JP2010073984A - Partial discharge diagnostic device of stationary inductive electric apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a partial discharge diagnostic device for a stationary inductive electric apparatus which obtains excellent partial discharge detecting sensitivity and facilitates maintenance or exchange. <P>SOLUTION: A transformer tank 1 is connected to a sensor receiving vessel 7 through a butterfly valve 9. The partial discharge detecting sensor 10 composed of a signal detecting unit 11 and a sensor supporting unit 12 is attached to the tip of a sensor inserting rod 13 formed of metal and having a shape of a pipe, and a signal cable 14 is arranged in the sensor inserting rod 13 while the signal cable 14 is connected to an external terminal 16. The sensor inserting rod 13 is constituted so that the partial discharge detecting sensor 10, arranged at one end thereof is installed in the sensor receiving vessel 7 and the other end is extracted to the outside through an opening unit 7a formed at the sensor receiving vessel 7 so as to be supported slidably by a rod supporting cylinder 17 while the partial discharge detecting sensor 10 can be moved between the transformer tank 1 and the sensor receiving vessel 7. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a partial discharge diagnostic apparatus for static induction electrical equipment such as a gas-insulated transformer using an insulating gas as an insulating medium and a cooling medium, and an oil-filled transformer using insulating oil as an insulating medium and a cooling medium. .

  Conventionally, in order to monitor the insulation performance of a static induction electrical device such as a transformer, a method of detecting the occurrence of partial discharge that occurs before breaking all the paths inside the device has been used. As a method of detecting the partial discharge, there is a method of detecting an electric signal, an acoustic signal, and an optical signal that are simultaneously generated when the partial discharge is generated. In particular, as a partial discharge detection method for power transformers, in general, an ultrasonic sensor attached to the outer wall of the transformer tank detects an ultrasonic signal associated with the partial discharge, or the neutrality of the transformer winding. A method of detecting an electrical pulse signal at a point or the like is used.

  However, various noises that impede detection of partial discharges enter the transformer in an operating state at a substation or the like. Therefore, there is a problem that the detection sensitivity is lowered in the method of detecting the electric pulse signal of the partial discharge at the neutral point of the transformer winding. In addition, in the method of detecting with the acoustic sensor attached to the outer wall of the tank, there is a risk of malfunction that detects sound due to wind and rain, etc., and furthermore, the acoustic signal is attenuated between the tank wall and the acoustic sensor. Similarly, there is a problem that the detection sensitivity is lowered.

  In addition, the sound wave signal detected by this acoustic sensor is a combination of both the direct propagation of insulation oil and gas, which is the medium in the transformer, from the partial discharge source and the signal propagated through the main tank of the transformer. Will be. Normally, the partial discharge position is identified by back-calculating from the propagation time difference of the acoustic signal that has directly propagated through the insulating oil or gas and reached the sensor, but the acoustic sensor attached to the outer wall of the tank propagates through the tank. There is a drawback that the accuracy of the evaluation of the partial discharge position is reduced due to the noise of the acoustic signal.

  Therefore, in order to improve the partial discharge detection sensitivity in the transformer, it is effective to install a detection sensor in the transformer tank. However, it is not easy to install a sensor in the transformer tank and to maintain the installed sensor. For example, if the sensor is to be replaced due to a failure or the like, a large-scale construction such as stopping the operation of the transformer and removing the internal insulator is required, resulting in a large economic loss. In addition, installation of a new sensor inside an existing device that was manufactured without assuming the installation of the sensor and is actually used in the field may require further extensive remodeling work. It was not a realistic way.

  In order to solve such a problem, Patent Document 1 includes a case where the sensor is installed in the transformer by connecting the transformer tank and the container containing the partial discharge detection sensor via a valve. A monitoring device for a stationary induction device capable of detecting a partial discharge with high sensitivity has been proposed.

  FIG. 4 shows an example of attachment of the partial discharge detection sensor disclosed in Patent Document 1. That is, as shown in FIG. 4, a winding 2 and an iron core 3 are housed in a transformer tank 1 to form a transformer. In this transformer tank 1, a surge voltage is measured in the vicinity of the bushing pocket 5. A device 4 is installed. In addition, a sensor housing container 7 that houses an acoustic sensor 6 that detects partial discharge is attached to a side surface of the transformer tank 1 via a valve 8.

In this case, since the compartment on the transformer tank 1 side and the compartment on the sensor storage container 7 side can be easily separated by opening and closing the valve 8, even if a trouble such as a failure occurs in the sensor, the transformer Since the acoustic sensor 6 can be repaired or replaced without removing the insulating oil or insulating gas, which is an insulating medium in the tank 1, it is possible to cope with light and short construction work. There was an advantage that can be easily performed.
JP 2003-217955 A

  However, the above-described mounting structure of the acoustic sensor 6, that is, the partial discharge detection sensor has the following problems. That is, in the conventional type shown in FIG. 4, the acoustic sensor 6 is configured to detect partial discharge in the sensor storage container 7 that is separate from the transformer tank 1. Compared with the case where it is installed in the tank 1, the distance between the partial discharge generation source in the transformer and the installation location of the sensor is longer.

  Further, when the transformer tank 1 and the sensor storage container 7 are viewed as a unit, the partial discharge detection sensor is installed at the bottom of the recess in the transformer tank wall. When the transformer side is viewed from the partial discharge detection sensor at the bottom of the depression, the portion received by the acoustic sensor 6 if the source of partial discharge is in the shadow of the transformer tank 1 and cannot be directly seen, that is, in the blind spot Since the discharge signal is attenuated, the detection sensitivity of the partial discharge is lowered. This detection sensitivity decreases as the cross-sectional area of the recess is smaller and the depth is deeper.

  Furthermore, the partial discharge detection sensitivity also decreases due to the bulb 8 existing between the transformer tank 1 and the sensor storage container 7. That is, a butterfly valve or a gate valve having a large opening area is suitable as the valve 8, but the opening cross-sectional area is reduced as compared with a case where the valve 8 is not installed. In addition, if a structure such as the valve of the valve 8 or its opening / closing shaft is present on the front surface of the partial discharge detection sensor, the propagating partial discharge signal is attenuated by reflection or the like. Become.

  As described above, in a conventional configuration in which partial discharge diagnosis is performed by installing a partial discharge detection sensor such as an acoustic sensor in a container connected to a static induction electrical device via a valve, Compared with the case where a partial discharge detection sensor is installed, there is a problem that the detection sensitivity of partial discharge is lowered. Therefore, the development of a partial discharge diagnostic device for static induction electrical equipment that can obtain the same detection sensitivity as when a partial discharge detection sensor is installed in the tank of the static induction electrical equipment has been desired.

  The present invention has been proposed in order to solve the problems of the prior art as described above, and its purpose is to achieve a partial discharge equivalent to the case where the partial discharge detection sensor is installed in a tank of a static induction electrical device. It is an object of the present invention to provide a partial discharge diagnostic device for static induction electrical equipment that can obtain detection sensitivity and can perform maintenance and replacement of a partial discharge detection sensor without affecting the stationary induction electrical equipment main body.

  In order to achieve the above object, a partial discharge diagnostic apparatus for a static induction electrical device according to claim 1 has a sensor storage container attached to a tank of the static induction electrical device via a valve that can be opened and closed, and a partial discharge detection sensor. Is attached to the tip of the sensor insertion rod, the other end of the sensor insertion rod is pulled out of the sensor storage container, and the sensor insertion rod is moved in the axial direction thereof, thereby opening the valve opening. The partial discharge detection sensor is configured to be able to move between the tank of the static induction electrical device and the sensor storage container via the.

  According to the first aspect of the invention having the above-described configuration, the tank of the stationary induction electrical device and the sensor storage container are partitioned by the openable and closable valve, and when the measurement is performed, the valve is opened to open the sensor insertion rod. Is inserted into the tank side of the static induction electrical device, so that the partial discharge detection sensor can be installed on the tank side of the static induction electrical device. Thereby, the partial discharge detection sensitivity equal to or higher than that when the sensor is installed in the tank of the static induction electrical device can be obtained.

  On the other hand, when sensor installation work or maintenance is required, the tank for stationary induction electrical equipment is pulled out by pulling out the sensor insertion rod, moving the partial discharge detection sensor to the sensor storage container, and closing the valve. Sensor installation work and maintenance can be performed easily.

  According to a third aspect of the present invention, in the partial discharge diagnostic apparatus for static induction electrical equipment according to the first or second aspect, the signal detection surface of the partial discharge detection sensor is in the direction of insertion of the sensor insertion rod. It is characterized by being inclined and supported.

  According to the third aspect of the invention having the above-described configuration, even if there is no diagnosis target portion in the insertion direction of the sensor insertion rod, the signal detection surface of the partial discharge detection sensor can be obtained by rotating the sensor insertion rod. Can be directed to the region to be diagnosed, so that a highly sensitive partial discharge diagnosis is possible.

  According to the present invention, partial discharge detection sensitivity equivalent to the case where the partial discharge detection sensor is installed in the tank of the static induction electrical device is obtained, and maintenance and replacement of the partial discharge detection sensor are performed on the static induction electrical device main body side. It is possible to provide a partial discharge diagnostic apparatus for static induction electrical equipment that can be performed without affecting the apparatus.

  Embodiments of a partial discharge diagnostic apparatus for static induction electrical equipment according to the present invention will be specifically described below with reference to the drawings.

(1) First Embodiment (1-1) Configuration In this embodiment, as shown in FIG. 1, a transformer tank 1 having a winding 2 inside and a sensor storage container 7 include a butterfly valve 9. Connected through. The partial discharge detection sensor 10 includes a signal detection unit 11 and a sensor support unit 12 and is attached to the tip of a sensor insertion rod 13 made of metal and pipe-shaped. Although the butterfly valve 9 is used in the present embodiment, any valve that can pass a sensor or a sensor insertion rod may be used.

  A signal cable 14 for transmitting a partial discharge signal detected by the partial discharge detection sensor 10 to the outside is disposed in the sensor insertion rod 13, and the signal cable 14 is connected to the sensor insertion rod 13. The other end is connected to an external terminal 16 attached via a terminal support 15 so that the sensor output can be taken out.

  The sensor insertion rod 13 has a partial discharge detection sensor 10 disposed at one end thereof installed in the sensor storage container 7 and the other end passing through an opening 7 a formed in the sensor storage container 7. And pulled out. The sensor insertion rod 13 is slidably supported by a rod support cylinder 17 attached to a sensor attachment flange 20 provided outside the opening 7a, so that the transformer tank 1 and the sensor storage container 7 are supported. It is comprised so that it can move between (refer FIG. 1, FIG. 2).

  The rod support cylinder 17 is provided with an O-ring 18, whereby the sensor insertion rod 13 is sealed from the outside, and the rod is inserted in the axial direction of the rod without causing seal leakage. It can be rotated around the center. A stopper 19 for preventing excessive insertion is attached to the sensor insertion rod 13. Furthermore, the sensor storage container 7 is provided with valves 21a and 21b for taking in and out the internal insulating oil or insulating gas.

  When the butterfly valve 9 is in the “open” state, the partial discharge detection sensor 10 is inserted into the transformer tank 1 as shown in FIG. The signal detector 11 is configured to face a measurement object such as the winding 2 in the transformer tank 1. On the other hand, when the open / close state of the butterfly valve 9 is “closed”, the partial discharge detection sensor 10 is configured to be hermetically housed in the sensor housing container 7 as shown in FIG. Yes.

(1-2) Operation According to the present embodiment having the above configuration, the following operation and effect can be obtained. That is, as shown in FIG. 1, when the open / close state of the butterfly valve 9 is “open”, the partial discharge detection sensor is pushed by pushing the sensor insertion rod 13 from the sensor container 7 side to the transformer tank 1 side. 10 can be moved from the compartment on the sensor container 7 side to the compartment on the transformer tank 1 side. Thereby, partial discharge can be measured with high sensitivity equivalent to the case where the partial discharge detection sensor 10 is installed in the transformer tank 1.

  Regarding the insertion depth of the partial discharge detection sensor 10 into the transformer tank 1 when performing the partial discharge diagnosis, as long as the partial discharge detection sensor 10 is at a position that does not affect the insulation of the transformer, the transformer tank It is also possible to position it closer to the transformer than the wall surface of 1, thereby further improving the detection sensitivity of partial discharge.

  On the other hand, as shown in FIG. 2, when the partial discharge measurement is performed with the butterfly valve 9 opened and closed, the partial discharge detection sensor 10 has moved to the compartment on the sensor container 7 side. Only ground noise can be measured. Thereby, if the background noise signal measured in the state of FIG. 2 is subtracted from the partial discharge signal measured in the state of FIG. 1, the noise component superimposed on the partial discharge signal can be largely removed. The discharge detection sensitivity can be further improved.

  Also, if a failure occurs in the partial discharge detection sensor 10 or if it is necessary to make a diagnosis with another type of sensor, the sensor insertion rod 13 is first housed in the sensor from the transformer tank 1 side. Withdrawing to the container 7 side, the partial discharge detection sensor 10 is housed in the sensor housing container 7 and the butterfly valve 9 is closed (FIG. 2). Thereafter, only the insulating oil or insulating gas in the sensor storage container 7 is extracted using the valves 21a and 21b, and the sensor mounting flange 20 is removed from the sensor storage container 7, whereby the partial discharge detection sensor 10 can be taken out. it can. In this case, since the operation of extracting the insulating oil and insulating gas from the transformer tank 1 is not necessary, repair and replacement can be easily performed without affecting the transformer side.

  The partial discharge detection sensor 10 can be used in insulating oil or insulating gas, and can be any type as long as it can withstand the temperature and pressure of insulating oil and insulating gas during transformer operation. A UHF sensor that detects high-frequency radio waves generated at the time of an acoustic wave and an acoustic sensor that detects ultrasonic waves generated during a partial discharge are also applicable.

  In particular, when an acoustic sensor is applied to the partial discharge detection sensor 10, when the butterfly valve 9 is "open", the partial discharge detection sensor 10 is in the transformer tank 1 and is in direct contact with the tank. Therefore, it becomes difficult to detect the sound waves of the partial discharge propagating through the tank wall. For this reason, it is possible to detect a sound wave signal of a partial discharge directly propagating through an insulating medium such as insulating oil or insulating gas from a partial discharge generation source, and it is possible to greatly improve the accuracy of the partial discharge generation position evaluation. .

  In the present embodiment, since the stopper 19 for preventing over-insertion is attached to the sensor insertion rod 13, there is no risk that the sensor insertion rod 13 is excessively inserted into the transformer tank 1. This prevents the risk of dielectric breakdown between the partial discharge detection sensor 10 or the sensor insertion rod 13 and the high-voltage charging part in the transformer by excessively inserting the sensor insertion rod 13 into the transformer tank 1. be able to. Further, although the position of the partial discharge detection sensor 10 cannot be confirmed by direct viewing from the outside, it can be evaluated from the remaining length exposed to the outside of the sensor insertion rod 13.

(1-3) Effect As described above, according to the present embodiment, the partial discharge detection sensor 10 can be moved between the transformer tank 1 and the sensor storage container 7, so that the butterfly valve 9 is opened during measurement. By inserting the sensor insertion rod 13, the sensor can be installed on the transformer tank 1 side. Thereby, the partial discharge detection sensitivity equal to or higher than that when the sensor is installed in the tank of the static induction electrical device can be obtained.

  On the other hand, when installation work or maintenance of the sensor becomes necessary, the sensor can be separated from the transformer tank 1 by moving the sensor to the sensor storage container 7 side and closing the butterfly valve 9. Easy installation and maintenance. Furthermore, the diagnosis apparatus can be installed on an existing static induction electrical device without affecting the inside of the main device. As a result, a highly sensitive partial discharge diagnosis can be realized at low cost, and a highly versatile partial discharge diagnostic apparatus applicable to a wide range of devices can be realized.

(2) Second Embodiment (2-1) Configuration This embodiment is a modification of the first embodiment, and the sensor storage container 7 is located above the transformer tank 1 as shown in FIG. It is attached to the valve at the piping port, and assumes a case where there is no diagnosis target site for partial discharge diagnosis such as the winding 2 at the insertion destination of the sensor insertion rod 13.

  That is, in the present embodiment, the partial discharge detection sensor 30 has the tip end portion of the sensor insertion rod 13 by the sensor support portion 32 so that the detection surface of the signal detection portion 31 faces the diagnosis target site such as the winding 2. It is supported by. It should be noted that the mounting angle of the signal detection unit 31 to the sensor insertion rod 13 can be configured to be adjustable from the outside so as to correspond to the diagnosis target site.

(2-2) Action / Effect According to the present embodiment having the above-described configuration, the following action / effect can be obtained. That is, in the first embodiment, there is a part to be diagnosed for partial discharge diagnosis such as the winding 2 in the insertion direction of the sensor insertion rod 13, and the signal detection unit 11 of the partial discharge detection sensor 10 faces this. By doing so, a highly sensitive partial discharge diagnosis was possible.

  However, even if the existing transformer has a valve or a flange to which the sensor storage container 7 for storing the partial discharge detection sensor as described above can be attached, when the sensor insertion rod is inserted from there, the tip of the container is stored. In addition, there are not always parts to be diagnosed for partial discharge diagnosis such as windings and high-voltage lead wires.

  For example, consider a case where a part of a unit cooler having a plurality of transformers is removed from the transformer, and a sensor storage container is attached to the transformer valve of the removal unit. Usually, the unit cooler is connected to the upper and lower oil piping ports of the transformer tank. Therefore, even if the sensor storage container is attached to the valve of those oil piping ports and the partial discharge detection sensor is inserted inside with the sensor insertion rod, there is a diagnosis target part such as a transformer winding in the insertion direction. It cannot be expected as shown in FIG.

  However, even if there is no part to be diagnosed in the insertion direction of the sensor insertion rod 13, as long as the signal detection unit 31 of the partial discharge detection sensor faces the part to be diagnosed as in this embodiment, the same as in the first embodiment. Highly sensitive partial discharge diagnosis is possible. Therefore, the present embodiment that can effectively utilize the valves and flanges of the existing equipment can be realized with almost no modification work on the main body of the existing equipment, and is economically advantageous.

  Since the sensor insertion rod 13 is rotatable in the circumferential direction of the rod, there is a concern that the rod rotates and the signal detection unit 31 does not face the diagnosis target part. If a mark or the like is attached, the direction of the signal detection unit 31 of the sensor can be easily confirmed even from the outside.

  In addition, suitable valves and manholes for attaching the sensor storage container 7 to an existing static induction electrical device include manholes for storing unit cooler pipe mounting valves and load tap changer (LTC) switchers. Promising. In the case of a unit cooler, when a plurality of unit induction coolers are attached to the static induction electrical device, even if one unit cooler is removed, the operation of the device can be sufficiently performed unless full load operation is performed, and the sensor container 7 is attached to the main body device. The risk of hindering driving is small. In addition, in the manhole for storing the LTC switch, the manhole compartment is separated from the main body of the equipment, so that the modification work for attaching the partial discharge detection sensor can be easily performed.

(3) Other Embodiments The present invention is not limited to the above-described embodiments, and the following modifications can be applied. For example, the partial discharge detection sensors 10 and 30 may require a power source for driving the sensors themselves. There are sensors that have a built-in power supply and can be used without external power supply. However, when continuous measurement is performed for a long time with such a sensor, there is a drawback that the sensor cannot be used because the battery runs out. . Therefore, in such an application, it is desirable to use a sensor that can be driven by supplying power from the outside, or a battery that can be charged from outside by incorporating a rechargeable battery in the sensor itself.

  In this case, power supply from the outside to the partial discharge detection sensors 10 and 30 can be realized by passing the power cable together with the signal cable 14 through the sensor insertion rod 13. Therefore, even when a power supply type sensor is used, online long-term continuous partial discharge diagnosis can be performed.

  Further, since a metallic pipe is used for the sensor insertion rod 13, if the sensor insertion rod 13 is grounded, the signal cable 14 inside the rod can be electrostatically shielded by the sensor insertion rod 13. is there. Furthermore, if the signal cable 14 itself uses a shielded wire such as a coaxial cable, the signal cable 14 itself is double shielded, and the influence of noise received by the signal cable 14 can be suppressed.

  In particular, when a high-frequency electrical signal is transmitted through the signal cable 14, it is necessary to achieve impedance matching at both ends of the signal cable 14. Therefore, it is desirable to use a coaxial cable. Alternatively, it is also possible to install an E / O converter on the sensor side, convert the partial discharge signal into an optical signal, and transmit the signal in the sensor insertion rod 13 by an optical fiber. In the transmission of an optical signal, it is very difficult to be affected by electrical noise, so that a highly sensitive partial discharge diagnosis is possible.

  Moreover, since a metallic pipe is used for the sensor insertion rod 13, it can be used as a waveguide. In this case, the signal cable 14 is not necessary, and a signal transmission antenna may be installed on the partial discharge detection sensor 10 side in the sensor insertion rod 13 and an antenna for receiving it may be installed on the external terminal side. The electromagnetic wave that can be transmitted through the waveguide is an electromagnetic wave that is equal to or higher than the cutoff frequency of the waveguide. Therefore, as a type of the partial discharge detection sensor in this case, a UHF sensor that handles a relatively high frequency component of the partial discharge signal can be applied.

It is a figure which shows the structure of 1st Embodiment of the partial discharge diagnostic apparatus of the static induction electrical equipment which concerns on this invention, Comprising: The case where the opening / closing state of a butterfly valve is "open" is shown. It is a figure which shows the structure of 1st Embodiment of the partial discharge diagnostic apparatus of the static induction electrical equipment which concerns on this invention, Comprising: The case where the opening / closing state of a butterfly valve is "closed" is shown. It is a figure which shows the structure of 2nd Embodiment of the partial discharge diagnostic apparatus of the static induction electrical equipment which concerns on this invention, Comprising: The case where the opening / closing state of a butterfly valve is "open" is shown. It is a figure which shows the example of installation of the partial discharge detection sensor of the conventional static induction electric equipment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transformer tank 2 ... Winding 3 ... Iron core 4 ... Surge voltage measuring device 5 ... Bushing pocket 6 ... Acoustic sensor 7 ... Sensor storage container 8 ... Valve 9 ... Butterfly-shaped valve 10, 30 ... Partial discharge detection sensor 11, 31 Signal detection unit 12, 32 Sensor support unit 13 Sensor insertion rod 14 Signal cable 15 Terminal support base 16 External terminal 17 Rod support cylinder 18 O ring 19 Stopper 20 Sensor mounting flanges 21a and 21b …valve

Claims (9)

The sensor container is attached to the tank of the static induction electrical device through a valve that can be opened and closed.
A partial discharge detection sensor is attached to the tip of the sensor insertion rod, and the other end of the sensor insertion rod is pulled out of the sensor storage container,
By moving the sensor insertion rod in the axial direction, the partial discharge detection sensor can move between the tank of the stationary induction electrical device and the sensor storage container through the opening of the valve. A partial discharge diagnostic apparatus for static induction electrical equipment, characterized in that it is configured as follows.   The partial discharge diagnostic apparatus for static induction electrical equipment according to claim 1, wherein the sensor insertion rod is configured to be rotatable about an axis thereof.   The partial discharge of the static induction electrical device according to claim 1, wherein a signal detection surface of the partial discharge detection sensor is supported while being inclined with respect to an insertion direction of the sensor insertion rod. Diagnostic device.   The said sensor insertion rod is comprised from a metal pipe, and the signal cable for transmitting the output signal of the said partial discharge detection sensor is arrange | positioned inside this pipe. 4. The partial discharge diagnostic device for static induction electrical equipment according to any one of 3 above.   The partial discharge diagnosis apparatus for a stationary induction electrical apparatus according to claim 4, wherein a power cable for driving the partial discharge detection sensor is disposed inside the metal pipe.   According to the insertion depth and / or the rotation angle of the sensor insertion rod, the installation position of the partial discharge detection sensor and the direction of the signal detection surface in the tank of the static induction electrical device can be determined. The partial discharge diagnostic apparatus for static induction electrical equipment according to any one of claims 1 to 5. Close the bulb, store the partial discharge detection sensor in the sensor storage container, measure the background noise signal by performing partial discharge measurement in the sealed sensor storage container,
Open the valve, place the partial discharge detection sensor in the tank of the static induction electrical equipment to measure the partial discharge signal,
7. The apparatus according to claim 1, wherein noise is removed from the partial discharge signal by obtaining a difference between the background noise signal and the partial discharge signal. 8. Partial discharge diagnostic equipment for static induction electrical equipment.   The partial discharge diagnostic apparatus for static induction electrical equipment according to any one of claims 1 to 7, wherein the valve is a butterfly valve.   9. The sensor storage container according to claim 1, wherein the sensor storage container is attached to a pipe mounting valve of a unit cooler of a static induction electrical apparatus or a switcher storage manhole of a load tap switching device. The partial discharge diagnostic device for the static induction electrical apparatus described.

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