JP2022023274A - Electric discharge assessment device and method therefor - Google Patents

Abstract

To more easily assess whether there is occurrence of an electric charge to a winding.SOLUTION: The present invention includes: measuring a first electric discharge occurrence estimated time slot Rt1 on the basis of first time-series voltage data obtained by applying an impulse voltage Vi to both ends of a winding 20 and Fourier-transforming the first time-series voltage data so as to find a frequency spectrum (steps S100-S106); extracting only an electric discharge-specific frequency component from the frequency spectrum (step S108); and reverse-Fourier-transforming the extracted frequency spectrum so as to find second time-series voltage data (step S110). The present invention further includes: finding a maximum voltage value Vmax1 and first time T1 from the first electric discharge occurrence estimated time slot Rt1 of the second time-series voltage data (step S112); estimating that there is occurrence of electric discharge when the first time T1 falls within a threshold range (step S114); and comparing the maximum voltage value Vmax1 with a threshold Vth so as to assess the occurrence of the electric discharge (steps S116-S120).SELECTED DRAWING: Figure 2

Description

The present invention relates to a discharge determination device for determining whether or not a discharge is generated in a winding of an electric device, a discharge determination method, and a program.

Japanese Patent Application Laid-Open No. 7-260868 (Patent Document 1) describes a discharge determination device for determining whether or not a partial discharge has occurred in an electric device. The discharge determination device first divides waveforms such as currents and electromagnetic waves generated from electrical equipment into each cycle and creates a plurality of sampling data. Next, the averaged data is created by synchronizing the waveforms of these plurality of sampling data and then averaging them. Subsequently, the noise signal is removed by taking the difference between the averaged data and any one sampling data among the plurality of sampling data. Only the partial discharge signal is taken out in the final data from which the noise signal is removed in this way. In this way, the presence or absence of the occurrence of partial discharge is determined.

Japanese Unexamined Patent Publication No. 7-260868

However, the discharge determination device described in the above-mentioned publication requires a large number of data for determining the presence or absence of discharge, and the calculation is complicated, so that there is still room for improvement.

The present invention has been made in view of the above, and an object of the present invention is to provide a technique capable of more easily determining whether or not a discharge has occurred.

According to a preferred embodiment of the discharge determination device according to the present invention, a discharge determination device for determining whether or not a discharge is generated in the winding of an electric device is configured. The discharge determination device includes an applied voltage generation circuit, a detector, a time zone measurement unit, a Fourier transform unit, a frequency component extraction unit, an inverse Fourier transform unit, a feature quantity extraction unit, and a threshold range setting unit. , An estimation unit and a determination unit. The applied voltage generation circuit is connected to both ends of the winding so that an impulse voltage or a pulse voltage can be applied to both ends of the winding. Based on the first time-series voltage data or the first time-series current data detected by the detector, the time zone measuring unit reduces the voltage or current from the time when the impulse voltage or pulse voltage is applied to zero after the voltage or current increases. Measure the first time zone until it becomes. The detector is a determination circuit for detecting the first time-series voltage data observed at both ends of the winding or the first time-series current data flowing in the determination circuit including the winding and the applied voltage generation circuit. Connected to. The Fourier transform unit obtains a frequency spectrum by Fourier transforming the first time-series voltage data or the first time-series current data detected by the detector. The frequency component extraction unit extracts only the frequency component peculiar to the discharge from the frequency spectrum. The inverse Fourier transform unit obtains the second time-series voltage data or the second time-series current data by inverse-Fourier transforming the frequency spectrum in the extracted frequency component peculiar to the discharge. The feature amount extraction unit obtains the first maximum voltage value or the first maximum current value, and the first time. The first maximum voltage value or the first maximum current value is the maximum value of the voltage or current observed in the first time zone of the second time series voltage data or the second time series current data. The first time is the time from when the impulse voltage or the pulse voltage is applied until the first maximum voltage value or the first maximum current value is observed. The threshold range setting unit sets the first threshold range by applying the applied impulse voltage or pulse voltage to the first discharge estimation map in which the relationship between the impulse voltage or the pulse voltage and the discharge generation time is predetermined. The estimation unit estimates that a discharge has occurred in the winding if the first time is within the first threshold range, and if the first time is outside the first threshold range, no discharge has occurred in the winding. Is determined. Then, when it is estimated by the estimation unit that a discharge is generated in the winding, the determination unit compares the first maximum voltage value or the first maximum current value with the first threshold value, and the first maximum voltage. When the value or the first maximum current value is larger than the first threshold value, it is determined that the winding is discharged, and when the first maximum voltage value or the first maximum current value is equal to or less than the first threshold value, the winding is connected. It is determined that no discharge has occurred. Here, the "discharge-specific frequency component" in the present invention is defined as a specific frequency component in which a discharge is observed in the winding. Further, "measuring the first time zone" in the present invention is to calculate the difference between the time when the voltage or the current decreases after the increase and becomes zero and the time when the impulse voltage or the pulse voltage is applied. In addition to the mode obtained by the above, a mode of measuring using a timer or the like is preferably included.

As a result of diligent research, the present inventor has obtained a frequency spectrum obtained by Fourier transforming the first time-series voltage data observed at both ends of the winding or the first time-series current data flowing through the determination circuit. It has been found that a discharge is observed at a specific frequency component, and that there is a predetermined relationship between the impulse voltage or the pulse voltage and the discharge generation time. Based on the results of this study, the present invention is based on the first time-series voltage data or the first time-series current data detected by the detector, after the voltage or current has increased since the impulse voltage or pulse voltage was applied. The first time zone from the decrease to zero is measured, and the frequency spectrum of the frequency component peculiar to discharge in the frequency spectrum of the first time-series voltage data or the first time-series current data is inverse-Fourier-converted. The second time-series voltage data or the second time-series current data is acquired, and the first maximum voltage value or the first maximum current value in the first time zone of the second time-series voltage data or the second time-series current data is used. The first time from when the impulse voltage or the pulse voltage is applied until the first maximum voltage value or the first maximum current value is observed is obtained. Then, the applied impulse voltage or pulse voltage is applied to the first discharge estimation map in which the relationship between the impulse voltage or the pulse voltage and the discharge generation time is predetermined to set the first threshold range, and the first time corresponds to the first time. If it is within the first threshold range, it is estimated that a discharge is generated in the winding, and the first maximum voltage value or the first maximum current value is compared with the first threshold value. Then, if the first maximum voltage value or the first maximum current value is larger than the first threshold value, it is determined that the winding is discharged, and the first maximum voltage value or the first maximum current value is equal to or less than the first threshold value. If so, it is determined that no discharge has occurred in the winding. If the first time is outside the first threshold range, it is determined that no discharge has occurred in the winding.

That is, the magnitude of the impulse voltage or pulse voltage applied to the winding, the first maximum voltage value or the first maximum current value in the second time-series voltage data or the second time-series current data, and the impulse voltage or pulse voltage are applied. If the first time from the time when the first maximum voltage value or the first maximum current value is observed is known, whether or not a discharge has occurred in the winding using the first discharge estimation map. Estimates and judgments can be made. This makes it possible to more easily determine whether or not a discharge has occurred in the winding. In addition, before the inverse Fourier transform, the frequency component extractor extracts only the frequency components peculiar to the discharge from the frequency spectrum, that is, in order to make all the frequency spectra of the frequency components unrelated to the discharge zero, a special filter is used. No design is required and the calculation is extremely simple. As a result, the calculation time can be shortened. Further, since the configuration is such that the presence / absence of discharge is determined only when there is a possibility that discharge is generated in the winding, the determination can be made efficiently.

According to a further embodiment of the discharge determination device according to the present invention, a threshold value for setting the first threshold value by applying the first time to the first discharge determination map in which the relationship between the first time and the first threshold value is predetermined. It also has a setting unit.

According to this embodiment, it is possible to cope well with the case where the first threshold value changes according to the first time.

According to a further embodiment of the discharge determination device according to the present invention, the time zone measuring unit becomes zero voltage or current based on the first time-series voltage data or the first time-series current data detected by the detector. The second time zone from when the voltage or current increases or decreases and then decreases or increases until it becomes zero again is measured. In the second time-series voltage data or the second time-series current data, the feature amount extraction unit has the second maximum voltage value or maximum current value in the second time zone after the lapse of the first time zone, and the impulse voltage or pulse. The second time from the time when the voltage is applied until the second maximum voltage value or the second maximum current value is observed is obtained. Further, the estimation unit estimates that a discharge is generated in the winding if the first and / or the second time is within the first and / or the second threshold range, and the first and / or the second time If it is out of the first and / or second threshold range, it is determined that no discharge has occurred in the winding. Then, the determination unit is connected to the winding when the first maximum voltage value or the first maximum current value and / or the second maximum voltage value or the second maximum current value is larger than the first and / or the second threshold value. When it is determined that a discharge has occurred and the first maximum voltage value or the first maximum current value and / or the second maximum voltage value or the second maximum current value is equal to or less than the first and / or the second threshold value. It is determined that no discharge has occurred in the winding.

As a result of diligent research, the present inventor has found that discharge also occurs in the second time zone of the first time series voltage data or the first time series current data. Based on the results of this study, in this embodiment, in addition to the first maximum voltage value or the first maximum current value and the first time, the second maximum voltage value or the second maximum current value and the impulse voltage or the pulse voltage are applied. The second time from the time when the second maximum voltage value or the second maximum current value is observed is obtained, and the first time and / or the second time is within the first and / or second threshold range. If there is, it is estimated that a discharge has occurred in the winding, and the first maximum voltage value or the first maximum current value and / or the second maximum voltage value or the second maximum current value and the first and / or the first 2 Threshold and compare. Then, when the first maximum voltage value or the first maximum current value and / or the second maximum voltage value or the second maximum current value is larger than the first and / or the second threshold value, a discharge occurs in the winding. When the first maximum voltage value or the first maximum current value and / or the second maximum voltage value or the second maximum current value is equal to or less than the first and / or the second threshold value, the winding is discharged. It is determined that it has not occurred. If the first time and / or the second time is out of the first and / or second threshold range, it is determined that no discharge has occurred in the winding. As described above, according to the present embodiment, in order to determine whether or not a discharge has occurred not only in the first time zone but also in the second time zone, it is more reliable whether or not the winding has a discharge. It can be determined.

According to a further embodiment of the discharge determination device according to the present invention, the threshold value setting unit applies the second time to the second discharge determination map in which the relationship between the second time and the second threshold value is predetermined, and the second time is applied. Set the threshold.

According to this embodiment, it is possible to cope well with the case where the second threshold value changes according to the second time.

According to a further embodiment of the discharge determination device according to the present invention, the feature amount extraction unit obtains a second maximum voltage value or a second maximum current value and a second time for each second time zone.

According to this embodiment, in addition to the first time zone and the second time zone immediately after the first time zone, the second maximum voltage value or the second maximum current value and the second maximum current value are also performed in each of the subsequent second time zones. In addition to obtaining 2 hours, the first discharge estimation map is used to estimate and determine whether or not a discharge has occurred in the winding, so it is possible to determine whether or not a discharge has occurred in the winding. The determination can be made more reliably.

According to a further embodiment of the discharge determination device according to the present invention, the frequency component extraction unit extracts a frequency component larger than 5 MHz and less than 30 MHz as a frequency component peculiar to discharge from the frequency spectrum.

As a result of diligent research, the present inventor has found that the discharge signal can be satisfactorily detected by extracting only the frequency components of 5 MHz to 30 MHz and performing the inverse Fourier transform in the frequency spectrum. Based on the results of this research, in this embodiment, the frequency component peculiar to discharge is set to be larger than 5 MHz and less than 30 MHz. This makes it possible to reliably extract the discharge signal.

According to a preferred embodiment of the discharge determination method according to the present invention, a discharge determination method for determining whether or not a discharge is generated in a winding of an electric device is configured. In the discharge determination method, (a) an impulse voltage or a pulse voltage is applied across the winding, and (b) the first time-series voltage data observed at both ends of the winding, or a determination circuit including the winding. Detects the 1st time-series current data flowing in, and (c) based on the detected 1st time-series voltage data or 1st time-series current data, the voltage or current decreases after increasing from the time when the impulse voltage or pulse voltage is applied. The frequency spectrum is obtained by measuring the first time zone until it becomes zero, (d) Fourier transforming the detected first time-series voltage data or first time-series current data, and (e) from the frequency spectrum. The second time-series voltage data or the second time-series current data is obtained by extracting only the discharge-specific frequency component and (f) inverse Fourier transforming the frequency spectrum of the extracted discharge-specific frequency component, and (g) the first. The first maximum voltage value or the first maximum current value observed in the first time zone of the two time-series voltage data or the second time-series current data, and the maximum voltage value or the first maximum current after applying the impulse voltage. The first time until the value is observed is obtained, and (h) the applied impulse voltage or pulse voltage is applied to the first discharge estimation map in which the relationship between the impulse voltage or pulse voltage and the discharge generation time is predetermined. Then, the first threshold range is set, and (i) if the first time is within the first threshold range, it is estimated that a current is generated in the winding, and if the first time is outside the first threshold range, it is estimated. When it is determined that no discharge has occurred in the winding and it is estimated that a discharge has occurred in the winding by (j) step (i), the first maximum voltage value or the first maximum current value is used. By comparing with the first threshold value, it is determined that a discharge is generated in the winding when the first maximum voltage value or the first maximum current value is larger than the first threshold value, and the first maximum voltage value or the first maximum value is determined. When the current value is equal to or less than the first threshold value, it is determined that no discharge has occurred in the winding. Here, the "discharge-specific frequency component" in the present invention is defined as a specific frequency component in which a discharge is observed in the winding. Further, "measuring the first time zone" in the present invention is to calculate the difference between the time when the voltage or the current decreases after the increase and becomes zero and the time when the impulse voltage or the pulse voltage is applied. In addition to the mode obtained by the above, a mode of measuring using a timer or the like is preferably included.

As a result of diligent research, the present inventor has obtained a frequency spectrum obtained by Fourier transforming the first time-series voltage data observed at both ends of the winding or the first time-series current data flowing through the determination circuit. It has been found that a discharge is observed at a specific frequency component, and that there is a predetermined relationship between the impulse voltage or the pulse voltage and the discharge generation time. Based on the results of this study, the present invention is based on the first time-series voltage data or the first time-series current data detected by the detector, after the voltage or current has increased since the impulse voltage or pulse voltage was applied. The first time zone from the decrease to zero is measured, and the frequency spectrum of the frequency component peculiar to discharge in the frequency spectrum of the first time-series voltage data or the first time-series current data is inverse-Fourier-converted. The second time-series voltage data or the second time-series current data is acquired, and the first maximum voltage value or the first maximum current value in the first time zone of the second time-series voltage data or the second time-series current data is used. The first time from when the impulse voltage or the pulse voltage is applied until the first maximum voltage value or the first maximum current value is observed is obtained. Then, the applied impulse voltage or pulse voltage is applied to the first discharge estimation map in which the relationship between the impulse voltage or the pulse voltage and the discharge generation time is predetermined to set the first threshold range, and the first time corresponds to the first time. If it is within the first threshold range, it is estimated that a discharge is generated in the winding, and the first maximum voltage value or the first maximum current value is compared with the first threshold value. Then, if the first maximum voltage value or the first maximum current value is larger than the first threshold value, it is determined that the winding is discharged, and the first maximum voltage value or the first maximum current value is equal to or less than the first threshold value. If so, it is determined that no discharge has occurred in the winding. If the first time is outside the first threshold range, it is determined that no discharge has occurred in the winding.

That is, the magnitude of the impulse voltage or pulse voltage applied to the winding, the first maximum voltage value or the first maximum current value in the second time-series voltage data or the second time-series current data, and the impulse voltage or pulse voltage are applied. If the first time from the time when the first maximum voltage value or the first maximum current value is observed is known, whether or not a discharge has occurred in the winding using the first discharge estimation map. Estimates and judgments can be made. This makes it possible to more easily determine whether or not a discharge has occurred in the winding. In addition, before the inverse Fourier transform, the frequency component extractor extracts only the frequency components peculiar to the discharge from the frequency spectrum, that is, in order to make all the frequency spectra of the frequency components unrelated to the discharge zero, a special filter is used. No design is required and the calculation is extremely simple. As a result, the calculation time can be shortened. Further, since the configuration is such that the presence / absence of discharge is determined only when there is a possibility that discharge is generated in the winding, the determination can be made efficiently.

According to a further embodiment of the discharge determination method according to the present invention, a step of applying the first time to a first discharge determination map in which the relationship between the first time and the first threshold value is predetermined to set the first threshold value. (K) is further provided.

According to this embodiment, it is possible to cope well with the case where the first threshold value changes according to the first time.

According to a further embodiment of the discharge determination method according to the present invention, the step (c) starts from the time when the voltage or the current becomes zero based on the detected first time-series voltage data or the first time-series current data. It further includes the step of measuring the second time zone after the voltage or current increases or decreases and then decreases or increases until it reaches zero again. Further, in step (g), in the second time-series voltage data or the second time-series current data, the second maximum voltage value or the second maximum current value in the second time zone after the lapse of the first time zone and the impulse voltage are performed. Alternatively, it includes a step of obtaining a second time from the time when the pulse voltage is applied until the second maximum voltage value or the second maximum current value is observed. Further, in step (i), if the first and / or second time is within the first and / or second threshold range, it is estimated that the winding is discharged, and the first and / or second is performed. If the time is out of the first and / or second threshold range, it is a step of determining that no discharge has occurred in the winding. Then, step (j) is wound when the first maximum voltage value or the first maximum current value and / or the second maximum voltage value or the second maximum current value is larger than the first and / or the second threshold value. It is determined that a discharge has occurred in the wire, and the first maximum voltage value or the first maximum current value and / or the second maximum voltage value or the second maximum current value is equal to or less than the first and / or the second threshold value. At this time, it is a step to determine that no discharge has occurred in the winding.

As a result of diligent research, the present inventor has found that discharge also occurs in the second time zone of the first time series voltage data or the first time series current data. Based on the results of this study, in this embodiment, in addition to the first maximum voltage value or the first maximum current value and the first time, the second maximum voltage value or the second maximum current value and the impulse voltage or the pulse voltage are applied. The second time from the time when the second maximum voltage value or the second maximum current value is observed is obtained, and the first time and / or the second time is within the first and / or second threshold range. If there is, it is estimated that a discharge has occurred in the winding, and the first maximum voltage value or the first maximum current value and / or the second maximum voltage value or the second maximum current value and the first and / or the first 2 Threshold and compare. Then, when the first maximum voltage value or the first maximum current value and / or the second maximum voltage value or the second maximum current value is larger than the first and / or the second threshold value, a discharge occurs in the winding. When the first maximum voltage value or the first maximum current value and / or the second maximum voltage value or the second maximum current value is equal to or less than the first and / or the second threshold value, the winding is discharged. It is determined that it has not occurred. If the first time and / or the second time is out of the first and / or second threshold range, it is determined that no discharge has occurred in the winding. As described above, according to the present embodiment, in order to determine whether or not a discharge has occurred not only in the first time zone but also in the second time zone, it is more reliable whether or not the winding has a discharge. It can be determined.

According to a further embodiment of the discharge determination device according to the present invention, in step (k), the second time is applied to the second discharge determination map in which the relationship between the second time and the second threshold value is predetermined. 2 Set the threshold.

According to this embodiment, it is possible to cope well with the case where the second threshold value changes according to the second time.

According to a further embodiment of the discharge determination method according to the present invention, step (f) further includes a step of obtaining a second maximum voltage value or a second maximum current value and a second time for each second time zone. Includes.

According to this embodiment, in addition to the first time zone and the second time zone immediately after the first time zone, the second maximum voltage value or the second maximum current value and the second maximum current value are also performed in each of the subsequent second time zones. In addition to obtaining 2 hours, the second discharge estimation map is used to estimate and determine whether or not a discharge has occurred in the winding, so it is possible to determine whether or not a discharge has occurred in the winding. The determination can be made more reliably.

According to a further embodiment of the discharge determination method according to the present invention, step (e) is a step of extracting a frequency component larger than 5 MHz and less than 30 MHz as a frequency component peculiar to discharge from the frequency spectrum.

As a result of diligent research, the present inventor has found that the discharge signal can be satisfactorily detected by extracting only the frequency components of 5 MHz to 30 MHz and performing the inverse Fourier transform in the frequency spectrum. Based on the results of this research, in this embodiment, the frequency component peculiar to discharge is set to be larger than 5 MHz and less than 30 MHz. This makes it possible to reliably extract the discharge signal.

According to a preferred embodiment of the program according to the present invention, a program for determining whether or not a discharge is generated in the winding of an electric device is configured. The program is for causing one or more computers to execute each step of the discharge determination method according to the present invention in any of the above-described embodiments. The program may be recorded on a computer-readable recording medium such as a hard disk, ROM, SSD, flash memory (USB memory, SD card, etc.), floppy disk, CD, DVD, or a transmission medium. For example, it may be delivered from one computer to another computer via a communication network such as the Internet or a LAN, or may be exchanged in any other manner.

According to the present invention, by causing one computer to execute the program or by having a plurality of computers execute each step in a shared manner, each step of the discharge determination method according to the present invention in any of the above-described embodiments is executed. Therefore, the same operation and effect as the discharge determination method according to the present invention described above, for example, the effect of being able to more easily determine whether or not a discharge is generated in the winding, and shortening the calculation time can be achieved. It is possible to obtain an effect such as being able to plan, an effect such as being able to make an efficient determination, and the like.

According to the present invention, it is possible to more easily determine whether or not a discharge has occurred.

It is a block diagram which shows the outline of the structure of the discharge determination device 1 which concerns on embodiment of this invention. It is a flowchart which shows an example of the discharge generation determination processing executed by the discharge determination apparatus 1. In the explanatory diagram showing the result of acquiring the second time series voltage data by extracting only the frequency component peculiar to discharge and performing the inverse Fourier transform after converting the first time series voltage data into a frequency spectrum by Fourier transform. be. This is the experimental result of acquiring the second time series voltage data by swinging the frequency band in order to determine the frequency component peculiar to the discharge. It is explanatory drawing which shows the mode that the maximum voltage value Vmax1 and the 1st time T1 are measured from the 2nd time series voltage data. It is explanatory drawing which shows an example of the 1st discharge estimation map. In the explanatory diagram showing the result of acquiring the second time series voltage data by extracting only the frequency component peculiar to discharge and performing the inverse Fourier transform after converting the first time series voltage data into a frequency spectrum by Fourier transform. be. It is a flowchart which shows another example of the discharge generation determination processing executed by the discharge determination apparatus 1. It is explanatory drawing which shows the mode that the maximum voltage values Vmax1, Vmax2, and the 1st and 2nd time T1, T2 are measured from the 2nd time series voltage data. It is explanatory drawing which shows an example of the 2nd discharge estimation map. It is explanatory drawing which shows an example of the threshold value setting map for setting the 1st threshold value Vth1. It is explanatory drawing which shows an example of the threshold value setting map for setting the 2nd threshold value Vth2.

Next, the best mode for carrying out the present invention will be described with reference to examples.

The discharge determination device 1 according to the embodiment of the present invention is configured as a device for diagnosing whether or not a discharge is generated in the winding 20 of an electric device such as a rotating machine such as a motor or a generator and an electric device such as a transformer. ing. As shown in FIG. 1, the discharge determination device 1 includes terminals Te1 and Te2 to which the winding 20 is connected, and an impulse voltage generation circuit electrically connected to the terminals Te1 and Te2 via power lines L1 and L2. 2, the voltage measuring unit 4 and the current measuring unit 5 electrically connected to the power lines L1 and L2, and the A / D conversion circuit 6 electrically connected to the voltage measuring unit 4 and the current measuring unit 5. The display unit 8 for displaying the diagnosis result and the electronic control unit 10 for controlling the entire device are provided.

The impulse voltage generation circuit 2 is a circuit capable of applying an impulse voltage Vi having a predetermined characteristic to the winding 20. The voltage measuring unit 4 measures the voltage V observed at both ends of the winding 20 when the impulse voltage Vi is applied to the winding 20 connected to the terminals Te1 and Te2. Further, the current measuring unit 5 measures the current I flowing through the measuring circuit 30 when the impulse voltage Vi is applied to the windings 20 connected to the terminals Te1 and Te2. The A / D conversion circuit 6 converts the analog signal of the voltage V measured by the voltage measuring unit 4 and the current I measured by the current measuring unit 5 into a digital signal and outputs the analog signal to the electronic control unit 10. The voltage measuring unit 4 corresponds to the "detector" in the present invention, and the measuring circuit 30 is an example of an implementation configuration corresponding to the "determination circuit" in the present invention.

As shown in FIG. 1, the electronic control unit 10 is configured as a microprocessor centered on a CPU 12, and includes a ROM 14 that stores a processing program in addition to the CPU 12, and a RAM 16 that temporarily stores data, which is not shown. It has an input / output port and a communication port. The voltage V, current I, and the like from the A / D conversion circuit 6 are input to the electronic control unit 10 via an input port (not shown). Further, the electronic control unit 10 outputs an impulse voltage application signal to the impulse voltage generation circuit 2 and a diagnosis result display signal to the display unit 8 via an output port (not shown).

Next, the operation of the discharge determination device 1 according to the embodiment of the present invention configured in this way, particularly the operation for diagnosing whether or not a discharge is generated in the winding 20 will be described. FIG. 2 is a flowchart showing an example of the discharge generation determination process executed by the discharge determination device 1. This process is executed when the winding 20 to be diagnosed is connected to the terminals Te1 and Te2 and the determination start is instructed (for example, when the determination start button is pressed). The discharge generation determination process is an example of an implementation configuration corresponding to the "program" in the present invention.

When the discharge generation determination process is executed, the CPU 12 of the discharge determination device 1 first outputs an impulse voltage application signal to the impulse voltage generation circuit 2 so as to apply the impulse voltage Via to the winding 20 (step S100). .. Subsequently, a process of reading the applied impulse voltage Via and the first time-series voltage data (FIG. 3A) relating to the voltage V across the winding 20 measured by the voltage measuring unit 4 is executed (step). S102), based on the read first time-series voltage data, a process of measuring the first discharge generation estimated time zone Rt1 is executed (step S104). Here, as a result of diligent research by the present inventor, when the impulse voltage Via is applied to the winding 20, the voltage V across the winding 20 measured by the voltage measuring unit 4 increases and then decreases, and the value becomes zero. It was found that the discharge occurs in the first discharge generation estimated time zone Rt1 which is the time zone until the voltage becomes. Based on the results of this research, in the present embodiment, the first discharge generation estimated time zone Rt1 is the time when the voltage V across the winding 20 increases and then decreases to zero, and the impulse voltage Via. The configuration was determined by the difference between the time when the application was applied and the time. The first discharge generation estimated time zone Rt1 corresponds to the "first time zone" in the present invention, and in step S104, the electronic control unit 10 that executes the process of measuring the discharge generation estimated time zone Rt1 is the "time" in the present invention. This is an example of an implementation configuration corresponding to the "band measurement unit".

Subsequently, a process of converting the first time-series voltage data, which is a time-series signal, into a frequency spectrum (FIG. 3B) by Fourier transform is executed (step S106). Note that FIG. 3A is a diagram showing the first time-series voltage data measured by the voltage measuring unit 4, and FIG. 3B is obtained by Fourier transforming the first time-series voltage data. It is a figure which shows the frequency spectrum. Here, in step S106, the electronic control unit 10 that executes a process of converting the first time-series voltage data, which is a time-series signal, into a frequency spectrum by Fourier transforming the first time-series voltage data, is the "Fourier" in the present invention. This is an example of an implementation configuration corresponding to the “conversion unit”.

Then, only the frequency component peculiar to the discharge is extracted from the converted frequency spectrum (step S108), and the frequency spectrum of the extracted frequency component (FIG. 3 (c)) is subjected to the inverse Fourier transform to obtain a second time series which is a time series signal. A process of converting to voltage data (FIG. 3 (d)) is executed (step S110). Here, the frequency peculiar to discharge is set to a frequency of 5 to 30 MHz in the present embodiment. This is due to the fact that as a result of diligent research by the present inventor, it has been found that the frequency component in the band of 5 to 30 MHz detects the discharge signal well. In the second time-series voltage data obtained by extracting the frequency components in the band of 5 to 30 MHz and performing the inverse Fourier transform, waveforms including the discharge signal were observed as shown in FIGS. 4 (c) to 4 (g). On the other hand, in the second time-series voltage data obtained by extracting the frequency components in the band other than 5 to 30 MHz and performing the inverse Fourier transform, as shown in FIGS. 4A, 4B, and 4H. , The waveform including the discharge signal was not clearly observed. Based on this result, the frequency spectra of frequency components not related to discharge are all set to zero. Note that FIG. 3 (c) is a diagram in which only the frequency component peculiar to discharge is extracted from the frequency spectrum of the first time series voltage data, and FIG. 3 (d) is an inverse Fourier transform of the data in FIG. 3 (c). It is a figure which shows the 2nd time series voltage data obtained by this. Here, in step S108, the electronic control unit 10 that executes the process of extracting only the frequency component peculiar to the discharge from the frequency spectrum corresponds to the "frequency extraction unit" in the present invention, and the frequency component extracted in step S110. The electronic control unit 10 that executes the process of converting the frequency spectrum into the second time series voltage data by the inverse Fourier transform is an example of the embodiment corresponding to the "inverse Fourier transform unit" in the present invention.

When the second time-series voltage data is obtained in this way, the CPU 12 of the discharge determination device 1 determines the maximum voltage value observed in the first discharge generation estimated time zone Rt1 of the second time-series voltage data, as shown in FIG. A process of measuring Vmax1 and the first time T1 from the time when the impulse voltage Via is applied until the maximum voltage value Vmax1 is observed is executed (step S112), and the first time T1 is the first threshold range. A process of determining whether or not it is within (Tth1 ≦ T1 ≦ Tth2) is executed (step S114). In step S112, the electronic control unit 10 that executes the process of measuring the maximum voltage value Vmax1 and the first time T1 from the second time series voltage data has an implementation configuration corresponding to the "feature amount extraction unit" in the present invention. This is just one example.

Here, in the present embodiment, as shown in FIG. 6, the first threshold range is set in the ROM 14 as the first discharge estimation map by obtaining the relationship between the impulse voltage Vi and the discharge generation time T * in advance by an experiment. It is stored, and when the applied impulse voltage Via and the first time T1 are given, the first threshold range (Tth1 ≦ T1 ≦ Tth2) corresponding to the impulse voltage Via is set. The first discharge estimation map has a tendency that the discharge generation time T * decreases as the impulse voltage Vi increases. In step S114, the electronic control unit 10 that executes a process of setting a first threshold range (Tth1 ≦ T1 ≦ Tth2) corresponding to the impulse voltage Via when the applied impulse voltage Via and the first time T1 are given. Is an example of an implementation configuration corresponding to the "threshold range setting unit" in the present invention.

In the present embodiment, if the first time T1 is within the first threshold range (Tth1 ≦ T1 ≦ Tth2), it is estimated that the winding 20 is discharged, while the first time T1 is the first. When it is out of one threshold range (Tth1 ≧ T1, T1 ≧ Tth2), it is determined that no discharge has occurred in the winding 20. The electronic control unit 10 that executes a process of estimating whether or not the first time T1 is within the first threshold value range (Tth1 ≦ T1 ≦ Tth2), that is, whether or not a discharge is generated in the winding 20 , Is an example of an implementation configuration corresponding to the "estimation unit" in the present invention.

In step S114, when it is estimated that the first time T1 is within the first threshold range (Tth1 ≦ T1 ≦ Tth2), that is, a discharge is generated in the winding 20, the maximum voltage value Vmax1 is subsequently estimated. Is larger than the first threshold value Vth1 (step S116). In the determination, when it is determined that the maximum voltage value Vmax1 is larger than the first threshold value Vth1, it is determined that the winding 20 is discharged, and "discharge generation" indicating that the discharge is generated is performed. Output (step S118) and end this routine. In the present embodiment, the first threshold value Vth1 is configured to obtain the relationship between the maximum voltage value Vmax1 and the generation of discharge by an experiment in advance and store it in the ROM 14.

On the other hand, when it is determined in step S114 that the first time T1 is out of the first threshold range (Tth1 ≧ T1, T1 ≧ Tth2), or in step S116, the maximum voltage value Vmax1 is equal to or less than the first threshold value Vth1. When it is determined that there is, it is determined that no discharge has occurred in the winding 20, and "no discharge" is output (step S120), and this routine is terminated. That is, in the present embodiment, first, it is estimated whether or not a discharge is generated in the winding 20 (step S114), and only when it is estimated that a discharge is generated in the winding 20 (winding). Only when there is a possibility that a discharge has occurred in 20), it is determined whether or not the estimation is correct. As a result, it is possible to efficiently determine whether or not a discharge is generated in the winding 20. The electronic control unit 10 that executes a process of determining whether or not a discharge is generated in the winding 20 is an example of an implementation configuration corresponding to the “determination unit” in the present invention.

According to the discharge determination device 1 of the present invention according to the present embodiment described above, the impulse voltage Via is applied to both ends of the winding 20 (step S100), and the first time series observed at both ends of the winding 20 is observed. The first discharge generation estimated time zone Rt1 is measured based on the voltage data (step S104), the frequency spectrum is obtained by Fourier transforming the first time-series voltage data (steps S104 to S106), and the discharge is performed from the frequency spectrum. Only the peculiar frequency component is extracted (step S108), and the frequency spectrum of the extracted frequency component peculiar to the discharge is inverse Fourier transformed to obtain the second time-series voltage data (step S110). Subsequently, the maximum voltage value Vmax1 and the first time T1 from the time when the impulse voltage Via is applied to the time when the maximum voltage value Vmax1 is shown are obtained from the first discharge generation estimated time zone Rt1 of the second time series voltage data. (Step S112). Then, if the first time T1 is within the first threshold range (Tth1 ≦ T1 ≦ Tth2) set by using the first discharge estimation map, it is estimated that the winding 20 is discharged (step S114). ), When the maximum voltage value Vmax1 is larger than the first threshold value Vth1, it is determined that the winding 20 is discharged (steps S116 to S118). On the other hand, when the first time T1 is outside the first threshold range (Tth1 ≧ T1, T1 ≧ Tth2), or when the maximum voltage value Vmax1 is equal to or less than the first threshold Vth1, a discharge occurs in the winding 20. It is determined that this is not done (step S120).

That is, according to the discharge determination device 1 of the present invention according to the present embodiment, the magnitude of the impulse voltage Via applied to the winding 20, the maximum voltage value Vmax1 in the second time series voltage data, and the impulse voltage Via are applied. If the first time T1 from that time to the time when the maximum voltage value Vmax1 is shown is known, it is possible to estimate and determine whether or not a discharge is generated in the winding 20. This makes it possible to more easily determine whether or not a discharge is generated in the winding 20.

Further, since the frequency spectrum of the frequency component not related to the discharge is set to zero before the inverse Fourier transform, the design of a special filter becomes unnecessary and the calculation becomes extremely simple. As a result, the calculation time can be shortened. Further, first, it is estimated whether or not the winding 20 may have a discharge, and only when it is estimated that the winding 20 may have a discharge, the presence or absence of the discharge occurs. Since the determination is made, the determination can be made efficiently.

In the present embodiment, the presence or absence of discharge generation is estimated and determined using the maximum voltage value Vmax1 and the first time T1, but the present invention is not limited to this. For example, in addition to the maximum voltage value Vmax1 and the first time T1, the second maximum voltage value Vmax2 observed in the second discharge generation estimated time zone Rt2 and the time until the second maximum voltage value Vmax2 is shown. The presence or absence of discharge may be estimated and determined using T2 for 2 hours.

Here, as shown in FIG. 7A, the second discharge generation estimated time zone Rt2 is a time zone generated immediately after the first discharge generation estimated time zone Rt1, and is measured by the voltage measuring unit 4. It is defined as a time zone from when the voltage V across the winding 20 reaches zero value, after it decreases, and then increases until the value becomes zero again. As a result of diligent research, the present inventor has found that discharge occurs even within the second discharge generation estimated time zone Rt2. The second discharge generation estimated time zone Rt2 is an example of the implementation configuration corresponding to the “second time zone” in the present invention.

In this case, the discharge generation determination process shown in FIG. 8 can be executed instead of the flowchart showing an example of the discharge generation determination process shown in FIG. The discharge generation determination process shown in FIG. 8 merely replaces steps S104, S112, S114, and S116 of the discharge generation determination process shown in FIG. 2 with steps S204, S212, S214, and S216, respectively.

That is, in the discharge generation determination process shown in FIG. 8, the CPU 12 of the discharge determination device 1 first outputs an impulse voltage application signal to the impulse voltage generation circuit 2 so as to apply the impulse voltage Via to the winding 20 (step). S100), the first time-series voltage data (FIG. 7A) regarding the applied impulse voltage Via and the voltage V across the winding 20 measured by the voltage measuring unit 4 is read (step S102), and the read first. Based on the time-series voltage data, the process of measuring the first and second discharge generation estimated time zones Rt1 and Rt2 is executed (step S204).

Subsequently, the first time-series voltage data is converted into a frequency spectrum (FIG. 7 (b)) by Fourier transform, and the first time-series voltage data, which is a time-series signal, is converted into a frequency spectrum (step S106), and the converted frequency spectrum is unique to discharge. (Step S108), the frequency spectrum of the extracted frequency component (FIG. 7 (c)) is subjected to the inverse Fourier transform to obtain the frequency spectrum of the second time-series voltage data (FIG. 7 (FIG. 7)). d) Execute the process of converting to) (step S110).

Then, as shown in FIG. 9, the maximum voltage values Vmax1 and Vmax2 in the first and second discharge generation estimated time zones Rt1 and Rt2 of the second time-series voltage data and the maximum from the time when the impulse voltage Via is applied. The process of measuring the first and second time T1 and T2 until the voltage values Vmax1 and Vmax2 are observed is executed (step S212), and the first time T1 is within the first threshold range (Tth1 ≦ T1 ≦ Tth2). ), And whether or not the second time T2 is within the second threshold range (Tth3 ≦ T2 ≦ Tth4) is executed (step S214).

Here, in the second threshold range, as shown in FIG. 10, in the modified example, the relationship between the impulse voltage Vi and the discharge generation time T * is obtained in advance by experiments, as in the setting of the first discharge estimation map. The second discharge estimation map is stored in the ROM 14, and when the applied impulse voltage Via and the second time T2 are given, the second threshold range (Tth3 ≦ T2 ≦ Tth4) corresponding to the impulse voltage Via is set. The configuration was set. Similar to the first discharge estimation map, the second discharge estimation map has a tendency that the discharge generation time T * decreases as the impulse voltage Vi increases. In step S212, the process of measuring the maximum voltage values Vmax1 and Vmax2 and the first and second time T1 and T2 in the first and second discharge occurrence estimated time zones Rt1 and Rt2 of the second time series voltage data is performed. The electronic control unit 10 to be executed is an example of an implementation configuration corresponding to the "feature amount extraction unit" in the present invention. Further, in step S214, when the applied impulse voltage Via and the first and second time T1 and T2 are given, the first and second threshold ranges (Tth1 ≦ T1 ≦ Tth2, corresponding to the impulse voltage Via, The electronic control unit 10 that executes the process of setting Tth3 ≦ T2 ≦ Tth4) is an example of the implementation configuration corresponding to the “threshold range setting unit” in the present invention.

In the determination, if the first time T1 is within the first threshold range (Tth1 ≦ T1 ≦ Tth2) or the second time T2 is within the second threshold range (Tth3 ≦ T2 ≦ Tth4), the winding 20 is discharged. Is presumed to occur, but if the first time T1 is out of the threshold range (Tth1 ≧ T1, T1 ≧ Tth2) and the second time T2 is out of the threshold range (Tth3 ≧ T2, T2 ≧ Tth4). , It is determined that no discharge has occurred in the winding 20.

Then, in step S214, the first time T1 is within the first threshold range (Tth1 ≦ T1 ≦ Tth2), or the second time T2 is within the second threshold range (Tth3 ≦ T2 ≦ Tth4), that is, the winding. When it is estimated that a discharge is generated at 20, it is determined whether or not the maximum voltage value Vmax1 is larger than the first threshold value Vth1 and whether or not the maximum voltage value Vmax2 is larger than the second threshold value Vth2 (. In step S216), when it is determined that the maximum voltage value Vmax1 is larger than the first threshold value Vth1 or the maximum voltage value Vmax2 is larger than the second threshold value Vth2, it is determined that the winding 20 is discharged. “Discharge generation” indicating that discharge has occurred is output (step S118), and this routine is terminated. In the modified example, the second threshold value Vth2 is configured to obtain the relationship between the maximum voltage value Vmax2 and the generation of discharge by an experiment in advance and store it in the ROM 14.

On the other hand, in step S214, the first time T1 is out of the first threshold range (Tth1 ≧ T1, T2, T1, T2 ≧ Tth2), and the second time T2 is out of the second threshold range (Tth3 ≧ T2, T2 ≧ Tth4). ), Or when it is determined in step S216 that the maximum voltage value Vmax1 is equal to or less than the first threshold value Vth1 and the maximum voltage value Vmax2 is equal to or less than the second threshold value Vth2, a discharge occurs in the winding 20. It is determined that this is not the case, "no discharge" is output (step S120), and this routine is terminated.

According to the modification described above, the operation and effect similar to the operation and effect of the discharge determination device 1 according to the above-described embodiment are obtained, and the second discharge generation estimation is performed in addition to the first discharge generation estimation time zone Rt1. Since it is determined whether or not a discharge is generated even in the time zone Rt2, it is possible to more reliably determine whether or not a discharge is generated in the winding 20.

In the modification described above, the presence or absence of discharge generation is determined only in the first discharge generation estimated time zone Rt1 and the second discharge generation estimated time zone Rt2 that occurs immediately after the first discharge generation estimated time zone Rt1. , Not limited to this. For example, the configuration may be such that the presence or absence of discharge generation is determined for each subsequent second discharge generation estimated time zone Rt2, that is, for each time zone in which peaks and valleys occur in the waveform of the first time series voltage data. In this case, it is desirable to prepare a discharge estimation map for each second discharge generation estimation time zone Rt2.

In the present embodiment and the above-described modification, the first time-series voltage data and the second time-series voltage data regarding the voltage V are used, but the first time-series current data and the second time-series current data regarding the current I are used. May be. In this case, the maximum current values Imax1 and Imax2 may be used instead of the maximum voltage values Vmax1 and Vmax2 to determine the presence or absence of discharge.

In the present embodiment and the above-described modifications, the first time T1 is within the first threshold range (Tth1 ≦ T1 ≦ Tth2), or the second time T2 is within the second threshold range (Tth3 ≦ T2 ≦ Tth4). For example, it is estimated that a discharge is generated in the winding 20, but the present invention is not limited to this. For example, when the first time T1 is within the first threshold range (Tth1 ≦ T1 ≦ Tth2) and the second time T2 is within the second threshold range (Tth3 ≦ T2 ≦ Tth4), a discharge occurs in the winding 20. You may presume that you are doing it.

In the present embodiment and the above-described modification, the winding 20 is discharged when the maximum voltage value Vmax1 is larger than the first threshold value Vth1 or when the maximum voltage value Vmax2 is larger than the second threshold value Vth2. However, it is not limited to this. For example, when the maximum voltage value Vmax1 is larger than the first threshold value Vth1 and the maximum voltage value Vmax2 is larger than the second threshold value Vth2, it may be determined that the winding 20 is discharged.

In the present embodiment and the above-mentioned modifications, the first and second threshold values Vth1 and Vth2 are set to constant values, but the present invention is not limited to this. For example, as shown in FIGS. 11 and 12, the first and second threshold values Vth1 and Vth2 may be configured to change according to the discharge generation time T *. In this case, the first and second threshold values Vth1 and Vth2 can be set according to the discharge generation time T * by using the maps shown in FIGS. 11 and 12. Here, the electronic control unit 10 that executes the process of setting the first and second threshold values Vth1 and Vth2 is an example of the implementation configuration corresponding to the "threshold value setting unit" in the present invention.

In the present embodiment and the above-described modification, the impulse voltage Via is applied to the winding 20, but the present invention is not limited to this. For example, a configuration in which a pulse voltage or an AC voltage is applied to the winding 20 may be used.

The present embodiment shows an example of the embodiment for carrying out the present invention. Therefore, the present invention is not limited to the configuration of the present embodiment.

1 Discharge judgment device (discharge judgment device)
2 Applied voltage generation circuit (applied voltage generation circuit)
4 Voltage measuring unit (detector)
5 Current measuring unit (detector)
6 A / D conversion circuit 8 Display unit 10 Electronic control unit 12 CPU
14 ROM
16 RAM
20 windings (windings)
30 Measurement circuit (judgment circuit)
V voltage (voltage observed across the winding)
Vi impulse voltage (impulse voltage)
Via applied impulse voltage (impulse voltage)
Vmax1 maximum voltage value (first maximum voltage value)
Vmax2 maximum voltage value (second maximum voltage value)
Imax1 maximum current value (first maximum current value)
Imax maximum current value (second maximum current value)
Rt1 1st discharge generation estimated time zone (1st time zone)
Rt2 Second discharge generation estimated time zone (second time zone)
Te1 terminal Te2 terminal L1 power line L2 power line T1 1st hour (1st hour)
T2 2nd hour (2nd hour)
Lower limit of Tth1 first threshold range (first threshold range)
Tth2 Upper limit of the first threshold range (first threshold range)
Vth1 1st threshold (1st threshold)
Tth3 Lower limit of the second threshold range (second threshold range)
Tth4 Upper limit of the second threshold range (second threshold range)
Vth2 2nd threshold (2nd threshold)

Claims (13)

It is a discharge judgment device that determines whether or not a discharge has occurred in the winding of an electric device.
An applied voltage generation circuit connected to both ends of the winding so that an impulse voltage or a pulse voltage can be applied to both ends of the winding.
In order to detect the first time-series voltage data observed at both ends of the winding, or the first time-series current data flowing in the determination circuit including the winding and the applied voltage generation circuit, the determination circuit is used. With the connected detector,
Based on the first time-series voltage data or the first time-series current data detected by the detector, from the time when the impulse voltage or pulse voltage is applied until the voltage or current decreases after increasing to zero. The time zone measurement unit that measures the first time zone of
A Fourier transform unit that obtains a frequency spectrum by Fourier transforming the first time-series voltage data or the first time-series current data detected by the detector.
A frequency component extractor that extracts only the frequency components peculiar to discharge from the frequency spectrum,
An inverse Fourier transform unit that obtains a second time-series voltage data or a second time-series current data by inverse Fourier transforming the frequency spectrum of the extracted frequency component peculiar to the discharge.
From the time when the first maximum voltage value or the first maximum current value observed in the first time zone of the second time-series voltage data or the second time-series current data and the impulse voltage or the pulse voltage are applied. A feature quantity extraction unit for obtaining the first time until the first maximum voltage value or the first maximum current value is observed, and
Threshold range setting for setting the first threshold range by applying the applied impulse voltage or pulse voltage to the first discharge estimation map in which the relationship between the impulse voltage or the pulse voltage and the discharge generation time is predetermined. Department and
If the first time is within the first threshold range, it is estimated that a discharge is generated in the winding, and if the first time is outside the first threshold range, a discharge is generated in the winding. The estimation unit that determines that it is not, and
When it is estimated by the estimation unit that a discharge is generated in the winding, the first maximum voltage value or the first maximum current value is compared with the first threshold value, and the first maximum voltage value is compared. Alternatively, when the first maximum current value is larger than the first threshold value, it is determined that a discharge is generated in the winding, and the first maximum voltage value or the first maximum current value is equal to or lower than the first threshold value. Sometimes, a determination unit that determines that no discharge has occurred in the winding, and
Discharge determination device. The first aspect of claim 1, further comprising a threshold value setting unit for setting the first threshold value by applying the first time to the first discharge determination map in which the relationship between the first time and the first threshold value is predetermined. Discharge judgment device. Based on the first time-series voltage data or the first time-series current data detected by the detector, the time zone measuring unit receives the voltage or the current from the time when the voltage or the current becomes zero. Measure the second time zone from increase or decrease to decrease or increase to zero again,
In the second time-series voltage data or the second time-series current data, the feature amount extraction unit uses the second maximum voltage value or the second maximum current value in the second time zone after the lapse of the first time zone. , The second time from when the impulse voltage or the pulse voltage is applied until the second maximum voltage value or the second maximum current value is shown.
The threshold range setting unit applies the applied impulse voltage or pulse voltage to the second discharge estimation map in which the relationship between the impulse voltage or the pulse voltage and the discharge generation time is predetermined. Set the threshold range and
The estimation unit estimates that a discharge has occurred in the winding if the first and / or second time is within the first and / or second threshold range, and the first and / or second If the two hours are outside the first and / or second threshold range, it is determined that no discharge has occurred in the winding.
The determination unit receives when the first maximum voltage value or the first maximum current value and / or the second maximum voltage value or the second maximum current value is larger than the first and / or the second threshold value. It is determined that a discharge is generated in the winding, and the first maximum voltage value or the first maximum current value and / or the second maximum voltage value or the second maximum current value is the first. The discharge determination device according to claim 1 or 2, wherein it is determined that no discharge is generated in the winding when the voltage is 1 and / or the second threshold value or less. The threshold value setting unit is dependent on claim 2 for setting the second threshold value by applying the second time to the second discharge determination map in which the relationship between the second time and the second threshold value is predetermined. The discharge determination device according to claim 3. The discharge determination device according to claim 3 or 4, wherein the feature amount extraction unit obtains the second maximum voltage value or the second maximum current value and the second time for each of the second time zones. The discharge determination device according to any one of claims 1 to 5, wherein the frequency component extraction unit extracts a frequency component larger than 5 MHz and less than 30 MHz as the frequency component peculiar to the discharge from the frequency spectrum. It is a discharge determination method that determines whether or not a discharge has occurred in the winding of an electric device.
(A) An impulse voltage or a pulse voltage is applied to both ends of the winding, and the pulse voltage is applied.
(B) The first time-series voltage data observed at both ends of the winding or the first time-series current data flowing through the determination circuit including the winding is detected.
(C) Based on the detected first time-series voltage data or the first time-series current data, the first from the time when the impulse voltage or the pulse voltage is applied until the voltage or the current decreases after increasing and becomes zero. Measure the time zone,
(D) The frequency spectrum is obtained by Fourier transforming the detected first time-series voltage data or the first time-series current data.
(E) Only the frequency component peculiar to the discharge is extracted from the frequency spectrum, and the frequency component is extracted.
(F) The second time-series voltage data or the second time-series current data is obtained by inverse Fourier transforming the frequency spectrum in the extracted frequency component peculiar to the discharge.
(G) The first maximum voltage value or the first maximum current value observed in the first time zone of the second time-series voltage data or the second time-series current data, and the impulse voltage or the pulse voltage are applied. The first time from the time when the first maximum voltage value or the first maximum current value is observed is obtained.
(H) The applied impulse voltage or pulse voltage is applied to the first discharge estimation map in which the relationship between the impulse voltage or the pulse voltage and the discharge generation time is predetermined to set the first threshold range.
(I) If the first time is within the first threshold range, it is estimated that a discharge is generated in the winding, and if the first time is outside the first threshold range, the winding is discharged. Is not generated, and
(J) When it is estimated that a discharge is generated in the winding by the step (i), the first maximum voltage value or the first maximum current value is compared with the first threshold value. When the first maximum voltage value or the first maximum current value is larger than the first threshold value, it is determined that a discharge is generated in the winding, and the first maximum voltage value or the first maximum current value is determined. A discharge determination method for determining that no discharge has occurred in the winding when the voltage is equal to or less than the first threshold value. The seventh aspect of claim 7 further comprises a step (k) of applying the first time to set the first threshold value on the first discharge determination map in which the relationship between the first time and the first threshold value is predetermined. Discharge judgment method. The step (c) is based on the detected first time-series voltage data or the first time-series current data, and the voltage or the current decreases after the voltage or the current increases or decreases from the time when the voltage or the current becomes zero. Or it further includes a step to measure the second time zone from increasing to zero again.
The step (g) is the second maximum voltage value or the second maximum current value in the second time zone after the lapse of the first time zone in the second time series voltage data or the second time series current data. , A second time from when the impulse voltage or the pulse voltage is applied until the second maximum voltage value or the second maximum current value is shown, and includes a step of obtaining.
In the step (h), the applied impulse voltage or the pulse voltage is applied to the second discharge estimation map in which the relationship between the impulse voltage or the pulse voltage and the discharge generation time is predetermined, and the second threshold value is applied. Set the range and
In step (i), if the first and / or second time is within the first and / or second threshold range, it is estimated that a discharge is generated in the winding, and the first and / or the first and / or Alternatively, if the second time is outside the first and / or second threshold range, it is a step of determining that no discharge has occurred in the winding.
In step (j), the first maximum voltage value or the first maximum current value and / or the second maximum voltage value or the second maximum current value is from the first and / or the second threshold value. When it is large, it is determined that a discharge is generated in the winding, and the first maximum voltage value or the first maximum current value and / or the second maximum voltage value or the second maximum current value is determined. The discharge determination method according to claim 7 or 8, which is a step of determining that no discharge has occurred in the winding when the voltage is equal to or less than the first and / or second threshold. The step (k) includes a step of applying the second time to set the second threshold value on the second discharge determination map in which the relationship between the second time and the second threshold value is predetermined. The discharge determination device according to claim 9, which is subordinate to claim 8. The ninth or tenth aspect of the present invention, wherein the step (f) further includes a step of obtaining the second maximum voltage value or the second maximum current value and the second time for each of the second time zones. Discharge judgment method. The discharge determination method according to any one of claims 7 to 11, wherein step (e) is a step of extracting a frequency component larger than 5 MHz and less than 30 MHz as the frequency component peculiar to the discharge from the frequency spectrum. It is a program for determining whether or not an electric discharge is occurring in the winding of an electric device.
A program for causing one or more computers to execute each step of the discharge determination method according to any one of claims 7 to 12.

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