JP2017219537A - Discharge monitoring device and discharge monitoring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a discharge monitoring device and a discharge monitoring method that can reduce an amount of data used for discharge monitoring and can monitor discharge for a long time.SOLUTION: A discharge monitoring device (1) of the present invention includes: a data processing unit (2) for setting a threshold value on the basis of a measurement value of a discharge detection signal within a first prescribed cycle, and for measuring whether a signal level of the discharge detection signal exceeds the threshold value within a subsequent second prescribed cycle; a data recording unit (3) for recording single pulse waveform data of the discharge detection signal triggered by timing when the signal level exceeds the threshold value within the second prescribed cycle; and a communication unit (4) for transferring the single pulse waveform data to a data analysis unit (6).SELECTED DRAWING: Figure 2

Description

  The present invention relates to a discharge monitoring apparatus and a discharge monitoring method capable of monitoring, for example, partial discharge of a power receiving / distributing device.

  Power receiving and distribution equipment such as transformers, switches, and rotating machines that constitute electric power facilities deteriorates in insulation performance of components due to aging, and eventually leads to equipment failure due to dielectric breakdown.

  In order to avoid this equipment failure, it is necessary to catch a sign of dielectric breakdown and repair the equipment or update the equipment before the equipment failure.

  The following Patent Document 1 discloses an invention relating to a partial discharge monitoring device and a partial discharge monitoring method. According to Patent Literature 1, it is possible to distinguish and determine a partial discharge inside a power device from an air discharge generated outside the power device (see paragraph [0010] and the like of Patent Literature 1).

  Patent Document 2 below discloses an invention relating to a partial discharge detection method and a partial discharge detection device capable of detecting partial discharge in a high-voltage power transmission and distribution facility. According to Patent Document 2, partial discharge can be constantly monitored by taking the difference between the first signal and the second signal and removing noise (paragraph [0016] of Patent Document 2). Etc.).

JP 2010-204019 A JP 2005-338016 A

  By the way, in order to continuously monitor the insulation state of the electrical equipment for a long time, it is required to continuously acquire the data amount used for monitoring the partial discharge. That is, when all waveform data of the partial discharge signal is measured and recorded, the amount of data is too large, and it is necessary to provide a separate large capacity memory in the partial discharge monitoring device, and the communication amount is enormous. Therefore, it is necessary to reduce the amount of data to be acquired compared to the conventional method for continuous long-term monitoring of partial discharge even in consideration of future increase in communication speed and increase in memory capacity. .

  However, the invention described in each of the above-mentioned patent documents relates to a technique for performing discharge mode determination and noise discrimination, and does not particularly refer to the amount of data used for monitoring partial discharge of power receiving / distributing equipment.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a discharge monitoring device capable of reducing the amount of data used for discharge monitoring and capable of monitoring discharge for a long time, and discharge monitoring. It is to provide a method.

  The present invention is a discharge monitoring device for monitoring the discharge of the power distribution equipment, set a threshold based on a measured value within a first predetermined period of the discharge detection signal emitted from the power distribution equipment, Triggered by a data processing unit that measures whether or not the signal level of the discharge detection signal exceeds the threshold within a second predetermined period, and a timing that exceeds the threshold within the second predetermined period A data recording unit that records single pulse waveform data of the discharge detection signal, and a communication unit that transfers the single pulse waveform data to a data analysis unit.

  Moreover, the discharge monitoring apparatus in this invention WHEREIN: The said threshold value can be made into the maximum value in the 1st predetermined period of the said discharge detection signal.

  In the discharge monitoring apparatus according to the present invention, the threshold value may be a value obtained by multiplying a maximum value within a first predetermined period of the discharge detection signal by a coefficient.

  Further, in the discharge monitoring apparatus according to the present invention, the threshold value may be an Nth largest value within a first predetermined period of the discharge detection signal.

  In the discharge monitoring apparatus according to the present invention, it is preferable that the threshold is set within a specific phase range within a first predetermined period of the discharge detection signal.

  Further, in the discharge monitoring apparatus according to the present invention, the discharge detection signal acquired within the first predetermined period is divided into signal levels, the number of data having a peak value at each signal level is measured, and the largest Preferably, a signal level range for threshold setting is determined based on the number of data from the signal level, and the threshold is set within the signal level range.

  In the discharge monitoring apparatus according to the present invention, the threshold value may be set in the signal level range equal to or less than the Nth minimum value as viewed from the largest signal level, with a predetermined number of data or less as a minimum value. preferable.

  In the discharge monitoring apparatus according to the present invention, it is preferable that the minimum value has 0 data.

  In the discharge monitoring apparatus according to the present invention, the data processing unit measures a peak value of the discharge detection signal every unit time obtained by dividing the first predetermined period into a plurality of times, and the data recording unit Record peak data combining values, and record the single pulse waveform data using the threshold value set based on the peak value, and the communication unit transfers the peak data together with the single pulse waveform data. It is preferable to do.

  Further, in the discharge monitoring apparatus according to the present invention, the data processing unit includes a plurality of peak measuring units having different peak value acquisition timings, and the data recording unit stores each peak value measured by each peak measuring unit. It is preferable to combine and record the peak data.

  In the discharge monitoring apparatus according to the present invention, it is preferable that the data processing unit generates a measurement timing signal based on power supply phase information and measures the peak value based on the measurement timing signal.

  Moreover, the discharge monitoring apparatus in this invention can be set as the structure further equipped with the said data analysis part which performs a discharge analysis based on the transfer data from the said communication part.

  Moreover, the discharge monitoring apparatus in this invention can be set as the structure further equipped with the sensor part which acquires the discharge detection signal discharge | released from the said power distribution apparatus.

  Further, in the discharge monitoring apparatus according to the present invention, the sensor unit can be used to determine whether or not discharge has occurred. The ambient environment information of the power receiving / distributing device, the operation status information of the power receiving / distributing device, or the surroundings Environmental information and the driving situation information can be acquired.

  In the discharge monitoring apparatus according to the present invention, it is preferable that the data recording unit records the single pulse waveform data by going back a recording time by a fixed time from the trigger timing.

  Moreover, in the discharge monitoring apparatus according to the present invention, it is preferable that the data processing unit updates the threshold value measurement every first predetermined period.

  In the discharge monitoring apparatus according to the present invention, the data processing unit can sample the discharge detection signal at a sampling frequency of 1 GHz or more.

  The present invention is also a discharge monitoring method for monitoring discharge of a power receiving / distributing device, wherein a threshold value is set based on a measured value within a first predetermined period of a discharge detection signal emitted from the power receiving / distributing device. A step of setting, a step of measuring whether or not the signal level of the discharge detection signal exceeds the threshold within a second predetermined period, and a timing when the threshold exceeds the threshold within the second predetermined period as a trigger. And recording the single pulse waveform data of the discharge detection signal, and transferring the single pulse waveform data to a data analyzer.

  According to the discharge monitoring apparatus and the discharge monitoring method of the present invention, it is possible to reduce the amount of data used for discharge monitoring and to monitor discharge for a long time.

It is a conceptual diagram which shows the typical q-phi characteristic of a partial discharge pattern and a noise pattern. It is a block diagram which shows the structure of the discharge monitoring apparatus in the 1st Embodiment of this invention. It is a time chart for demonstrating the discharge monitoring method using the discharge monitoring apparatus of 1st Embodiment, and is a figure for demonstrating mainly the production | generation of a threshold value and a trigger signal. It is a time chart figure for acquiring single shot waveform data. It is a figure which shows the typical single-shot pulse waveform of a partial discharge pattern and a noise pattern. It is a time chart figure of a power supply voltage waveform and a partial discharge detection signal for explaining a threshold setting method different from FIG. It is a time chart figure of a power supply voltage waveform and a partial discharge detection signal for explaining a problem at the time of setting a threshold in the state where a partial discharge detection signal and noise shown in FIG. 3 are mixed. It is the figure which divided the time chart figure of a power supply voltage waveform and a partial discharge detection signal into the phase range used as the object of threshold setting, and the phase range outside a target. 4 is a graph showing a relationship between a signal level and the number of data for explaining a threshold setting method different from FIG. 3. It is a block diagram which shows the structure of the discharge monitoring apparatus in the 2nd Embodiment of this invention. It is a time chart figure until it acquires q-phi characteristic data of a detection signal concerning partial discharge using a discharge monitoring device of a 2nd embodiment. It is a time chart for demonstrating the discharge monitoring method using the discharge monitoring apparatus of 2nd Embodiment, and is a figure for demonstrating mainly the production | generation of a threshold value and a trigger signal. It is a time chart figure of data transfer in this embodiment.

  Hereinafter, an embodiment of the present invention (hereinafter abbreviated as “embodiment”) will be described in detail. In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the meaning.

  FIG. 1A shows typical q-φ characteristics of a partial discharge pattern obtained as a partial discharge detection signal when a partial discharge detection sensor is attached to a high-voltage power receiving / distribution device such as an insulation insulator and a partial discharge is detected. On the other hand, FIG. 1B shows a noise pattern.

  Here, the “q-φ characteristic” is the relationship between the phase of the power supply voltage waveform when a high voltage is applied to the high-voltage power distribution device and the partial discharge level (discharge charge amount) obtained from the partial discharge detection sensor. It refers to a certain discharge charge-voltage phase characteristic.

  As is apparent from FIG. 1A, the partial discharge occurs when the potential difference of the power supply voltage applied to the high-voltage power receiving / distributing device is large. As shown in FIG. 1A, the sensor detection signal as the partial discharge pattern has a high signal intensity in the vicinity of 90 deg and 270 deg. On the other hand, as shown in FIG. 1B, the sensor detection signal as a noise pattern often has q-φ characteristics that are not related to the phase of the power supply voltage waveform. As described above, there is a difference in waveform pattern between partial discharge and noise. However, if the sensor detection signal from the partial discharge detection sensor is directly used for partial discharge analysis, there is a problem that the amount of data becomes large.

That is, when obtaining the q-φ characteristic of the partial discharge detection signal obtained from the partial discharge detection sensor, it is necessary to continuously acquire the data of the partial discharge detection signal for at least one cycle. For example, when acquiring the waveform data of the partial discharge detection signal as an example, assuming that the sampling frequency is 1 GHz and the frequency of the power supply voltage waveform is 50 Hz, 20 MByte (= 1 × 10 ⁹ × ( 1/50)). If this 8-bit data for one cycle is transferred to an external data server via a wireless LAN with a communication speed of 256 Kbps, it takes 625 sec (= 20 × 10 ⁶ × 8 ÷ (256 × 10 ³ )).

  As described above, the memory for temporarily recording the q-φ characteristics of the partial discharge detection signal requires at least 20 Mbytes, and the data transfer time becomes long. Therefore, the partial discharge is continuously monitored for a long time. Therefore, it is necessary to reduce the amount of data used for monitoring the partial discharge.

  Therefore, the present inventors have reached the present invention for the purpose of establishing a discharge monitoring device and a discharge monitoring method capable of continuously monitoring partial discharge by reducing the amount of data used for monitoring partial discharge. That is, the gist of the present invention is to obtain single pulse waveform data from the partial discharge detection signal, and use this single pulse waveform data for partial discharge monitoring, thereby reducing the amount of data and enabling continuous monitoring for a long time. It is to do.

(First embodiment)
FIG. 2 is a block diagram showing the configuration of the discharge monitoring apparatus according to the first embodiment of the present invention. As shown in FIG. 2, the discharge monitoring apparatus 1 according to the present embodiment includes a data processing unit 2, a data recording unit 3, a communication unit 4, a sensor unit 5, and a data analysis unit 6.

  The data processing unit 2 includes a data sampling unit 21, a threshold measurement unit 22, a trigger timing measurement unit 23, and a measurement timing signal processing unit 24.

  The partial discharge detection signal detected by the partial discharge detection sensor 51 is sampled at a high frequency by the data sampling unit 21. In the present embodiment, it is preferable that the sampling frequency is 1 GHz or more. In particular, when a high-frequency current sensor is used as the partial discharge detection sensor 51, the current accompanying the discharge is about 100 kHz to 500 MHz. Therefore, if the sampling frequency is 1 GHz or more, the sampling frequency is about twice or more the frequency characteristic. It can be. Thereby, sampling can be performed at a frequency higher than twice the bandwidth of the frequency component of the waveform of the partial discharge detection signal. For this reason, the measurement of the threshold value mentioned later, the measurement of q-phi characteristic data (2nd Embodiment), and the measurement of the single pulse waveform data of a partial discharge detection signal can be performed accurately.

  The data-sampled partial discharge detection signal is sent to the threshold measurement unit 22 and the trigger timing measurement unit 23. In the following description, unless otherwise specified, the partial discharge detection signal handled by the data processing unit 2 is described as being data-sampled.

  The threshold measurement unit 22 measures the maximum value (threshold) of the partial discharge detection signal within the period T.

  The trigger timing measurement unit 23 measures whether or not the signal level of the partial discharge detection signal exceeds a threshold value. When the threshold is exceeded, single pulse waveform data of the partial discharge detection signal is measured with the timing as a trigger.

  The measurement timing signal processing unit 24 generates a measurement timing signal based on the power supply phase information of the high-voltage AC power supply 72 attached to the high voltage power distribution device 71. Then, the measurement timing signal is transmitted to the threshold measurement unit 22 and the trigger timing measurement unit 23.

  The data recording unit 3 includes a threshold recording unit 31 and a single pulse waveform data recording unit 32. The threshold recording unit 31 records the threshold measured by the threshold measurement unit 22.

  The single pulse waveform data recording unit 32 records single pulse waveform data of the partial discharge detection signal. Here, the “partial discharge detection signal” refers to a signal monitored by the discharge monitoring device 1 in order to detect partial discharge, and includes switching noise and external noise in addition to the signal generated at the time of discharge. Thus, the “partial discharge detection signal” is a composite of pulse signals resulting from various phenomena. The “single pulse waveform” is a waveform extracted in a short time in order to detect only a pulse signal resulting from an independent single phenomenon. In other words, “single pulse waveform” refers to signal data obtained by extracting only one pulse signal from the entire signal data.

  The communication unit 4 includes a communication device 42 for transferring the single pulse waveform data recorded by the single pulse waveform data recording unit 32 to the data analysis unit 6. In the communication unit 4, data such as a threshold value recorded in the threshold value recording unit 31 can be transferred to the data server 61.

  The sensor unit 5 includes at least a partial discharge detection sensor 51. For the detection of partial discharge, sensors for current, electromagnetic waves, ultrasonic waves, light, and the like associated with the discharge phenomenon are used. Here, in the case of the optical method, the discharge inside the insulator cannot be detected, and in the case of the ultrasonic method, since it is vulnerable to noise, as the partial discharge detection sensor 51, a high-frequency current sensor as a current method or an electromagnetic method is used. An electromagnetic wave antenna or the like is preferable. The rough frequency band of the detection signal obtained from the partial discharge detection sensor 51 is such that the current accompanying discharge is about 100 kHz to 500 MHz, and the electromagnetic wave accompanying discharge is about 100 MHz to 1 GHz. Although it is difficult to separate the disturbance noise and the partial discharge signal due to the factory environment or the like only with such frequency characteristics, according to the present embodiment, noise discrimination can be appropriately performed.

  In the present embodiment, the sensor unit 5 preferably includes a humidity sensor 52, an ammeter 53, and the like. The humidity sensor 52 can acquire humidity information as ambient environment information. For example, the humidity information is sent to the data recording unit 3 and transferred from the communication unit 4 to the data analysis unit 6. Or it is good also as a communication system which can transfer humidity information directly to the data analysis part 6 as another form.

  Moreover, in this Embodiment, it is possible to acquire the electric current value in the case of the partial discharge measurement measured with the ammeter 53 as the operating condition information of the high voltage power distribution device 71. This current value information is recorded by the data recording unit 3 and transferred from the communication unit 4 to the data analysis unit 6. Or as another form, it is good also as a communication system which can transfer electric current value information to the data analysis part 6 directly.

  The data analysis unit 6 includes a data server 61, for example. Single pulse waveform data is transferred from the communication unit 4 to the data server 61. Based on the transferred information, the data server 61 can analyze the presence / absence of partial discharge, noise classification, partial discharge type, and the like. For example, the data server 61 stores typical waveform data of partial discharge patterns and noise patterns. As an example, FIG. 5A is a single pulse waveform of a partial discharge pattern, and FIG. 5B is a single pulse waveform of a noise pattern.

  As shown in FIG. 5A, the single pulse waveform of the partial discharge pattern shows a waveform that has the largest amplitude immediately after the occurrence and then gradually attenuates. On the other hand, as shown in FIG. 5B, the single-shot pulse waveform of the noise pattern shows a waveform in which the amplitude gradually increases and the amplitude attenuates over time. Thus, the waveform shape of the single pulse waveform is different between the partial discharge pattern and the noise pattern, and the data server 61 stores such a characteristic waveform difference. Then, by comparing the waveform data transferred to the data server 61 with various data stored in the database and analyzing it, it is possible to determine partial discharge and noise, or to determine the type of partial discharge. .

  Next, the discharge monitoring method of the first embodiment using the discharge monitoring device 1 of FIG. 2 will be described.

  In the discharge monitoring method according to the first embodiment, (A) a step of setting a threshold based on a measured value within a first predetermined period of a partial discharge detection signal emitted from the high-voltage power distribution device 71, (B ) A step of measuring whether or not the signal level of the partial discharge detection signal exceeds a threshold value within the second predetermined period, and (C) a timing at which the threshold value exceeds the threshold value within the second predetermined period as a trigger. A step of recording single pulse waveform data of the discharge detection signal, and a step (D) of transferring the single pulse waveform data to the data analysis unit 6.

  The discharge monitoring method of the first embodiment will be specifically described with reference to the time charts of FIGS. 3A shows a power supply voltage waveform with respect to time, FIG. 3B shows a partial discharge detection signal with respect to time, FIG. 3C shows a time chart of a threshold value, FIG. 3D shows a time chart of a waveform data measurement signal, FIG. 3E shows the trigger signal generation timing.

  As shown in the position of FIG. 3E, the cycle time T of the power supply phase (phase of the power supply voltage waveform) from the start of measurement is set as the threshold measurement time. This cycle time T is obtained by converting the “first predetermined cycle” shown in (A) above into time. This cycle time T indicates the time required for one cycle of the power supply voltage waveform (partial discharge detection signal). Note that it is possible to arbitrarily determine how many cycles the threshold measurement time is.

  The threshold measurement unit 22 measures, for example, the value at which the signal level of the partial discharge detection signal shown in FIG. 3B is the maximum in the period time T as a threshold (step (A) above). The threshold value is not particularly limited as long as it is a setting method that can be set based on the measurement value within the first predetermined period (within the period time T). This will be described as the maximum value of the signal. Other threshold setting methods will be described later.

  At the time of this threshold measurement, the measurement timing signal processing unit 24 detects, based on the power supply phase information, the power supply phase 0 deg at which the threshold measurement is started at the timing when the power supply voltage waveform changes from negative to positive, and this information is detected by the threshold measurement unit. 22 to send. Thereby, the cycle time T, which is the threshold measurement time, can be set according to the power supply phase accurately. Then, as shown in FIG. 3C, peak hold is performed using the maximum signal level as a threshold value. This threshold value is recorded in the threshold value recording unit 31. The threshold shown in FIG. 3C is sent from the threshold recording unit 31 to the trigger timing measurement unit 23.

  As shown in the position of FIG. 3E, the trigger waiting time Tr for trigger timing measurement is set continuously to the cycle time T which is the threshold measurement time. The trigger waiting time Tr is obtained by converting the “second predetermined period” shown in (B) above into time. In this embodiment, the trigger waiting time Tr is the time required for one cycle of the power supply voltage waveform (partial discharge detection signal). However, how many cycles the trigger waiting time Tr is used can be arbitrarily determined. it can.

  A measurement timing signal is transmitted from the measurement timing signal processing unit 24 to the trigger timing measurement unit 23, and a trigger waiting time Tr is started. Then, it is measured whether or not the signal level of the partial discharge detection signal shown in FIG. 3B exceeds the threshold within the trigger waiting time Tr (step (B) above). This measurement is performed by the trigger timing measurement unit 23.

  As shown in FIG. 3E, the trigger signal is generated at the moment when the signal level exceeding the threshold is obtained within the trigger waiting time Tr.

  In the present embodiment, single pulse waveform data of a partial discharge detection signal is acquired with a timing at which a signal level exceeding a threshold is obtained as a trigger. A time chart for the acquisition will be described with reference to FIG.

  4A shows a time chart of the single pulse waveform data of the partial discharge detection signal, FIG. 4B shows the generation timing of the trigger signal, FIG. 4C shows the recording range of the single pulse waveform data as time, and FIG. The time chart regarding the recording of single shot waveform data is shown.

  In the present embodiment, the single pulse waveform data of the partial discharge detection signal is recorded with the detection of a detection signal having a signal level exceeding the threshold within the trigger waiting time Tr (step (C)). As shown in FIG. 4B, when the trigger signal is generated, as shown in FIG. 4C, the recording time is traced back by a certain time (corresponding to the pre-measurement time T0) from the timing at which the trigger signal is measured, and the full length measurement time. Define Tm.

  Then, single pulse waveform data is recorded within the full length measurement time Tm (FIG. 4D).

  In this embodiment, for example, in the measurement period in which the waveform data measurement signal shown in FIG. 3D is generated, the single pulse waveform data recording unit 32 always acquires and overwrites the single pulse waveform data at a predetermined short interval. And save the latest. That is, the single waveform data shown in FIG. 4A is continuously updated, the acquisition of the single pulse waveform data at the timing when the trigger signal of FIG. 4B is generated, and the waveform data measurement period ends. Here, the single pulse waveform data required in the present embodiment is single pulse waveform data acquired at the trigger timing. This single waveform data has a signal level exceeding a threshold value and may be a signal resulting from partial discharge. Therefore, the single waveform data at the timing when the trigger signal is generated is recorded in the single pulse waveform data recording unit 32 as the latest one and transferred to the data server 61 via the communication device 42 (step (D) above) ).

  When the single waveform data at the timing when the trigger signal is generated is set to be acquired n times (n is a plurality), the waveform data measurement period shown in FIG. End when n times.

  When the single pulse waveform data is transferred to the data server 61, it is checked which waveform the transferred single pulse waveform data matches or which waveform is closest to the database. . Then, it can be determined whether the transferred single pulse waveform data is based on partial discharge or noise. That is, as shown in FIG. 5, the single-shot waveform data differs between the partial discharge pattern and the noise pattern. Therefore, if the single waveform data transferred to the data server 61 matches or is close to that shown in FIG. 5B, it can be determined as noise. On the other hand, if it coincides with or is close to that shown in FIG.

  Hereinafter, threshold setting in the present embodiment will be described in detail.

<Threshold setting method (1)>
In FIG. 3, the threshold value is set as the maximum value within the first predetermined period (period time T) of the partial discharge detection signal. Thereby, it is possible to appropriately detect the maximum level of partial discharge with the greatest damage to the target device.

  However, if the threshold is set to the maximum value of the partial discharge detection signal, the partial discharge cannot be detected properly if the partial discharge does not reach the maximum level in the second predetermined period. Therefore, it is possible to set a threshold as follows.

<Threshold setting method (2)>
A value obtained by multiplying the maximum value of the partial discharge detection signal (absolute value) shown in FIG. 6 by a coefficient can be used as the threshold value. The coefficient value can be arbitrarily set within a range larger than 0 and smaller than 1.

  When the coefficient value is increased, it approaches the maximum value, and therefore, there is a high possibility that the partial discharge cannot be detected appropriately. On the other hand, if the coefficient value is set low, the number of detected data increases too much. Therefore, the coefficient is adjusted so that the desired number of data can be acquired. The adjustment of the coefficients can be performed manually by the user, but can also be performed automatically. As an initial setting, it is desirable that the coefficient be about 0.80 to 0.95.

  As described above, in the method of setting the threshold value by multiplying the coefficient by the maximum value, partial discharge can be detected even when the partial discharge signal level fluctuates within the second predetermined period after the threshold value is set. Thus, it is possible to prevent the non-detection of the single pulse waveform.

<Threshold setting method (3)>
The Nth numerical value counted from the larger partial discharge detection signal (absolute value) shown in FIG. 6 is set as the threshold value. FIG. 6 shows the second to fifth. The fifth is a negative value, but is the fifth largest value in terms of absolute value. As the N value is increased, the number of detected data increases, so the N value is adjusted so that the desired number of data can be acquired.

  For example, as an initial setting, the N value is set to 1. That is, at first, the maximum value of the partial discharge detection signal is set as the threshold as in the above <Threshold setting method (1)>. Then, the N value can be adjusted to a numerical value of N = 2 or more automatically or arbitrarily by the user from the partial discharge detection state within the second predetermined period after the threshold value is set.

  As described above, in the method of setting the Nth largest value as the threshold value, the number of acquired single pulse waveforms can be appropriately controlled.

  Also, the N value can be set as a “group”. That is to say, those having approximately the same peak value are regarded as being in the same group and summarized. Thereby, the threshold value can be stably set in consideration of variations in partial discharge and measurement errors. For example, it is assumed that a plurality of peak values are obtained around 20 as data values, and a plurality of peak values are obtained around 19 as data values. At this time, a plurality of peak values around 20 are regarded as the same “group”, and a plurality of peak values around 19 are regarded as the same “group”. Then, the Nth numerical value counted from the large value of the group is set as the threshold value. The range constituting the group can be arbitrarily adjusted so that a desired number of data can be acquired.

  By the way, as shown in FIG. 7, when noise is present in the partial discharge detection signal, the threshold value setting method may cause the threshold value to be set at the noise signal level. As shown in FIG. 7, the first to fifth numerical values are noise. Therefore, not only the setting method using the maximum value of <threshold setting method (1)> as a threshold value, but also the <threshold setting method (2)> and <threshold setting method (3)>, Depending on the N value, noise may be set as a threshold value.

  Therefore, it is preferable that noise is not included in the threshold setting target as follows.

<Threshold setting method (4)>
It is known from past literatures and empirical rules that noise is likely to occur at a phase of 0 deg and 180 deg. For this reason, when setting each threshold value from the above <threshold value setting method (1)> to <threshold value setting method (3)>, in order to exclude noise from the threshold setting target, the threshold value is set within the first predetermined period. It is preferable to set within a specific phase range excluding 0 deg and 180 deg.

  In addition, the partial discharge signal is characterized by being easily generated at a specific phase. If the partial discharge phenomenon progresses, the partial discharge occurs even outside the specific phase. However, the partial discharge at a specific phase does not disappear. From the past literature data and the like, the phases where partial discharge occurs are in the vicinity of phases 15 deg to 90 deg and 195 deg to 270 deg. In this phase range, noise tends to be out of the threshold setting target. Therefore, more preferably, as shown in FIG. 8, the threshold value is set based on the measured values of the partial discharge detection signal within a specific phase range of 15 deg to 90 deg and 195 deg to 270 deg.

  As shown in FIG. 8, noise deviates from the specific phase range. That is, when the specific phase range is not defined, the noise shows the maximum value, and in each threshold setting from the above <threshold setting method (1)> to <threshold setting method (3)>, the threshold is set by noise. There is a risk.

  On the other hand, as shown in FIG. 8, noise can be excluded from the threshold setting target by defining a specific phase range. Therefore, each threshold setting from the above <threshold setting method (1)> to <threshold setting method (3)> can be performed on the partial discharge detection signal excluding noise in the specific phase range. As shown in FIG. 8, the partial discharge detection signals can be ordered in magnitude within a specific phase range.

  As a result, it is possible to detect a single waveform data signal using a partial discharge signal buried in noise. Further, in the single-shot pulse waveform data, information on the phase generated from the power supply voltage value can also be discriminated, so that the partial discharge signal and the noise signal can be discriminated from this phase information.

<Threshold setting method (5)>
The partial discharge detection signal obtained in FIG. 7 is divided into a plurality of signal levels as shown in FIG. The signal level has a predetermined range. The degree of the range can be arbitrarily set. Then, as shown in FIG. 9, the number of data having a peak value at each signal level is measured.

  In FIG. 9, the signal level is higher on the right side of the horizontal axis. As shown in FIG. 9, it can be seen that the number of data is roughly three peaks. These peaks are designated as “group 1”, “group 2”, and “group 3” in descending order of signal level. As shown in FIG. 9, there is a minimum value in which the number of data falls between the groups. In this embodiment, the minimum value also exists in “group 1”. “Minimum value” refers to a predetermined number of data or less.

  Here, in this embodiment, the number of data is set to “minimum value” of 0. In the present embodiment, the Nth “minimum value” is measured when viewed from “group 1” having a high signal level. At this time, “minimum value (0)” at a signal level higher than “group 1” can be excluded from the measurement target. As shown in FIG. 9, the first “minimum value (1)” is located in “group 1”, and the second “minimum value (2)” is divided into “group 1” and “group 2”. ”Between. As shown in FIG. 9, “minimum value (2)” is arranged in a row of three, and in such a case, these may be combined into “minimum value (2)”. It is also possible to count separately from “minimum value (2)”, “minimum value (3)”, and “minimum value (4)”. Here, three consecutive minimum values are referred to as “minimum value (2)”.

  In the present embodiment, the threshold value can be set in a signal level range equal to or smaller than the Nth minimum value. That is, “Group 1” shown in FIG. 9 is the first to fifth peak values shown in FIG. 7 and corresponds to noise. Therefore, by setting the N value to 2 and setting the threshold value within the signal level range equal to or smaller than the second minimum value, noise can be excluded from the threshold setting target.

  After the data is arranged in this way, the threshold setting method can be performed using <Threshold Setting Method (1)> to <Threshold Setting Method (3)>.

  As described above, by using <Threshold setting method (5)>, noise can be excluded from threshold setting targets, and therefore, it is possible to detect a single waveform data signal using a partial discharge signal buried in noise.

  In the present embodiment, the minimum value is set when the number of data is 0. However, the minimum value may be set when the number is less than a preset numerical value of 1 or more, and the minimum is set under the condition that 0 continues for a certain interval or more. It may be a value. Further, in the present embodiment, it is only necessary to determine the signal level range used for threshold setting based on the number of data from the largest signal level. For example, as shown in FIG. 9, the distribution of the number of data is divided into groups, but the threshold may be set in a signal level range equal to or lower than the Nth group.

<Threshold setting method (6)>
In this embodiment, the above threshold setting method can be used alone, or a plurality of threshold setting methods can be used.

  For example, as an initial setting, the maximum value is set as the threshold value using <Threshold setting method (1)>. At this time, <threshold setting method (1)> and <threshold setting method (4)> or <threshold setting method (5)> can be used simultaneously so that noise can be excluded from the threshold setting target. It is preferable to keep it.

  However, for example, in the case where the partial discharge detection signal suddenly increases within the first predetermined period, when the threshold is set with the signal as the maximum value, within the second predetermined period after the threshold is set, Appropriately, the partial discharge cannot be detected, and the single pulse waveform tends to be undetected. Therefore, when it is determined that the threshold value is not properly set, such as when the single pulse waveform has not been detected for a predetermined period of time, the threshold value setting method (2 )> And <Threshold setting method (3)>. For example, three methods of <threshold setting method (1)>, <threshold setting method (2)>, and <threshold setting method (3)> may be switched in order. Alternatively, any one of <Threshold setting method (2)> and <Threshold setting method (3)> may be used in addition to <Threshold setting method (1)>. Further, as the initial setting, <threshold setting method (2)> or <threshold setting method (3)> can be used instead of <threshold setting method (1)>.

(Second Embodiment)
Next, the configuration of the discharge monitoring device and the discharge monitoring method according to the second embodiment of the present invention will be described with reference to FIGS. In addition, the same component (functional part) as FIG. 2 was attached | subjected the same code | symbol as FIG. Refer to FIG. 2 for a detailed description of components having the same reference numerals as those in FIG. Also in the discharge monitoring method of the second embodiment, there is no change in having the steps (A) to (D) as in the first embodiment. In the following, a description will be given focusing on differences from the first embodiment shown in FIG.

  In the second embodiment, the data processing unit 2 includes a first peak measurement unit 25 and a second peak measurement unit 26. The first peak measurement unit 25 and the second peak measurement unit 26 are connected to the q-φ characteristic data recording unit 33 of the data recording unit 3.

  In the second embodiment, in the first peak measurement unit 25 and the second peak measurement unit 26 of the data processing unit 2, the partial discharge detection signal is generated for each unit time obtained by dividing the first predetermined period into a plurality of times. Measure the peak value. Further, the q-φ characteristic recording unit 33 of the data recording unit 3 records peak data obtained by combining the peak values obtained from the peak measuring units 25 and 26 as q-φ characteristic data. Thus, the second embodiment differs from the first embodiment in that q-φ characteristic data obtained by performing predetermined data processing on the partial discharge detection signal is measured and recorded.

  The acquisition of q-φ characteristic data will be described below with reference to the time chart of FIG. 11A shows a power supply voltage waveform with respect to time, FIG. 11B shows a time chart of a partial discharge detection signal, and FIG. 11C shows a time chart of a first measurement timing signal transmitted to the first peak measurement unit 25. Indicates. Further, FIG. 11D shows a time chart of the second measurement timing signal transmitted to the second peak measurement unit 26, and FIG. 11E shows the first peak value measured by the first peak measurement unit 25. 11F shows a time chart of the second peak value measured by the second peak measuring unit 26, and FIG. 11G shows each first peak value of FIG. 11E and each of FIG. 11F. The peak data formed by combining the second peak value is shown.

  As shown in the position of FIG. 11G, the peak value measurement period is the period time T (first predetermined period) of the power supply phase (the phase of the power supply voltage waveform), and the period time T is divided by the unit time t. . As described above, the measurement start timing is the power supply phase 0 deg at which the power supply voltage waveform detected by the measurement timing signal processing unit 24 based on the power supply phase information changes from negative to positive. The measurement timing signal processing unit 24 divides the period time T described above into unit times t according to the measurement start timing. And the 1st measurement timing signal (Drawing 11C) transmitted to the 1st peak measurement part 25 and the 2nd measurement timing signal (Drawing 11D) transmitted to the 2nd peak measurement part 26 are generated. As shown in FIGS. 11C and 11D, the first measurement timing signal and the second measurement timing signal are generated so as to occur alternately in unit time t.

  The first peak measurement unit 25 measures the peak value of the partial discharge detection signal shown in FIG. 11B for each unit time t of the first measurement timing signal, and obtains the plurality of first peak values shown in FIG. 11E. obtain.

  Further, the second peak measurement unit 26 measures the peak value of the partial discharge detection signal shown in FIG. 11B for each unit time t of the second measurement timing signal, and a plurality of second peaks shown in FIG. 11F. Get the value.

  Thus, the first peak measurement unit 25 and the second peak measurement unit 26 alternately measure the peak value of the partial discharge detection signal every unit time.

  The peak data shown in FIG. 11G obtained by combining the first peak value information shown in FIG. 11E and the second peak value information shown in FIG. 11F is obtained by the q-φ characteristic data recording unit 33. Recorded as data.

  Subsequently, for example, using the maximum peak value of the q-φ characteristic data as a threshold value, it is measured whether or not the signal level of the partial discharge detection signal exceeds the threshold value within the trigger waiting time Tr (second predetermined period). Here, the maximum peak value is set as the threshold value. In the threshold value setting in the second embodiment, the above-described <Threshold value setting method (1)> to <Threshold value setting method (6)> are appropriately set. Can be used.

  12A shows a power supply voltage waveform with respect to time, FIG. 12B shows a partial discharge detection signal with respect to time, FIG. 12C shows q-φ characteristic data obtained at a cycle time T, and FIG. 12D shows waveform data. A time chart of the measurement signal is shown, and FIG. 12E shows the generation timing of the trigger signal.

  In the second embodiment, the peak maximum value is calculated from the q-φ characteristic data shown in FIG. 12C measured at the cycle time T. For example, the peak value is peak-held as the threshold value and recorded in the threshold value recording unit 31. To do.

  As shown in the position of FIG. 12E, the trigger waiting time Tr is determined continuously with the period time T. Note that it is possible to arbitrarily determine how many cycles the trigger waiting time Tr is to be set.

  A measurement timing signal accompanying the start of the trigger waiting time Tr is transmitted from the measurement timing signal processing unit 24 to the trigger timing measurement unit 23. Thereby, measurement of trigger timing is started. That is, the trigger timing measurement unit 23 measures whether or not the signal level of the partial discharge detection signal exceeds a threshold value. In addition, as shown to FIG. 12D, a waveform data measurement signal rises with the start of trigger waiting time Tr.

  When a signal level exceeding the threshold is obtained within the trigger waiting time Tr, a trigger signal is generated as shown in FIG. 12E and the waveform data measurement signal is terminated.

  Here, as shown in FIG. 12D, during the period in which the waveform data measurement signal is valid, single pulse waveform data is acquired in real time according to the signal level of the partial discharge detection signal. Next, when the single pulse waveform data is acquired, the previous single pulse waveform data is overwritten and stored. Therefore, the single pulse waveform data recording unit 32 is always in a state where the latest single pulse waveform data is stored.

  As shown in FIG. 12E, the single pulse waveform data is overwritten and stored in the single pulse waveform data recording unit 32 at the moment when the trigger signal rises, and the waveform data measurement signal is terminated. At this time, the single pulse waveform data to be stored is, as described with reference to FIGS. 4C and 4D, the full length measurement time Tm that goes back the storage time by a fixed time (corresponding to the lowest pre-measurement time T0) from the trigger timing. Minutes are recorded.

  Then, q-φ characteristic data and single pulse wavelength data are transferred from the q-φ characteristic data recording unit 33 and the single pulse waveform data recording unit 32 to the data analysis unit 6 via the communication devices 41 and 42. . The data analysis unit 6 can determine whether the transferred single pulse waveform data is based on partial discharge or noise based on a database. At this time, the q-φ characteristic data is used to characterize the type of partial discharge and accurately perform noise discrimination.

  FIG. 13 is a flowchart showing a data recording / transfer method. 13A shows the power supply voltage waveform with respect to time, FIG. 13B shows the recording timing of q-φ characteristic data, FIG. 13C shows the transfer timing of q-φ characteristic data, and FIG. 13D shows the recording timing of single-shot pulse waveform data. FIG. 13E shows the transfer timing of single-shot pulse waveform data.

  As shown in FIG. 13B, the q-φ characteristic data is recorded, and at the recording end timing, the q-φ characteristic data is transferred as shown in FIG. 13C. In addition, the trigger waiting time Tr is started at the end timing of the recording of the q-φ characteristic data (shown at the position in FIG. 13E). Using the trigger signal measured within the trigger waiting time Tr as recording timing, single pulse waveform data is recorded as shown in FIG. 13D. When the single pulse waveform data is recorded, the single pulse waveform data is transferred as shown in FIG. 13E. At this time, the transfer of the single pulse waveform data and the recording timing of the q-φ characteristic data may overlap, but the data transfer and the recording can be performed at the same time, and no problem occurs.

  Further, when the transfer timings of the q-φ characteristic data and the single pulse waveform data overlap, it is preferable to start the other data transfer after ending the data transfer that started the transfer first.

  In FIG. 13, q-φ characteristic data is recorded and transferred at a predetermined cycle interval. As a result, the latest q-φ characteristic data is always accumulated in the data analysis unit 6. It is possible to perform discharge monitoring more appropriately.

  In addition, it is preferable to set the total time of the cycle time T and the trigger waiting time Tr shorter than the total time of the transfer of the q-φ characteristic data and the single pulse waveform data. As a result, a blank time during which neither measurement nor transfer is performed is less likely to occur, and continuous measurement and accumulation of data can be performed.

  As described above, in the second embodiment, in the time chart of q-φ characteristic data acquisition shown in FIG. 11, the power supply voltage phase is divided into unit phases, and the peak value of the partial discharge detection signal for each unit phase. Measure. Then, the peak values of all phases are combined and reconstructed as q-φ characteristics. Therefore, for example, when the sampling frequency for the partial discharge detection signal is fixed to 1 GHz and a peak value is recorded for 360 deg for one cycle every unit phase 0.05 deg, q-φ characteristic data for one cycle is 7.2 kbytes ( = 360 ÷ 0.05).

For example, assuming that the single pulse waveform data is attenuated at 15 μsec and the waveform recording time is 20 μsec, the data amount for one shot of the single pulse waveform data is 20 kBytes (= 1 × 10 ⁹ × 20 × 10 ⁻⁶ ). Become. Therefore, the total of both data is 27.2 kbytes, and the time required to transfer this data to the data server at 256 kbps is 0.85 sec (= 27.2 × 10 ³ × 8 ÷ (256 × 10 ³ )). As described above, in this embodiment, it is sufficient that the memory for temporary storage has a minimum of 27.2 kBte, and the measurement can be performed about every one second.

  In the present embodiment, as shown in FIGS. 2 and 10, the discharge monitoring apparatus 1 includes a data processing unit 2, a data recording unit 3, and a communication unit 4. Then, in the data processing unit 2, the threshold value is measured based on the measurement value in the first predetermined period of the partial discharge detection signal, and then the signal level of the partial discharge detection signal in the second predetermined period is Measure whether the threshold is exceeded. The specific threshold setting is as shown from <Threshold Setting Method (1)> to <Threshold Setting Method (6)>. In addition, the data recording unit 3 records single pulse waveform data of the partial discharge detection signal with a timing at which the threshold value is exceeded within the second predetermined period as a trigger. Then, the communication unit 4 transfers single-shot pulse waveform data.

  According to the discharge monitoring apparatus 1 and the discharge monitoring method of the present embodiment, the amount of data used for discharge monitoring can be reduced, and partial discharge can be monitored for a long time. That is, single pulse waveform data is acquired based on data processing for the first partial discharge detection signal, and the single pulse waveform data is transferred as data used for discharge monitoring. For this reason, in this embodiment, the amount of data to be recorded and the amount of data to be transferred may be small. Therefore, it is possible to reduce the burden on the side of analyzing the transferred data, and the discharge monitoring device can monitor the discharge for a long time with a small amount of data.

  Further, as in the second embodiment, it is preferable to roughly process the partial discharge detection signal to obtain q-φ characteristic data and transfer it. That is, in the second embodiment, the peak value of the partial discharge detection signal is measured every unit time obtained by dividing the predetermined period into a plurality of times, and q-φ characteristic data (peak data) obtained by combining the peak values is recorded. . Then, the communication unit 4 transfers q-φ characteristic data together with the single pulse waveform data. According to this configuration, the q-φ characteristic data of the partial discharge detection signal can be obtained with a small data amount by the above data processing. Therefore, even if q-φ characteristic data is included together with single-shot pulse waveform data, it is possible to monitor discharge for a long time with a small amount of data. By using the q-φ characteristic data as discharge monitoring, noise can be more accurately classified, and further, the type of discharge can be specified appropriately.

  As shown in FIG. 10, the data processing unit 2 includes a plurality of peak measurement units 25 and 26 having different peak value acquisition timings, and the q-φ characteristic data recording unit 33 includes the peak measurement units 25 and 26. The peak data measured in (1) is combined and recorded as q-φ characteristic data. Thereby, q-φ characteristic data can be acquired appropriately. That is, peak data is acquired by separate peak measuring units 25 and 26 having different peak value acquisition timings. Thereby, when the peak value is acquired by one peak measuring unit, the peak value acquired by the other peak measuring unit can be used for the recording time in the q-φ characteristic data recording unit 33. As described above, the q-φ characteristic data can be obtained with high accuracy by alternately acquiring and recording the peak value using the plurality of peak measurement units 25 and 26 having different peak value acquisition timings. become.

  In the present embodiment, the measurement timing signal processing unit 24 of the data processing unit 2 generates a measurement timing signal based on the power supply phase information, and the peak measurement units 25 and 26 based on the measurement timing signal. Measure the peak value. That is, as shown in FIGS. 11C and 11D, the measurement timing signal of the unit time t is alternately transmitted to the peak measuring units 25 and 26, so that the timing deviation of the peak value acquisition hardly occurs, and the q-φ characteristic Data can be obtained with high accuracy.

  Further, the measurement timing signal processing unit 24 detects the power supply phase 0 deg at the timing when the power supply voltage waveform changes from negative to positive, and sets the cycle time T as the first predetermined cycle that becomes the measurement range of the threshold value and the peak value. It has established. For this reason, the cycle time T can be accurately adjusted to, for example, one cycle of the power supply voltage waveform. In addition, the trigger waiting time Tr continuous to the cycle time T can be accurately determined. As a result, q-φ characteristic data and single pulse waveform data can be obtained within a precisely divided time, and discharge can be continuously monitored for a long time more appropriately.

  In the present embodiment, the single pulse waveform data recording unit 32 records single pulse waveform data by going back the recording time by a fixed time from the trigger timing. That is, in the case of a single pulse waveform having a partial discharge pattern, the trigger timing hits the wave front as shown in FIG. 4D. Therefore, in order to capture the entire shape of the single pulse waveform, recording is performed from a position slightly earlier than the trigger timing, so that the entire length of the single pulse waveform data can be appropriately recorded.

  In this embodiment, the threshold value can be measured and updated every first predetermined period. For example, in FIG. 3, the threshold measurement cycle time T and the trigger waiting time Tr alternately occur at intervals of the power supply voltage phase, and the threshold measurement is performed and updated every first predetermined cycle. . That is, when the maximum value of the signal level of the partial discharge detection signal suddenly occurs like noise, the signal level is not appropriate as the threshold value of the single pulse waveform data of the partial discharge pattern. In particular, since the occurrence timing of such noise varies depending on the initial stage of the discharge monitoring device 1 and the usage environment, it is possible to appropriately perform long-term monitoring of discharge by periodically updating the threshold value. become. As shown in FIG. 3C, it can be seen that the detected signal level is larger than the signal level up to that point in the third cycle time T, and the threshold value is updated. It is also possible to update the q-φ characteristic data shown in the second embodiment. By updating the q-φ characteristic data, it is possible to always determine the type of discharge using the recent q-φ characteristic data and to perform more accurate partial discharge monitoring.

  Further, in the present embodiment, as shown in FIG. 2, it is possible to acquire humidity information by the humidity sensor 52 as ambient environment information of the high-voltage power distribution device 71, and to use this humidity information for determination of occurrence of discharge. Yes. Further, in the present embodiment, as shown in FIG. 2, it is possible to acquire current information from the ammeter 53 as the operation status information of the high-voltage power distribution device 71 and use this current information for the determination of the occurrence of discharge. Yes. Since the signal level of the partial discharge pattern changes according to the humidity change and current value, the presence or absence of partial discharge and noise can be obtained by using the ambient environment information such as humidity and the operation status information such as current value for data analysis. Therefore, it is possible to appropriately determine the separation and effectively monitor the discharge for a long time.

  In the present embodiment, it is preferable to sample the partial discharge detection signal at a sampling frequency of 1 GHz or more, but this is particularly effective when a high frequency current sensor as a current method is used as the partial discharge detection sensor 51. is there. The sampling frequency can be about twice or more the frequency characteristic of the partial discharge detection signal, and data loss during data sampling can be suppressed. As a result, it is possible to accurately measure the threshold, the q-φ characteristic data, and the single pulse waveform data of the partial discharge detection signal.

  The present invention is not limited to the above embodiment, and can be implemented with various modifications. Other modifications may be made as appropriate without departing from the scope of the object of the present invention.

  For example, in FIGS. 2 and 10, the discharge monitoring device 1 has been described including the sensor unit 5 and the data analysis unit 6. However, the discharge monitoring device 1 does not include the sensor unit 5 and the data analysis unit 6. Alternatively, only one of the sensor unit 5 and the data analysis unit 6 may be included. That is, the discharge monitoring apparatus 1 of the present embodiment only needs to include at least the data processing unit 2, the data recording unit 3, and the communication unit 4. The sensor unit 5 and the data analysis unit 6 are provided as separate devices from the discharge monitoring device 1 and are configured to be used in combination with the discharge monitoring device 1 of the present embodiment when performing discharge monitoring. it can.

  Further, the first predetermined cycle (cycle time T) and the second predetermined cycle (trigger waiting time Tr) may be the same or different in the length of the cycle (length of time). Good. In addition, even if partial discharge monitoring is performed by setting the first predetermined cycle and the second predetermined cycle to be one each, the partial discharge monitoring is performed by alternately repeating the first predetermined cycle and the second predetermined cycle. You can go either. For example, in FIG. 3, the first predetermined cycle (cycle time T) and the second predetermined cycle (trigger waiting time Tr) are alternately set a plurality of times at the same time length.

  Further, the threshold setting method is not limited from <Threshold setting method (1)> to <Threshold setting method (6)>. Any device that “sets a threshold value based on a measurement value within a first predetermined period of a partial discharge detection signal” is included in the scope of the present embodiment.

  According to the discharge monitoring apparatus of the present invention, it is possible to reduce the amount of data used for discharge monitoring and to monitor discharge for a long time. Therefore, it is possible to monitor the occurrence of partial discharge in the existing equipment for a long period of time and to repair the equipment or update the equipment before the failure occurs.

DESCRIPTION OF SYMBOLS 1 Discharge monitoring apparatus 2 Data processing part 3 Data recording part 4 Communication part 5 Sensor part 6 Data analysis part 21 Data sampling part 22 Threshold measurement part 23 Trigger timing measurement part 24 Measurement timing signal processing part 25 1st peak measurement part 26 1st 2 peak measurement unit 31 threshold recording unit 32 single pulse waveform data recording unit 33 q-φ characteristic data recording unit 41, 42 communication device 51 partial discharge detection sensor 52 humidity sensor 53 ammeter 61 data server 71 high voltage power distribution device 72 High voltage AC power supply

The present invention is a discharge monitoring apparatus for monitoring the discharge of a power receiving / distributing device , and a measured value within a first predetermined period of a discharge detection signal detected by a discharge detection sensor attached to the power receiving / distributing device. And a data processing unit for measuring whether or not the level of the discharge detection signal exceeds the threshold within a second predetermined period, and the level of the discharge detection signal is set to a second predetermined level . generating a trigger signal when it exceeds the hand the threshold cycle, similar timing the trigger signal is generated, a data recording unit for recording the single pulse waveform data of the discharge detection signal, the single pulse waveform data And a communication unit that transfers the data to the data analysis unit.

Further, in the discharge monitoring apparatus according to the present invention, the threshold value may be an Nth largest value (where N is an arbitrary numerical value equal to or greater than 2) within a first predetermined period of the discharge detection signal. it can.

Further, in the discharge monitoring apparatus according to the present invention, the data processing unit includes a plurality of peak measuring units having different peak value acquisition timings, and the discharge detection signal for each unit time obtained by dividing the first predetermined period into a plurality of units. the peak value, depending on the measurement timing of the peak measurement unit, measured at the peak measurement unit, in the data recording section, the peak values of different measurement timing measured at each peak measurement unit The peak data combined and arranged in the order of measurement timing is recorded, and the single pulse waveform data is recorded using the threshold set based on the peak value, and the peak data is recorded together with the single pulse waveform data in the communication unit. It is preferable to transfer.

Further, the present invention is a discharge monitoring method for monitoring the discharge of a power receiving / distributing device, wherein the discharge detecting signal is detected by a discharge detecting sensor attached to the power receiving / distributing device within a first predetermined period. A step of setting a threshold based on the measured value, a step of measuring whether or not the signal level of the discharge detection signal exceeds the threshold within a second predetermined period, and the level of the discharge detection signal generating a trigger signal when it exceeds the hand the threshold second predetermined period within similar timing the trigger signal is generated, the step of recording the single pulse waveform data of the discharge detection signal, the single pulse waveform data And a step of transferring the data to the data analysis unit.

Claims (18)

A discharge monitoring device for monitoring the discharge of power receiving and distributing equipment,
Whether a threshold value is set based on a measurement value within a first predetermined period of the discharge detection signal emitted from the power receiving and distributing device, and whether the level of the discharge detection signal exceeds the threshold value within the subsequent second predetermined period A data processing unit for measuring whether or not,
A data recording unit that records single pulse waveform data of the discharge detection signal, triggered by a timing that exceeds the threshold within the second predetermined period,
A communication unit for transferring the single pulse waveform data to a data analysis unit;
A discharge monitoring apparatus comprising:   The discharge monitoring apparatus according to claim 1, wherein the threshold value is a maximum value within a first predetermined period of the discharge detection signal.   The discharge monitoring apparatus according to claim 1 or 2, wherein the threshold value is a value obtained by multiplying a maximum value within a first predetermined period of the discharge detection signal by a coefficient.   The discharge monitoring apparatus according to any one of claims 1 to 3, wherein the threshold value is an Nth largest value within a first predetermined period of the discharge detection signal.   The discharge monitoring apparatus according to any one of claims 2 to 4, wherein the threshold value is set in a specific phase range within a first predetermined period of the discharge detection signal.   The discharge detection signal acquired within the first predetermined period is divided into signal levels, the number of data having a peak value at each signal level is measured, and based on the number of data from the largest signal level, 5. The discharge monitoring apparatus according to claim 2, wherein a signal level range for threshold setting is determined, and the threshold is set within the signal level range. 6.   7. The discharge according to claim 6, wherein the threshold value is set in the signal level range equal to or less than the Nth minimum value when viewed from the largest signal level, with a minimum value equal to or less than a predetermined number of data. Monitoring device.   The discharge monitoring apparatus according to claim 7, wherein the minimum value is zero in the number of data. In the data processing unit, the peak value of the discharge detection signal is measured every unit time obtained by dividing the first predetermined period into a plurality of times,
The data recording unit records peak data obtained by combining the peak values, and records the single pulse waveform data using the threshold value set based on the peak value,
The discharge monitoring apparatus according to claim 1, wherein the communication unit transfers the peak data together with the single-shot pulse waveform data.   The data processing unit includes a plurality of peak measurement units having different peak value acquisition timings, and the data recording unit records the peak data by combining the peak values measured by the peak measurement units. The discharge monitoring apparatus according to claim 9.   The discharge according to claim 9 or 10, wherein the data processing unit generates a measurement timing signal based on power phase information and measures the peak value based on the measurement timing signal. Monitoring device.   The discharge monitoring apparatus according to any one of claims 1 to 11, further comprising the data analysis unit that performs discharge analysis based on transfer data from the communication unit.   The discharge monitoring apparatus according to any one of claims 1 to 12, further comprising a sensor unit that acquires a discharge detection signal emitted from the power receiving and distributing device.   The sensor unit acquires ambient environment information of the power receiving / distributing device, operating status information of the power receiving / distributing device, or the ambient environment information and the operating status information that can be used to determine whether discharge has occurred. The discharge monitoring apparatus according to claim 13.   The discharge monitoring apparatus according to any one of claims 1 to 14, wherein the data recording unit records the single pulse waveform data by going back a recording time by a predetermined time from a trigger timing.   The discharge monitoring apparatus according to any one of claims 1 to 15, wherein the data processing unit updates the measurement of the threshold value every first predetermined period.   The discharge monitoring apparatus according to any one of claims 1 to 16, wherein the data processing unit samples the discharge detection signal at a sampling frequency of 1 GHz or more. A discharge monitoring method for monitoring the discharge of power receiving and distributing equipment,
Setting a threshold based on a measured value within a first predetermined period of a discharge detection signal emitted from the power receiving and distributing device;
Measuring whether or not the signal level of the discharge detection signal exceeds the threshold within a second predetermined period that follows,
Recording a single pulse waveform data of the discharge detection signal, triggered by a timing exceeding the threshold within the second predetermined period;
Transferring the single pulse waveform data to a data analysis unit;
A discharge monitoring method comprising:

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