JP5504991B2 - Sealed switchboard - Google Patents

Description

  The present invention relates to a hermetic switchboard in which switching devices such as circuit breakers and disconnectors used for power receiving and distribution equipment are housed in a hermetically sealed container.

Sealed switchgears, which are sealed switchboards used in high-voltage and extra-high-voltage power distribution facilities, are mainly used to prevent exposure of live parts, insulation, and environment resistance (protection from adverse environments such as corrosive gases). Circuit devices and charging parts are stored in a sealed container.
As this type of sealed switchboard, for example, three upper and lower sealed containers filled with insulating gas such as dry air are provided in the panel, and the sealed container in which the central disconnector is arranged among these sealed containers A high voltage closed switchboard has been proposed that is sandwiched between sealed containers with circuit breakers, and a dry adsorbent is placed inside each sealed container to maintain the insulating gas in a highly dry state. (For example, refer to Patent Document 1).

  Furthermore, the temperature sensor and the humidity sensor respectively disposed inside and outside the sealed casing, and output signals of these temperature sensor and humidity sensor correspond to the absolute humidity inside and outside the casing. An airtight monitoring device for a housing configured to include a detection circuit that obtains a quantity and outputs a warning signal based on a comparison result of quantities corresponding to the two absolute humidity values, and a warning means that is activated by the output of the detection circuit Has been proposed (see, for example, Patent Document 2).

JP 2009-189129 A Japanese Patent Laid-Open No. 2003-240666

  However, in the conventional example described in Patent Document 1, three sealed containers are required, and when these three sealed containers are connected, it is necessary to maintain airtightness, and between the sealed containers. The electrical connection also requires a bushing to maintain hermeticity in order to penetrate the live part conductor, which makes the coupling structure complex and hinders downsizing, and also monitors hermeticity for each sealed container Therefore, there is an unsolved problem that it is necessary to provide monitoring means such as a pressure sensor and a humidity sensor to increase the cost. Also, a frame is usually provided to support three sealed containers. This frame and the sealed container need to be fixed with fixing screws, but the screw holes need to be kept airtight so that screw holes or studs are raised. Need arises.

Further, in the conventional example described in Patent Document 2, the amounts corresponding to the absolute humidity inside and outside the housing are obtained using the output signals of the temperature sensor and the humidity sensor, respectively. Since the alarm is issued based on the comparison result of the amount corresponding to the absolute humidity, it is not necessary to detect the internal pressure of the sealed container unlike the pressure sensor, so judge the airtightness even in a sealed container close to atmospheric pressure. However, the unsolved problem of the conventional example described in Patent Document 1 cannot be solved.
Therefore, the present invention has been made paying attention to the unsolved problems of the conventional example described above, and by arranging switchgear such as a circuit breaker and a disconnector in one sealed container, the structure of the sealed container is improved. An object of the present invention is to provide a sealed switchboard that can be reduced in size and reduced in manufacturing cost.

In order to achieve the above object, a sealed switchboard according to one embodiment of the present invention is a sealed switchboard used in a power receiving and distribution facility, and includes a switchgear including at least a circuit breaker and a disconnect switch in a sealed container. A protective plate is installed in the sealed container to protect from the charging section when the sealed container is opened , and the protective plate includes an installation space in which the breaker is installed and an installation space in which the disconnector is installed. An insertion hole is formed at the boundary position and through which the connection conductor is inserted .
According to this configuration, since the protective plate for protecting from the charging unit is disposed in the sealed container, there is no need to partition the opening / closing device with a plurality of sealed containers as in the conventional example described above, and the opening and closing is performed with one sealed container. Equipment can be arranged, and the manufacturing cost can be reduced while simplifying the size of the sealed container.

Further, in a closed type distribution board according to another aspect of the present invention, the closed container is arranged in an upper arrangement space and a lower arrangement space with the disconnector and busbars arranged in an intermediate arrangement space, and the intermediate arrangement space is sandwiched therebetween. Each circuit breaker is disposed, and the protection plate is individually disposed between the middle placement space, the upper placement space, and the lower placement space .
According to this configuration, when the inspection is performed with the sealed container opened, adjacent installation spaces can be communicated with each other through at least the insertion hole while reliably protecting the charging unit with the protective plate.

Further, in the sealed switchboard according to one aspect of the present invention, the sealed container is characterized in that a reinforcing concave portion formed of at least one of a U shape and a V shape is formed at one or more corner portions of four corners. Yes.
According to this configuration, since the reinforcing concave portion formed of at least one of the U shape and the L shape is formed at one or more corners of the four corners of the sealed container, the sealed container even when the sealed container is configured by a thin plate having low mechanical strength. The overall strength can be improved.

Further, in a sealed switchboard according to another embodiment of the present invention, a sealed state detecting means for detecting at least one of humidity and dew point is arranged in the sealed container, and the detected value detected by the sealed state detecting means is It is characterized by having a sealing abnormality determination means for determining that there is a sealing abnormality when it is equal to or greater than a preset threshold value.
According to this configuration, the airtightness of the sealed container is detected as humidity or dew point, and when the detected value is equal to or higher than a preset threshold value, it is determined that there is a sealing abnormality, so even if the inside of the sealed container is close to atmospheric pressure The airtightness can be determined to determine a sealing abnormality.

According to the present invention, since the disposed coercive Mamoruban that protects the live parts of the switchgear in a sealed container, when opening the closed container when the switchboard inspection, between live parts of the switchgear by coercive Mamoruban There is no need to provide a sealed container for each open / close device, and various open / close devices can be arranged in one closed container, the sealed container can be reduced in size and airtight. detector to be detected even Ru can reduce the manufacturing cost since it requires only one.

It is a longitudinal cross-sectional view which shows one Embodiment of this invention. It is sectional drawing on the AA line of FIG. It is sectional drawing on the BB line of FIG. It is sectional drawing on the CC line of FIG. It is a top view which expands and shows the corner part of FIG. It is a block diagram which shows a sealing state monitoring apparatus. It is a top view which shows other embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing a sealed switchboard showing an embodiment of the present invention, FIG. 2 is a sectional view taken along the line AA in FIG. 1, and FIG. 3 is a sectional view taken along the line BB in FIG.
In the figure, reference numeral 1 denotes a closed type distribution board, which has inspection opening / closing lids 2a and 2b that can be opened and closed in the middle and lower stages of the front plate part 3F and that is airtight in the closed state, and the same applies to the upper plate part 3U A rectangular parallelepiped sealed container 3 having an inspection opening / closing lid 2c is provided. Here, as shown in FIG. 5, each of the inspection opening / closing lids 2a to 2c is secured with bolts by interposing a packing 4 on the front plate portion 3F and the upper plate portion 3U, thereby ensuring airtightness. It is fixed.

The airtight container 3 has an arrangement space 6 in which an upper circuit breaker 5 serving as an opening / closing device is disposed on the upper side facing the inspection opening / closing lid 2 c, and the inspection opening / closing lid 2 a is disposed below the arrangement space 6. An arrangement space 8 in which the disconnector 7 as the switchgear is arranged is formed opposite to the switchgear, and a lower circuit breaker 9 as the switchgear is arranged below the arrangement space 8 so as to face the inspection opening / closing lid 2b. An arrangement space 10 is formed.
In addition, a cable connecting portion 12 for connecting a T-shaped cable head 11 provided at the tip of an upper R-phase, S-phase, and T-phase three-phase cable is formed on the rear surface corresponding to the arrangement space 6 of the sealed container 3. And a cable connecting portion 14 for connecting a T-shaped cable head 13 provided at the tip of the three-phase cable of the lower R-phase, S-phase and T-phase is formed on the back surface corresponding to the arrangement space 10. Yes.

  And the front-end | tip part in the airtight container 3 of the cable connection part 12 is connected to one connection part of the circuit breaker 5 via the connection conductors 15a-15c, and the other connection part of the circuit breaker 5 connects the connection conductors 16a-16c. And is connected to one of the disconnectors 7. Moreover, the other of the disconnector 7 is connected to one connection part of the circuit breaker 9 via the connection conductors 17a to 17c, and the other connection part of the circuit breaker 9 is connected to the cable connection part 14 via the connection conductors 18a to 18c. It is connected to the tip in the sealed container 3.

Further, as shown in FIGS. 1 and 4, R-phase, S-phase, and T-phase buses 19 a to 19 c are arranged in the sealed container 3 at positions facing the disconnector 7 in the arrangement space 8.
And the protection board 21 which exhibits a protection function with respect to the charged bus-bar 19a in the boundary part with the arrangement | positioning spaces 6 and 8 in the airtight container 3 is shown in FIG. It is bridged and bolted in a horizontal state between the inner surfaces of 3R. As shown in FIG. 3, the protective plate 21 is formed with insertion holes 21 a to 21 c through which connection conductors 16 a to 16 c that electrically connect between the circuit breaker 5 and the disconnecting switch 7 are inserted at the center in the front-rear direction. ing. Here, the protection plate 21 is provided so as to be equal to or less than the gap defined for the object to be protected, and the material may be either an insulator or a conductive metal.

  In addition, a protective plate 22 that protects the load-side charging unit conductor of the disconnector 7 and the charged bus 19c is also provided at the boundary between the arrangement spaces 8 and 10 in the hermetic container 3 as shown in FIG. The left and right side plates 3L and 3R are bridged in the horizontal direction between the inner surface sides and bolted. As shown in FIG. 3, the protection plate 22 also has insertion holes 22 a to 22 c through which connection conductors 17 a to 17 c that electrically connect between the disconnecting switch 7 and the circuit breaker 9 are inserted. Here, the protection plate 22 is provided so as to be equal to or less than the gap defined for the object to be protected, and the material may be either an insulator or a conductive metal.

  In addition, as shown in FIGS. 4 and 5, the sealed container 3 has reinforcing concave portions 32 a to 32 d at four corner portions 31 a to 31 d at four corners as viewed from above. Here, as shown in an enlarged view in FIG. 5, the reinforcing concave portion 32 a is formed with bent portions 33 a and 33 b formed by bending the joint portion between the front plate portion 3 </ b> F and the left plate portion 3 </ b> L inwardly, respectively. A reinforcing piece 34 having an L-shaped cross section is fixed to the bent portion 33a by a fixing means such as spot welding so that an inverted U-shaped concave portion is formed by the reinforcing piece 34 and the bent portion 33b.

  Further, with respect to the reinforcing concave portion 32d diagonally to the reinforcing concave portion 32a, the joint portion between the back plate portion 3B and the right side plate portion 3R is bent inward to form the bent portions 35a and 35b. A reinforcing piece 36 having an L-shaped cross section is fixed to the bent portion 35a by a fixing means such as spot welding so that a U-shaped concave portion is formed by the reinforcing piece 36 and the bent portion 35b.

  Further, as shown in an enlarged view in FIG. 5, the reinforcing concave portion 32 b is formed by bending the right side plate portion 3 </ b> R to the inside at a right angle at the connection portion between the front plate portion 3 </ b> F and the right side plate portion 3 </ b> R, A bent portion 37b that reaches the extension portion 38 is formed by bending the bent portion 37a to the outside at a right angle and extending the front plate portion 3F to the outer surface of the right plate portion 3R. The U-shaped concave portions are formed by the bent portions 37a and 37b and the extension portion 38.

  Similarly, the reinforcing concave portion 32b and the diagonal reinforcing concave portion 32c are bent by bending the left side plate portion 3L inward at a right angle at the connecting portion between the back plate portion 3B and the left side plate portion 3L, as shown in an enlarged view in FIG. The bent portion 39a is formed, and the bent portion 39b is formed by bending the bent portion 39a outward at a right angle to reach the extended portion 40 extending the back plate portion 3B to the outer surface of the left plate portion 3L. By welding the tip of the portion 39 b to the extension portion 40, the bent portions 39 a and 39 b and the extension portion 40 form an inverted U-shaped recess.

Further, the sealed container 3 is sealed at a pressure that is the same as or slightly higher than the atmospheric pressure, and the inside is filled with a desiccant that adsorbs moisture, such as silica gel, and placed in a case so that the humidity is lower than the atmosphere. Is held to be.
Then, as shown in FIG. 6, a humidity sensor 41 is disposed in the sealed container 3, and this humidity sensor 41 is connected to a sealed abnormality monitoring device 43 disposed outside the sealed container 3 via a wiring 42. Yes. The sealing abnormality monitoring device 43 compares the humidity detection value Hd detected by the humidity sensor 41 with a preset threshold value Hth, and determines that the humidity detection value Hd is normal when the humidity detection value Hd is less than the threshold value Hth. When the threshold value Hth is exceeded, it is determined that the sealed state has collapsed, and an alarm signal SA is output to the alarm device 44.

  Thus, according to the said embodiment, since the protection plates 21 and 22 are arrange | positioned in the airtight container 3 in order to protect the charged buses 19a-19c, as shown by the prior art example mentioned above. The upper circuit breaker 5, the disconnect circuit 7 and the lower circuit breaker 9 are arranged in one sealed container 3 without providing three sealed containers that reliably prevent the charging unit of the switchgear from being exposed. Even if it does, it can protect the charging part of the switchgear with the protection plates 21 and 22, and can open the inspection opening / closing lids 2a to 2c to protect the charging part of the switchgear during the inspection work. .

Thus, since the upper circuit breaker 5, the disconnector 7 and the lower circuit breaker 9 are arranged in one sealed container 3, it is not necessary to provide three sealed containers as in the conventional example described above, Since only one sealed state monitoring device for monitoring the sealed state is required, the sealed container 3 can be simplified and the manufacturing cost can be reduced.
Further, since the reinforcing recesses 32a to 32d are formed at the four corners of the sealed container 3, the bent portions 33a, 33b and 35a, 35b forming the reinforcing recesses 32a and 32d and the L-shaped reinforcing piece 34 are formed. , 36, or the bent portions 37a, 37b and 39a, 39b and the extended portions 38 and 40 forming the reinforcing concave portions 32b and 32c are welded to increase the rigidity at the corner portions 31a to 31d. be able to.

  Further, since the L-shaped reinforcing pieces 34 and 36 and the extension portions 38 and 40 that are not directly related to the sealed portion of the sealed container 3 are provided in the reinforcing recesses 32a to 32d, the L-shaped reinforcing pieces 34, 36 and the extension portions 38 and 40 can be formed with frame fixing bolt holes, and this frame fixing screw hole can be formed outside the airtight portion. Therefore, it is not necessary to make a thick plate or weld a stud bolt, and it is possible to reduce the thickness.

Moreover, since the insulating property can be enhanced by sealing the dry air in the sealed container 3, the insulating performance is ensured only by maintaining the inside of the sealed container at a pressure slightly higher than the atmospheric pressure. The thickness of the sealed container 3 can be reduced, and the manufacturing cost can also be reduced in this respect.
Further, by sealing the dry air in the sealed container 3, the humidity is detected by the humidity sensor 41, and the humidity detection value Hd is compared with a preset humidity threshold value Hth to maintain the airtightness. It is possible to determine whether or not the airtightness has been lowered when Hd is equal to or higher than the humidity threshold Hth.

  In the above embodiment, the case where the humidity in the sealed container 3 is detected by the humidity sensor 41 when the sealed state is monitored has been described. However, the present invention is not limited to this. A dew point sensor may be provided in place of the sensor 41, and the sealed state may be determined by monitoring whether or not the dew point detected by the dew point sensor is equal to or greater than a preset dew point threshold value.

Moreover, in the said embodiment, although the case where the humidity sensor 41 was arrange | positioned in the airtight container 3 was demonstrated, it is not limited to this, The piping connected to the airtight container 3 is provided, and the other end of this piping Alternatively, a humidity measurement chamber may be formed, and the humidity sensor 41 may be disposed in the humidity measurement chamber.
Furthermore, although the said embodiment demonstrated the case where the reinforcement recessed parts 32a-32d formed in the corner part of the four corners of the airtight container 3 were formed in U shape, it is not limited to this, It shows in FIG. Thus, instead of the L-shaped bent portions 33a, 33b, 35a, 35b, 37a, 37b and 39a, 39b, an oblique bent portion 50 is formed, and V-shaped reinforcing concave portions 51a to 51d are formed. You may make it do.

  Moreover, in the said embodiment, although the case where reinforcement recessed part 32a-32d was each provided in each corner part 31a-31d of the airtight container 3 was demonstrated, it is not limited to this, In one or more corner parts A reinforcing concave portion may be provided, and further, a reinforcing concave portion may be formed in an intermediate portion between the corner portions 31a to 31d. As shown in FIGS. 5 and 7, in the sealed container 3 in which reinforcing recesses are formed at one or more corners of the four corners to increase rigidity, only one or more circuit breakers or disconnectors are installed in the sealed container 3. Even if it is feasible.

  DESCRIPTION OF SYMBOLS 1 ... Sealed switchboard, 2a-2c ... Opening / closing lid for inspection, 3 ... Sealed container, 3F ... Front plate part, 3R ... Back plate part, 3L ... Left side plate part, 3R ... Right side plate part, 5 ... Upper circuit breaker, 6 ... Arrangement space, 7 ... Disconnector, 8 ... Arrangement space, 9 ... Lower circuit breaker, 10 ... Arrangement space, 21, 22 ... Protection plate, 31a-31d ... Corner part, 32a-32d ... Reinforcing recess, 33a, 33b ... bent portion, 34 ... reinforcing piece, 35a, 35b ... bent portion, 36 ... reinforcing piece, 37a, 37b ... bent portion, 38 ... extended portion, 39a, 39b ... bent portion, 40 ... extended portion, DESCRIPTION OF SYMBOLS 41 ... Humidity sensor, 42 ... Wiring, 43 ... Sealed state monitoring apparatus, 44 ... Alarm apparatus, 50 ... Bending part, 51a-51d ... Reinforcement recessed part

Claims (4)

A sealed distribution board used for power distribution equipment,
A switchgear including at least a circuit breaker and a disconnecting switch is installed in the sealed container,
A protective plate that protects from a charging part when the sealed container is opened is disposed in the sealed container ,
The protective plate is disposed at a boundary position between the installation space in which the breaker is installed and the installation space in which the disconnector is installed, and has an insertion hole through which a connection conductor is inserted. switchboard. The closed container has the disconnector and bus in the middle arrangement space, the circuit breakers in the upper arrangement space and the lower arrangement space sandwiching the middle arrangement space, and the middle arrangement space and the upper arrangement space. 2. The hermetic switchboard according to claim 1 , wherein the protective plates are individually arranged between the arrangement space and the lower arrangement space . 3. The hermetic switchboard according to claim 1 , wherein the hermetic container is formed with a reinforcing concave portion formed of at least one of a U shape and a V shape at one or more corner portions of four corners.   Sealed state detection means for detecting at least one of humidity and dew point is disposed in the sealed container, and it is determined that there is a sealing abnormality when the detection value detected by the sealed state detection means is equal to or greater than a preset threshold value. The hermetic switchboard according to any one of claims 1 to 3, further comprising a hermetically sealed abnormality determining means.

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