detecting means and digitizing the signal, and the signal processing. First storage means for temporarily storing the digital signal processed by the means as measurement data; and after accessing the first storage means and storing the measurement data, the measurement data is subjected to signal amount comparison processing between a plurality of sensors. And an electronic calculation means for identifying the noise as noise and displaying and storing the signal after noise removal as a partial discharge, and a partial discharge measuring device. 10. The partial discharge measuring device according to claim 1, wherein the detecting means detects all pulses including the partial discharge and noise, and the partial discharge is detected from the pulses detected by the detecting means. A signal processing unit for extracting and digitizing a signal amount required for measurement, and the first storage unit for temporarily storing a digital signal processed by the signal processing unit as measurement data,
A partial discharge measuring device comprising a plurality of channels and measuring signals from a plurality of partial discharge sensors. 11. A partial discharge measuring device for a high voltage rotating electric machine, wherein the partial discharge measuring device according to claim 1 is used for a partial discharge measuring device for a high voltage rotating electric machine. 12. A first step of detecting all pulses including partial discharge and noise, a second step of extracting a signal amount necessary for partial discharge measurement from the detected pulse and digitizing the first signal, and Third to temporarily save as measurement data
And a fourth operation for discriminating the measurement data into a signal and a noise by a first operation based on a characteristic amount of the partial discharge signal and the noise.
And a fifth step of displaying and storing the signal after noise removal as a partial discharge and storing the signal as a partial discharge. 13. A first step of detecting all pulses including partial discharge and noise, a second step of extracting a signal amount required for partial discharge measurement from the detected pulses and digitizing the first signal, and Third to temporarily save as measurement data
And a fourth operation for discriminating the measurement data into a signal and a noise by a first arithmetic processing based on the signal amounts of the partial discharge signal and the noise.
And a fifth step of displaying and storing the signal after noise removal as a partial discharge and storing the signal as a partial discharge. 14. A first step of detecting all pulses including partial discharge and noise, a second step of extracting and digitizing a signal amount necessary for partial discharge measurement from the detected pulses, and Third to temporarily save as measurement data
And a fourth step of discriminating the measurement data into a signal and a noise by a second calculation process reflecting the partial discharge signal amount based on new knowledge. The signal after the noise removal is displayed and stored as a partial discharge. A method for measuring partial discharge, comprising: a fifth step. 15. A first step of detecting all pulses including partial discharge and noise, a second step of extracting a signal amount necessary for partial discharge measurement from the detected pulses and digitizing the first signal, and Third to temporarily save as measurement data
And a fourth step of discriminating the measurement data into a signal and a noise by a second calculation process reflecting the partial discharge characteristic amount based on the new knowledge, and displaying and storing the signal after the noise removal as a partial discharge. A method for measuring partial discharge, comprising: a fifth step. 16. A first step of detecting all pulses including partial discharge and noise, a second step of extracting a signal amount necessary for partial discharge measurement from the detected pulses and digitizing the signal, and Third to temporarily save as measurement data
And a fourth step of distinguishing the measurement data into a signal and a noise by a signal amount comparison process between a plurality of sensors, and a fifth step of displaying and storing the signal after noise removal as a partial discharge. A partial discharge measuring method characterized by the above-mentioned. 17. The partial discharge measurement method according to claim 12, wherein the first step of detecting all the pulses including the partial discharge and the noise, and measuring the partial discharge from the detected pulse. The second step of extracting and digitizing a signal amount necessary for the first step and the third step of temporarily storing the digital signal as measurement data include a plurality of channels, and measure signals from a plurality of partial discharge sensors. A partial discharge measurement method, characterized in that: 18. A partial discharge measuring method for a high-voltage rotating electric machine, wherein the partial discharge measuring method according to claim 12 is used for a partial discharge measuring method for a high-voltage rotating electric machine.