JP6246058B2 - Discharge detection device and discharge detection method for vacuum switchgear - Google Patents

Description

  The present invention relates to a discharge detection device and a discharge detection method for a vacuum switchgear.

  The vacuum valve includes a pair of contacts, which are a fixed contact and a movable contact disposed so as to face the fixed contact, and the pair of contacts are disposed in a vacuum container in which the periphery of the contact is kept in a vacuum. . When the contact of the vacuum valve is turned on and the current flowing through the main circuit conductor is opened, the contact of the vacuum valve is opened to cut off the current flowing through the main circuit. The current is interrupted by the arc extinguishing capability. However, when the degree of vacuum in the vacuum vessel decreases due to the occurrence of cracks in the vacuum vessel, the release of gas molecules adsorbed on metals and insulators, and the permeation of atmospheric gas, the contacts are opened. Insulation breakdown occurs and the current cannot be cut off, and in the worst case, the equipment is damaged. Therefore, in order to grasp the state of the vacuum valve without damaging the circuit breaker using the vacuum valve and its peripheral devices, a vacuum degree deterioration monitoring device for determining whether the degree of vacuum in the vacuum vessel is deteriorated has been studied. It was.

  For example, a vacuum degree monitoring device as a discharge detection device of a conventional vacuum switchgear is caused by the deterioration of the vacuum degree of a vacuum circuit breaker as a vacuum valve and the breakdown voltage performance is lowered, so that discharge occurs, and electromagnetic waves accompanying the discharge are generated. The degree of vacuum is determined by detecting with a probe or an antenna (for example, see Patent Document 1). In addition, an insulation diagnosis device as a discharge detection device of another conventional vacuum switchgear repeatedly measures the sound wave at the time of discharge and counts the number of discharges received in a certain period of time repeatedly. Then, the obtained data is statistically processed and insulation deterioration diagnosis is performed from the cumulative frequency distribution (see, for example, Patent Document 2). Further, as a vacuum failure detection device as a discharge detection device of other conventional vacuum switchgears, there is a possibility that discharge will occur due to aging deterioration of the outer surface of the vacuum valve, the insulating member in the circuit breaker, etc. In order to discriminate from discharge due to deterioration of the degree of vacuum, discharge occurs once in half cycle at 0.1-0.2 Torr, and discharge occurs more than twice in half cycle at 0.2-0.5 Torr, resulting in insulation deterioration In this case, since discharge is intermittently generated, it is determined whether the degree of vacuum is reduced or the insulation is deteriorated (for example, see Patent Document 3).

JP 59-160924 A (page 4, lines 13 to 30 and FIG. 13) JP-A-60-010184 (page 2, upper left column, line 17 to page 3, lower left column, line 13 and FIGS. 1 to 4) JP-A-02-044624 (page 3, lower right column, line 5 to page 5, upper left column, second line, FIGS. 1 and 2)

  In the vacuum degree monitoring device described in Patent Document 1, although the determination of the quality of the vacuum degree of the vacuum valve (vacuum circuit breaker) is described, the detection method of discharge due to insulation deterioration and the discharge due to vacuum degree deterioration are described. There was a problem that the identification method was not considered. The insulation diagnostic device described in Patent Document 2 describes insulation diagnosis of a solid insulator of an electric device, but touches on detection of a decrease in the degree of vacuum in a vacuum valve and detection of insulation deterioration of the insulator of a vacuum valve. It is not done. Further, in the vacuum defect detection device described in Patent Document 3, when the determination is made based on the number of discharges that occur in a half cycle, the discharge that occurs when the degree of vacuum is reduced is not necessarily once in a half cycle. It can be determined only in the range of 1-0.5 Torr, and if it is 0.1 Torr or less or 0.5 Torr or more, it is necessary to check whether the degree of vacuum is low or insulation is deteriorated, and the check work takes time. There was a point.

  The present invention has been made to solve the above-described problems, and determines the deterioration of the vacuum degree of the vacuum valve or the insulation deterioration of the insulating member of the vacuum valve or the contact insulating member arranged in contact with the vacuum valve. An object of the present invention is to obtain a discharge detection device for a vacuum switchgear that can be performed and to provide a discharge detection method. It is another object of the present invention to provide a discharge detection device for a vacuum switchgear that can determine the degree of vacuum in a vacuum bulb if the degree of vacuum is reduced, and can determine the amount of discharge charge if it is caused by insulation deterioration.

In the discharge detection device of the vacuum switchgear according to the present invention,
Detecting discharge of a vacuum switching device having a vacuum valve that opens and closes a main circuit and a contact insulating member provided in contact with the vacuum valve, and includes an electromagnetic wave detection unit, a counting unit, and a determination unit ,
The electromagnetic wave detection unit detects the magnitude of an electromagnetic wave due to discharge in the vacuum switchgear,
The counting unit repeats the operation of counting the excess number N, which is the number that the magnitude of the electromagnetic wave exceeds a preset threshold value during a predetermined time, to obtain M excess number data by repeating the operation a predetermined number of times M, The data number D of the excess number data in which the excess number N exceeds the predetermined value among the M excess number data is obtained.
The determination unit determines that the vacuum valve has a reduced degree of vacuum when the ratio γ = D / M of the number of data D with respect to the predetermined number of times M exceeds a predetermined value, and when the ratio γ is equal to or less than a predetermined value. It is determined that the insulating member of the vacuum valve or the contact insulating member is deteriorated in insulation.

The discharge detection method for a vacuum switchgear according to the present invention is a method for detecting discharge of a vacuum switchgear having a vacuum valve that opens and closes a main circuit and a contact insulating member provided in contact with the vacuum valve. And having the following steps.
A. Detecting a magnitude of an electromagnetic wave caused by discharge in the vacuum bulb.
A. The operation of counting the excess number N, the magnitude of the electromagnetic wave exceeding a preset threshold during a predetermined time, is repeated M times a predetermined number of times to obtain M excess number data, and the M excess number A step of obtaining the data number D of the excess number data in which the excess number N exceeds a predetermined value.
C. When the ratio γ = D / M of the number of data D with respect to the predetermined number of times M exceeds a predetermined value, it is determined that the vacuum degree of the vacuum valve is lowered, and when the ratio γ is equal to or lower than the predetermined value, the vacuum valve is insulated. The process of determining with the insulation deterioration of a member or the said contact insulation member.

  Since the discharge detecting device of the vacuum switchgear according to the present invention is configured as described above, the vacuum degree of the vacuum valve is reduced and the insulating material of the vacuum valve or the insulation of the contact insulating member provided in contact with the vacuum valve is insulated. Degradation can be determined.

  Since the discharge detection method for a vacuum switchgear according to the present invention includes the steps as described above, the vacuum degree of the vacuum valve is lowered and the insulation deterioration of the contact insulating member provided in contact with the insulating material of the vacuum valve or the vacuum valve is provided. Can be determined.

It is a block diagram which shows the structure of the discharge detection apparatus of the vacuum switchgear which is Embodiment 1 of this invention. 2A is a perspective view showing a state in which the discharge detection device of the vacuum switching device of FIG. 1 is attached to the circuit breaker, and FIG. 2B is a cross-sectional view showing details of the support state of the vacuum valve. It is a flowchart which shows operation | movement of the discharge detection apparatus of a vacuum switchgear. It is a figure which shows the excess data at the time of a vacuum degree fall. It is a figure which shows the excess data at the time of insulation degradation. It is a block diagram which shows the structure of the discharge detection apparatus of the vacuum switching device by Embodiment 2. It is a flowchart which shows operation | movement of the vacuum degree calculation part of FIG. It is a characteristic view which shows the relationship between the peak value of electromagnetic waves, and the vacuum degree of a vacuum valve. FIG. 10 is a block diagram illustrating a configuration of a discharge detection device of a vacuum switching device according to a third embodiment. 10 is a flowchart illustrating an operation of a discharge charge amount calculation unit in FIG. 9. It is a characteristic view which shows the relationship between the peak value of electromagnetic waves, and the amount of discharge charges by deterioration of an insulating member. It is a block diagram which shows the structure of the discharge detection apparatus of the vacuum switching device by Embodiment 4. It is a flowchart which shows operation | movement of the discharge detection apparatus of the vacuum switchgear of FIG. It is a flowchart which shows the detail of step S40 of FIG.

Embodiment 1 FIG.
1 to 5 show a first embodiment for carrying out the present invention. FIG. 1 is a block diagram showing a configuration of a discharge detection device of a vacuum switchgear, and FIG. 2 (a) is a diagram of FIG. FIG. 2B is a perspective view showing a state in which the discharge detection device of the vacuum switchgear is attached to the circuit breaker, and FIG. FIG. 3 is a flowchart showing the operation of the discharge detecting device of the vacuum switching device, FIG. 4 is a diagram showing excess number data when the degree of vacuum is lowered, and FIG. 5 is a diagram showing excess number data when insulation is deteriorated. 1 and 2, the circuit breaker 1 as a vacuum switching device includes a bushing 10, a container 13, a vacuum valve 16, and a driving device 17. The bushing 10 includes a soot tube 11, a bushing conductor 12 that penetrates the soot tube 11, and an electric field relaxation shield 14. A vacuum vessel 16 that cuts off a main circuit current and an accident current is accommodated in a cylindrical container 13 made of a conductor such as a steel plate or aluminum having a ground potential. The container 13 has airtightness and is filled with an insulating gas.

  As shown in FIG. 2B, the vacuum valve 16 includes a cylindrical insulating tube 16a, left and right end plates 16b and 16c, a fixed electrode 16d, a movable electrode 16e, and a bellows 16f. Metal end plates 16b and 16c are brazed to both ends of the insulating cylinder 16a in the axial direction, the fixed electrode 16d is provided airtightly through the left end plate 16b, and the movable electrode 16e is connected to the fixed electrode 16d. The insulating cylinder 16a is evacuated by being brazed so as to be airtight and axially movable to a metal bellows disposed opposite to the right end plate 16c. As shown in FIG. 2B, the vacuum electrode 16 is fixedly supported on the left inner surface of the container 13 through the insulating support member 19 on the fixed electrode 16 d side. The fixed electrode 16 d and the movable electrode 16 e of the vacuum valve 16 are each connected to the bushing conductor 12. The movable electrode 16e is moved in the axial direction while sliding with respect to the bushing conductor 12, and energization between both is possible.

  The drive device 17 includes a drive device main body 17a and an insulating rod 17b. The driving device main body 17a is fixed to the outer side surface (see FIG. 2A) of the right end of the container 13, and is coupled to the movable electrode 16e of the vacuum valve 16 via the insulating rod 17b. The valve 16 is opened / closed by driving in the axial direction of the valve 16 to make contact with / separate from the fixed electrode 16d. As described above, the vacuum valve 16 is insulated from the container 13 and the drive device main body 17a as a ground potential member by the insulating support member 19 as a contact insulating member provided in contact with the vacuum valve 16 and the insulating rod 17b. ing.

  Further, a bushing 10 for connecting to the outside is attached to the container 13. The bushing conductor 12 is provided with a cylindrical electric field relaxation shield 14 that partially covers the outer periphery thereof. Since the electric field relaxation shield 14 has a capacitive component with the bushing conductor 12, it acts as a low-pass filter. The discharge detection device includes an antenna 2 as an electromagnetic wave detection unit and a discharge detection device main body 110. The antenna 2 is installed inside the container 13. A band with good reception sensitivity of the antenna 2 is set to a frequency band of electromagnetic waves due to discharge, which is equal to or lower than the cutoff frequency of the electric field relaxation shield (low-pass filter) 14. The discharge detection device main body 110 includes a demultiplexing unit 4, a detection unit 5, a counting unit 6, a determination unit 7, and a display unit 8. The output side of the antenna 2 is connected to the demultiplexing unit 4 of the discharge detection device main body 110 by a signal line 18.

  Next, the operation will be described. When an insulation problem occurs in the container 13, for example, metal foreign matter adheres to a high electric field portion in the vacuum valve 16, or a solid insulating member around the vacuum valve 16 (for example, an insulating rod for driving a movable electrode, a ceramic product) In the case of poor insulation of the vacuum container or the like, or deterioration of the vacuum degree in the vacuum valve 16, partial discharge occurs in the container 13 and electromagnetic waves are emitted. At this time, an electromagnetic wave due to discharge propagates to the antenna 2. The electromagnetic wave received by the antenna 2 is input as the electromagnetic wave S <b> 1 to the demultiplexing unit 4 through the signal line 18. The demultiplexing unit 4 extracts an electromagnetic wave S2 having a frequency equal to or lower than the cutoff frequency of the electric field relaxation shield (low-pass filter) 14, and the peak value (voltage) S3 of the extracted electromagnetic wave S2 (for example, frequency 200 to 300 MHz) is detected by the detection unit 5. Take out.

  Hereinafter, a method of detecting the discharge of the vacuum bulb 16 based on the peak value S3 of the electromagnetic wave S2 detected and extracted will be described with reference to the flowchart of FIG. In FIG. 3, initialization (measurement number n = 1) is performed (step S1), and a predetermined time Δt, which is a time predetermined by the counting unit 6, is set as a measurement time per time, and within the predetermined time Δt. An excess number Nn in which the magnitude of the peak value S3 exceeds a predetermined threshold value K set in advance is measured to obtain excess number data Xn (Xn = Nn) (step S2). The obtained excess number data Xn is recorded in the counting unit 6 (step S3). Next, 1 is added to n (step S4), the process returns from step S5 to step S2, and the number of times the magnitude of the peak value S3 exceeds the set threshold value K within the next predetermined time Δt is measured, and the excess number data Xn + 1 is obtained. obtain. This operation is repeated M times that is a predetermined number of times (step S5).

  When the excess number data X1 to XM for M times are obtained (step S5), the determination unit 7 obtains the data number D in which the excess numbers N1 to NM exceed the threshold C among the excess number data X1 to XM (step S6). . Next, a ratio γ = D / M of the number of data D to the number of repetitions M is obtained (step S7). When the ratio γ is equal to or greater than a predetermined value G, which is a predetermined value, since the discharge is continuously generated, it is determined that the vacuum degree of the vacuum bulb 16 is reduced (step S9). Otherwise, since the discharge is intermittently generated, it is determined that the insulation member of the vacuum bulb 16 is deteriorated. Then, the determination result is displayed on the display unit 8 (step S11). The time T of one cycle required for the above determination is T = Δt × M.

  Next, the reason why it is possible to determine whether the discharge source, that is, the cause of the discharge is due to a decrease in the degree of vacuum or the insulation deterioration of the insulating member as described above will be described below. FIG. 4 is a characteristic diagram showing the excess numbers N1 to NM (M = 60) of the measured excess number data X1 to XM when the degree of vacuum is lowered, and FIG. 5 is the measured excess number data X1 to XM when the insulation is deteriorated. It is a characteristic view which shows the excess numbers N1-NM (M = 60). 4 and 5, the excess number data Xn having a large excess number Nn (n = 1 to M) is continuously generated when the degree of vacuum is lowered, whereas the excess number Nn is a value when insulation is deteriorated. It can be seen that there are sections in which the excess number data Xn having zero is continuous and sections in which the excess number data Xn having a relatively small value of the excess number Nn are continuous. From this result, it is possible to count the number of data D where the excess number Nn of the excess number data Xn exceeds the threshold C, and to determine the discharge source from the ratio γ of the data number D to the total number of repetitions M. In FIG. 5, the ratio γ is about 0.87, and in FIG. 6, the ratio γ is about 0.55.

Embodiment 2. FIG.
6 to 8 show the second embodiment, FIG. 6 is a block diagram showing the configuration of the discharge detection device of the vacuum switchgear, FIG. 7 is a flowchart showing the operation of the vacuum degree calculation unit, and FIG. FIG. 6 is a characteristic diagram showing the relationship between the peak value of and the vacuum degree of the vacuum valve 16. In FIG. 6, the discharge detection device main body 210 includes a storage unit 21 and a vacuum degree calculation unit 22. Since other configurations are the same as those in the first embodiment shown in FIG. 1, the corresponding components are denoted by the same reference numerals and description thereof is omitted.

  Next, the operation will be described with reference to FIG. The flowchart of FIG. 7 is inserted between step S9 and step S11 of the flowchart of FIG. 3 of the first embodiment. The storage unit 21 always stores the peak value (voltage) S3 of the electromagnetic wave S2. In step S8 of FIG. 3, it is determined whether or not γ (D / M)> G. If γ> G, it is determined that the degree of vacuum is reduced (step S9). In step S21, the degree of vacuum of the vacuum valve 16 is obtained based on the peak value S3 of the electromagnetic wave S2 stored in the storage unit 21 (details will be described later). Then, the obtained degree of vacuum is displayed on the display unit 8 (step S22). The degree of vacuum in step S21 is obtained based on the characteristics shown in FIG. FIG. 8 shows that a vacuum valve capable of changing the degree of vacuum is installed in the container 13, and a voltage is applied between the main electrodes (fixed electrode and movable electrode) in an open state while changing the degree of vacuum, and then discharged. At that time, the relationship between the electromagnetic wave S1 acquired by the antenna 2 installed in the container 13 and the peak value S3 (voltage) of the electromagnetic wave S2 and the vacuum degree P of the vacuum valve was obtained via the demultiplexing unit 4 and the detection unit 5. FIG. For example, a regression line is calculated by the least square method or the like, and the relationship between the degree of vacuum P and the peak value S3 of the electromagnetic wave S2 is stored in the vacuum degree calculation unit 22, and the degree of vacuum is calculated based on the regression line. Find P.

  As shown in FIG. 8, the peak value of the electromagnetic wave from the antenna tends to be substantially proportional to the degree of vacuum. With this configuration, the degree of vacuum in the vacuum valve can be determined from the peak value (magnitude) of the electromagnetic wave from the antenna, so that the vacuum valve can be opened or closed, that is, the main circuit current can be interrupted, or the vacuum valve needs to be replaced. Such a determination can be made immediately, and a work process for determining the generation source when a discharge occurs can be reduced, and the work time can be reduced.

Embodiment 3 FIG.
9 to 11 show the third embodiment, FIG. 9 is a block diagram showing the configuration of the discharge detection device of the vacuum switchgear, FIG. 10 is a flowchart showing the operation of the discharge charge amount calculation unit, and FIG. It is a characteristic view which shows the relationship between the peak value of electromagnetic waves, and the amount of discharge charges. In FIG. 9, the discharge detection device main body 310 includes a discharge charge amount calculation unit 31 instead of the degree of vacuum calculation unit 22. Since other configurations are the same as those of the second embodiment shown in FIG. 6, the corresponding components are denoted by the same reference numerals and description thereof is omitted.

  Next, the operation will be described with reference to FIG. The flowchart of FIG. 10 is inserted between step S10 and step S11 of the flowchart of FIG. 3 of the first embodiment. When it is determined whether or not γ (D / M)> G (G is a predetermined value) in step S8 of FIG. 3, and if γ> G is not determined, the insulation deterioration is determined (step S10). In step S31 of FIG. 10, the discharge charge amount of the discharge is obtained based on the peak value S3 of the electromagnetic wave S2 stored in the storage unit 21 (details will be described later). If the obtained discharge charge amount is at a level that does not cause a problem (step S32), the obtained discharge charge amount is displayed on the display unit 8 and the process is terminated (step S34). If there is a problem in the level, an alarm for insulation deterioration is issued (step S33), and the obtained discharge charge amount is displayed on the display unit 8 (step S34). Insulating members having a high possibility of deterioration of insulation include an insulating cylinder 16a of the vacuum valve 16, an insulating support member 19 as a contact insulating member provided in contact with the vacuum valve 16, and an insulating rod 17b. According to the form, detection is possible even if any of these is deteriorated in insulation.

  FIG. 11 shows the magnitude of the electromagnetic wave received by the antenna 2 installed in the container 13 while an insulating member whose insulation has been deteriorated in advance is installed in the container 13 and the discharge charge amount is changed by changing the applied voltage or the like. It is a characteristic view which shows the result of having measured the relationship between length (peak value S3) and the amount Q of discharge charges. According to FIG. 11, the electromagnetic wave (peak value S3) from the antenna 2 tends to increase as the discharge charge amount Q increases. Based on this measurement result, a regression line indicating the relationship between the discharge charge amount Q and the peak value S3 of the electromagnetic wave from the antenna 2 is obtained by the least square method or the like, similar to the vacuum degree calculation described in the second embodiment. It is stored in the charge amount calculation unit 31, and the discharge charge amount Q is obtained from the peak value S3 using this regression line.

  As described above, according to this embodiment, since the discharge charge amount Q is found, it is possible to immediately determine how much the insulating member has deteriorated, whether the insulating member needs to be replaced, etc. It is possible to reduce work processes such as time investigation.

Embodiment 4 FIG.
FIGS. 12 to 14 show the fourth embodiment, FIG. 12 is a block diagram showing the configuration of the discharge detection device of the vacuum switchgear, and FIG. 13 is a flowchart showing the operation of the discharge detection device of the vacuum switchgear. FIG. 14 is a flowchart showing details of step S40 in FIG. In FIG. 12, the discharge detection device main body 410 includes a vacuum degree calculation unit 22, a discharge charge amount calculation unit 31, and a lock unit 41 as an opening / closing operation prohibition unit. Since other configurations are the same as those in the second embodiment shown in FIG. 6 or the third embodiment shown in FIG. 9, the same components are denoted by the same reference numerals and description thereof is omitted.

  In this embodiment, the second embodiment and the third embodiment are combined, and a lock portion 41 is provided to prohibit the opening / closing operation of the vacuum valve 16 when necessary. In the flowchart of FIG. 13, steps S1 to S7 are the same as in the first embodiment, but the subsequent operation in step S40 is different. In FIG. 14 showing the details of step S40, steps S8 to S34 are the same steps as in the first to third embodiments. In FIG. 14, when the calculation result of the degree of vacuum obtained by the degree-of-vacuum calculation unit 22 is not a degree of vacuum that can interrupt a predetermined current, for example, the rated current of the circuit breaker 1, that is, a degree of vacuum that cannot be opened (step). S41), an opening / closing circuit (not shown) is locked by the lock unit 41 so that the driving device 17 does not operate, and the opening / closing operation is prohibited (step S42). The lock and the degree of vacuum are displayed on the display unit 8 (step S45). If the degree of vacuum that can be opened, that is, the main circuit current can be interrupted but a large current exceeding the rated current, such as an accident current, may not be interrupted (step S41), an alarm for lowering the degree of vacuum is issued (step S41). S44) The fact that the degree of vacuum is reduced and the accident current cannot be interrupted and the degree of vacuum are displayed on the display unit 8 (step S45).

  In each of the above-described embodiments, the monitoring of the discharge of the vacuum bulb and the determination of the degree of vacuum and the discharge charge amount based on the peak value S3 of the electromagnetic wave S1 are shown. However, the embodiments are not limited to those obtained from the peak value S3. Alternatively, it can be obtained based on the magnitude of another form of electromagnetic wave obtained by appropriately processing the electromagnetic wave S1.

  As described above, according to this embodiment, when the degree of vacuum of the vacuum valve is deteriorated and the load current cannot be cut off, that is, the level at which the flashing occurs at the moment of opening, the contact is erroneously opened. Since this can be prevented, safety can be further improved. Also, if the vacuum level drops to a level where the load current can be cut off but a large current exceeding the load current such as an accident current cannot be cut off, an alarm is given to notify the vacuum degree deterioration. Countermeasures are possible.

In the above description, since the vacuum valve 16 is accommodated in the conductive container 13, the antenna 2 installed in the container 13 does not receive electromagnetic noise from the outside, so that countermeasures against electromagnetic noise are easy. Even if it is not housed, it can be applied. Further, the case where the vacuum switch is a vacuum circuit breaker has been described above, but the same effect can be obtained even with other vacuum switches such as a vacuum electromagnetic contactor.
In the present invention, the above-described embodiments can be freely combined within the scope of the invention, or each embodiment can be appropriately changed or omitted.

1 circuit breaker, 2 antenna, 6 counting unit, 7 judging unit, 8 display unit, 13 container,
16 vacuum valve, 16a insulating cylinder, 17 driving device, 17b insulating rod,
19 insulating support member, 21 storage unit, 22 vacuum degree calculation unit, 31 discharge charge amount calculation unit,
41 Lock part, 110, 210, 310, 410 Discharge detection device body.

Claims (8)

Detecting discharge of a vacuum switching device having a vacuum valve that opens and closes a main circuit and a contact insulating member provided in contact with the vacuum valve, and includes an electromagnetic wave detection unit, a counting unit, and a determination unit ,
The electromagnetic wave detection unit detects the magnitude of an electromagnetic wave due to discharge in the vacuum switchgear,
The counting unit repeats the operation of counting the excess number N, which is the number that the magnitude of the electromagnetic wave exceeds a preset threshold value during a predetermined time, to obtain M excess number data by repeating the operation a predetermined number of times M, The data number D of the excess number data in which the excess number N exceeds the predetermined value among the M excess number data is obtained.
The determination unit determines that the vacuum valve has a reduced degree of vacuum when the ratio γ = D / M of the number of data D with respect to the predetermined number of times M exceeds a predetermined value, and when the ratio γ is equal to or less than a predetermined value. A discharge detection device for a vacuum switchgear that determines an insulation deterioration of the insulating member of the vacuum valve or the contact insulating member. A storage unit and a vacuum degree calculation unit;
The storage unit repeats the operation of storing the magnitude of the electromagnetic wave during the predetermined time M times the predetermined number of times,
The vacuum degree calculation unit obtains the vacuum degree of the vacuum valve based on the magnitude of the electromagnetic wave stored in the storage unit when the determination unit determines that the vacuum degree of the vacuum valve is reduced. The discharge detection device of the vacuum switchgear according to claim 1. A storage unit and a discharge charge amount calculation unit;
The storage unit repeats the operation of storing the magnitude of the electromagnetic wave during the predetermined time M times the predetermined number of times,
The discharge charge amount calculation unit is configured to determine a discharge charge amount based on the magnitude of the electromagnetic wave stored in the storage unit when the determination unit determines that the insulation deterioration of the insulating member of the vacuum valve or the contact insulating member. The discharge detection device for a vacuum switchgear according to claim 1, wherein: A storage unit, a degree of vacuum calculation unit, and a discharge charge amount calculation unit;
The storage unit repeats the operation of storing the magnitude of the electromagnetic wave during the predetermined time M times the predetermined number of times,
The vacuum degree calculation unit obtains the vacuum degree of the vacuum valve based on the magnitude of the electromagnetic wave stored in the storage unit when the determination unit determines that the vacuum degree of the vacuum valve is reduced. The discharge charge amount calculation unit is configured to determine a discharge charge amount based on the magnitude of the electromagnetic wave stored in the storage unit when the determination unit determines that the insulation deterioration of the insulating member of the vacuum valve or the contact insulating member. The discharge detection device for a vacuum switchgear according to claim 1, wherein: It has an open / close prohibited part,
The discharge detection device of a vacuum switching device according to claim 2 or 4, wherein the opening / closing prohibiting unit prohibits an opening / closing operation of the vacuum valve based on the degree of vacuum. The vacuum opening and closing device has at least one of an insulating support member for supporting the vacuum valve and an insulating rod for opening and closing the vacuum valve by a driving device,
The discharge detection device for a vacuum switchgear according to claim 1, wherein the contact insulating member is at least one of the insulating support member and the insulating rod. The vacuum valve is housed in a container filled with an insulating gas,
The discharge detection device for a vacuum switchgear according to any one of claims 1 to 6, wherein the electromagnetic wave detection unit is installed in the container. A method for detecting discharge of a vacuum switchgear having a vacuum valve for opening and closing a main circuit and a contact insulating member provided in contact with the vacuum valve, the method comprising:
A. Detecting a magnitude of an electromagnetic wave caused by discharge in the vacuum bulb.
A. The operation of counting the excess number N, the magnitude of the electromagnetic wave exceeding a preset threshold during a predetermined time, is repeated M times a predetermined number of times to obtain M excess number data, and the M excess number A step of obtaining the data number D of the excess number data in which the excess number N exceeds a predetermined value.
C. When the ratio γ = D / M of the number of data D with respect to the predetermined number of times M exceeds a predetermined value, it is determined that the vacuum degree of the vacuum valve is lowered, and when the ratio γ is equal to or lower than the predetermined value, the vacuum valve is insulated. The process of determining with the insulation deterioration of a member or the said contact insulation member.

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