JP2003331700A - Power switching device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low cost and high performance power switching device which is assembled easily. <P>SOLUTION: The power switching device has a plurality of vacuum circuit breaker units which are constituted by combining vacuum switches, operating means and insulator operating rods with insulator supporters respectively; electrically conductive connecting members which connect a plurality of the vacuum circuit breaker units electrically in series; and a metal case which holds and contains the vacuum circuit breaker units which are connected in series. It is possible to insulate the operating means from the metal case by filling the inside of the metal case with insulating oil. Power for the operating means is supplied from a transformer which is disposed on an electrically conductive member on a side of the movable contacts of the vacuum switches. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power switchgear, and more particularly to a high voltage power switchgear using a vacuum switch.

[0002]

2. Description of the Related Art The vacuum withstand voltage tends to saturate gradually as the distance between electrodes increases, and there is a limit to increasing the voltage of a vacuum switch. On the other hand, the dependency of the withstand voltage of SF _{6 on} the distance between the electrodes has a weaker tendency of saturation as compared with the vacuum withstand voltage, and the withstand voltage can be improved by increasing the gas pressure. Therefore, the vacuum circuit breaker has only been put into practical use at a voltage of 100 kV or less, and a gas circuit breaker has been used exclusively for high voltage switching of 100 kV or more.

The power switchgear disclosed in Japanese Unexamined Patent Publication No. 50-143079 or Japanese Unexamined Patent Publication No. 50-53869 has a vacuum switch arranged in an atmosphere of insulating gas or insulating oil. Although the edge surface withstand voltage is improved, it is difficult to cut off a voltage of 100 kV or more with a single vacuum switch without connecting a plurality of vacuum switches in series.

The vacuum switchgear disclosed in Japanese Unexamined Patent Publication No. 51-48179 is one in which a capacitor is integrally molded although it is not placed in insulating oil, and a plurality of vacuum switches are connected in series. However, the specific configuration of the series connection is not disclosed.

The vacuum circuit breaker disclosed in Japanese Patent Laid-Open No. 51-45285 has at least two vacuum circuit breakers connected in series and arranged in a metal case containing SF ₆ gas. It can be operated.

[0006]

The conventional switchgear described above has the following problems. That is, in order to increase the voltage of the vacuum circuit breaker, a method of connecting a plurality of vacuum switches in series has been proposed. Since it is necessary to dispose an insulating operation rod that can withstand the test voltage of the container, the movable weight increases as the number of vacuum switches increases, and the load at the time of high-speed operation of the operation mechanism increases. Further, since it is necessary to apply a proper contact pressure to all the vacuum switches when the electrodes are closed, the load on the operating mechanism increases as the number of vacuum switches increases. Furthermore, it is necessary to insulate and support the charging parts such as vacuum switches and conductors from the metal casing of the circuit breaker, which is at ground potential, and to connect the vacuum switches and the operating mechanism. There was a problem that the structure became complicated.

Therefore, an object of the present invention is to solve the problems of the conventional power switchgear described above. Another object of the present invention is to provide a power switchgear in which a plurality of vacuum switches are connected in series, the movable weight does not increase, the load on the operating mechanism is small, and the structure is simple. A high-voltage vacuum circuit breaker that is easy to assemble and low cost can be realized.

[0008]

According to the present invention, the means for solving the above problems are as follows. (1) Vacuum switch, operating mechanism for opening and closing the vacuum switch, insulating operating rod for transmitting operating force of the operating mechanism to the vacuum switch, and the vacuum switch, operating mechanism and insulating operating rod integrally A plurality of vacuum circuit breaker units each having an insulating support that is supported as a unit, a connecting conductor electrically connecting the plurality of vacuum circuit breaker units in series with each other, and accommodating and supporting the vacuum circuit breaker units connected in series. A power switchgear having a metal housing.

(2) A vacuum switch having a pair of fixed contacts and a movable contact in a vacuum container, an operating mechanism for driving the movable contact, and a metal operating rod for transmitting the operating force of the operating mechanism to the movable contact. , And a plurality of vacuum circuit breaker units having an insulating support for supporting the vacuum switch together with the operating mechanism and the insulating operation rod as an integral unit, and the plurality of vacuum circuit breaker units are electrically connected in series. A switchgear for electric power provided with a connecting conductor, a metal housing for housing and supporting the plurality of vacuum circuit breaker units, and an insulating device for electrically insulating the operating mechanism from the metal housing.

(3) The energy of the operating mechanism is supplied from a current transformer installed in the conductor on the movable contact side of the vacuum switch, and the cut-off closing command is transmitted to the operating mechanism electrically from the operation panel without contact. You may want to be told.

(4) The conductor surface connecting the units of the vacuum switch may be covered with a solid insulator.

(5) The solid insulator for supporting the vacuum switch may be cast integrally with the vacuum switch.

(6) The inside of the metal housing may be filled with insulating oil.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. FIG. 1 is a schematic sectional view showing an embodiment of a power switchgear of the present invention. The power switchgear includes a metal housing 1 which is a hermetically sealed container that houses an insulating medium such as insulating oil. In the illustrated example, four vacuum circuit breaker units 2 are arranged in the metal housing 1, and the vacuum circuit breaker units 2 are connected to each other in series by connecting conductors 3 and 4. Both ends of the vacuum circuit breaker units 2 connected in series are connected to an external connection bushing 6 via terminal conductors 5 so that they can be connected to an external circuit (not shown).

Each vacuum circuit breaker unit 2 includes a vacuum switch 8 having a pair of fixed contacts and movable contacts (not shown) in a vacuum container 7. The fixed contact of the vacuum switch 8 is fixed to the inner end of the fixed-side conductor 9 that penetrates the vacuum container 7 and extends to the outside, and the movable contact moves the vacuum container 7 via a bellows (not shown) or the like. It is fixed to the inner end of the movable-side conductor 10 extending through the airtightly. Of the vacuum circuit breaker units 2 connected in series by the connecting conductors 3 and 4, the fixed side conductor 9 of the outermost vacuum circuit breaker unit 2 has a terminal conductor 5 for connecting to an external circuit (not shown). Are connected, and the connecting conductor 3 is connected between the fixed-side conductors 9 of the vacuum circuit breaker unit 2 on the inside.

A shunt portion 11 electrically connected to the movable conductor 10 of the vacuum switch 8 by a flexible conductor or a sliding conductor so as not to interfere with the opening / closing operation of the movable contact.
Is provided, and the connection conductor 4 is provided between the shunt portions 11.
Connected by. In this way, all vacuum circuit breaker units 2 are electrically connected in series with each other. When the fixed-side conductors 9 of the vacuum circuit breaker unit 2 are connected and the movable-side conductors 10 of the vacuum circuit breaker unit 2 are connected, the conductor arrangement for connecting the vacuum circuit breaker units 2 can be simplified. One end of the insulating operation rod 12 is connected to the outer end of the movable conductor 10, and the operation mechanism 13 is connected to the other end.
The movable contact can be opened and closed by the operating mechanism 13 via the insulating operating rod 12. Each operating mechanism 13 is provided with an insulating support 14 which is a solid insulator such as an epoxy resin, and the vacuum switch 8, fixed side conductor 9 and movable side conductor 1 which are connected and connected as described above.
0, the shunt portion 11, the connecting conductor 4, and the insulating operating rod 12 are supported together with the operating mechanism 13 as an integral unit so that the vacuum circuit breaker unit 2 has an independent structure. The vacuum circuit breaker unit 2 is configured to function as a circuit breaker by itself.

The power switchgear further comprises a metal housing 1 which encloses and supports the vacuum circuit breaker units 2 thus constructed and connected in series. The metal casing 1 is grounded, and an insulating medium such as insulating oil, SF6 gas, compressed air, compressed nitrogen gas is sealed inside. An operation panel 17 connected to each operation mechanism 13 by a signal line 16 is provided outside the metal housing 1 so that the operation of the vacuum circuit breaker unit 2 can be controlled.

FIG. 2 shows the relationship between the operation mechanism 13 and the operation panel 17 shown in FIG. 1. As is clear from the figure, the operation mechanism 13 is an operation mechanism housing 18 for electrostatic shield.
And an actuator 19 provided in the operation mechanism housing 18 and connected to the insulating operation rod 12. The actuator 19 is connected to the operation panel 1 by the signal line 16.
7, a magnetic actuator type that is constructed by combining an electromagnet and a permanent magnet and operates by electromagnetic force, and a motor winding spring type that operates by winding a spring with a motor to store energy. Etc.
It is recommended to use it properly according to the voltage class of the vacuum switch.

The number of vacuum circuit breaker units 2 connected in series may be changed depending on the breaking performance of the vacuum switch 8 and the required breaking performance of the target power switchgear. For example, 7
3 when using 4 vacuum switches 8 of 7-84kV class
A switchgear for electric power of 00 kV can be configured, and a switchgear for electric power of 500 kV can be obtained by using six switches.

When the power switchgear is closed, its operating voltage or test voltage is applied to the vacuum switch 8. Therefore, the insulating support 14 and the insulating operating rod 12 that support the vacuum switch 8 are required to have insulating performance that can withstand this operating voltage or test voltage. Further, when the power switchgear is opened, the voltage shared by the vacuum switch 8, that is, a voltage obtained by dividing the operating voltage or the test voltage by the number of the vacuum switches 8 is applied between the terminals of the vacuum switch 8.
Insulation performance that can withstand this voltage is required between the terminals. When considering such insulation, it is necessary to secure insulation performance at the insulation medium between the charged parts and at the interface between the solid insulation and the fluid insulation medium, in addition to the insulation performance of the solid insulation itself. Becomes Insulating oil, SF6 gas, compressed air, compressed nitrogen gas, or the like can be used as the insulating medium filled and sealed in the metal housing 1. Since these characteristics are well known, the description thereof is omitted here.

In the power switchgear configured as described above, the shutoff command from the operation panel 17 is supplied through the signal line 16 to simultaneously actuate the operation mechanisms 13 in the metal casing 1 to cause the vacuum circuit breakers to operate. The vacuum switch 8 of the unit 2 is opened simultaneously. Similarly, when a closing command is issued, the operating mechanism 13 simultaneously operates to simultaneously close the vacuum switches 8 of the vacuum circuit breaker units 2. The signal line 16 can be an optical cable or an electric cable, but instead of the signal line 16, a wireless signal can be transmitted.

Since the operating mechanism 13 is independently provided in each vacuum circuit breaker unit 2, each vacuum circuit breaker unit 2 can be operated individually. Therefore, by providing a vacuum circuit breaker unit, which is not only for disconnection but also for disconnection, in series with the other vacuum circuit breaker unit 2 and provided in the metal casing 1, the switching function for power and the disconnection function are matched. Can be held. Further, since it is sufficient to apply the contact pressure to each of the vacuum switches separately when the electrodes are closed, the burden on the operating mechanism does not increase even when the number of vacuum switches is large.

Embodiment 2. FIG. 3 shows another embodiment of the power switchgear of the present invention. The structure of this power switchgear is the same as that of the power switchgear shown in FIG. 1 as a whole, except for the structure of the insulating support 21 of the vacuum circuit breaker unit 20. That is, each vacuum circuit breaker unit 20
In, the insulating support 21 includes a main body 22 that supports the vacuum switch 8 and the operating mechanism 13 at a predetermined interval. The insulating support 21 is also provided with a switch support portion 23 which is integrally cast around the main body 22, the vacuum switch 8, the fixed side conductor 9 and the connection conductor 3 or the terminal conductor 5 to insulate and support them. Further, the connection conductor support portion 2 is integrally cast around the outer ends of the connection conductors 4 for connecting the shunt portions 11 to insulate and support the connection conductor 4.
4 is also provided. By sandwiching an elastomer material such as silicon rubber or ethylene propylene rubber between the connecting conductor supporting portions 24 of the adjacent vacuum circuit breaker units 20, it is possible to secure the insulation reliability of the solid insulator connecting interface. Other configurations are the same as those of the embodiment shown in FIGS. 1 and 2.

Since the insulation performance of the insulating support 21 which is a solid insulator is superior to that of insulating gas or insulating oil, the high voltage charging parts such as the vacuum switch 8 and the connecting conductors 3 and 4 are covered with the solid insulator. As a result, the charging section is sufficiently insulated, the performance is further improved, and a compact and highly reliable power switchgear can be supplied.

Embodiment 3. 4 and 5 show another embodiment of the power switchgear of the present invention. The structure of this power switchgear is similar to that of the power switchgear shown in FIG. 3 as a whole, except that a current transformer 25 and an insulating device 26 are provided, and the insulating operating rod 12 is removed. The other configurations are the same.

That is, in this power switchgear, the current transformer 25 is provided on the integrally cast connection conductor support portion 24 that insulates and supports the connection conductor 4 that connects between the shunt portions 11, and this transformer 25 is provided. As shown in FIG. 5, the sink 25 is connected to the actuator 19 via a control circuit 28 of the operating mechanism 13 by a wire 27 so as to act as a power source for the actuator 19. Energy from the current transformer 25 is always stored in a battery (not shown) provided in the control circuit 28. By disposing the current transformer 25 at this position, the connection conductor 4, the operating mechanism 13, and the current transformer 25 all have the same potential, so that the insulating structure can be simplified.

Further, in the illustrated example, signals are transmitted and received between the operation mechanism 13 and the operation panel 17 by wireless communication via an interface 29 provided in the operation mechanism 13, and the operation mechanism 13 is operated. The shutoff closing command can be communicated electrically from the operation panel 17 in a non-contact manner. Optical communication using an optical fiber or the like can be used instead of wireless communication. In this way, the energy for operating the operating mechanism 13 is supplied from the current transformer 25 installed in the conductor on the movable contact side of the vacuum switch 8, that is, the connecting conductor 4, and the command for shutting on is transmitted to the operating mechanism 13. The operation panel 17 is designed to be electrically non-contacting.

The insulating device 26 of the power switchgear is a support base that supports the operating mechanism 13 in an electrically insulated state with respect to the metal housing 1. In the illustrated example, the shunt portion of the movable conductor 10 is provided. Connection conductor 4 on the movable contact side connected between 11
Two vacuum circuit breaker units 2 connected by a pair form a pair, and two such pairs are formed. The two vacuum circuit breaker units 2 are a single insulating device common to each pair. It is insulated and supported by 26. Since the operating mechanism 13 is electrically non-grounded in this way, it is not necessary to provide the insulating operating rod 12 between the vacuum switch 8 and the operating mechanism 13, and the movable conductor 10 provided with the shunt portion 11 is eliminated. Can be directly used as a metal operating rod and directly connected to the operating mechanism 13. By omitting the insulating operation rod 12 as described above, the total weight of the movable portion can be significantly reduced, the operation speed can be increased, and the operation mechanism 13 can be downsized.

As described above, by constructing the operating rod between the vacuum switch and the operating mechanism from a metal material and eliminating the insulating operating rod, the weight of the movable portion can be reduced and the load on the operating mechanism can be reduced. be able to. In addition, the energy of the operating mechanism is supplied from the current transformer installed on the conductor on the movable contact side of the vacuum switch, and the transmission of the shut-off command to the operating mechanism is transmitted from the operation panel electrically without contact. Since the mechanism, the current transformer, and the busbar can be made to have the same electric potential and insulation is facilitated, power can be easily supplied from the current transformer to the operating mechanism.

[0030]

As described above, the effects of the power switchgear according to the present invention are as follows. (1) The power switchgear of the present invention includes a vacuum switch, an operation mechanism for opening and closing the vacuum switch, an insulating operation rod for transmitting the operation force of the operation mechanism to the vacuum switch, the vacuum switch, and the operation. A plurality of vacuum circuit breaker units each including a mechanism and an insulating support body that integrally supports the insulating operation rod as a unit, and a connection conductor that electrically connects the plurality of vacuum circuit breaker units to each other in series are connected in series. Since it has a metal housing that accommodates and supports the above vacuum circuit breaker unit, a high voltage vacuum circuit breaker that is easy to assemble and low in cost can be realized when configuring a high voltage vacuum circuit breaker.

(2) Further, the power switchgear of the present invention is
True with a pair of fixed and moving contacts in a vacuum vessel
Empty switch, operating mechanism for driving movable contact, above
Metal operation that transmits the operating force of the operating mechanism to the movable contact
Attach the rod and the vacuum switch to the operating mechanism and
And an integral unit with the above metal operating rod
Multiple vacuum circuit breaker units with insulated supports to support
And the plurality of vacuum circuit breaker units electrically connected to each other.
The connecting conductors connected in series and the above vacuum breaker units
The metal housing that holds and supports the
It has an insulation device that electrically insulates it from the housing.
The operating rod between the vacuum switch and the operating mechanism is a metal
Due to the elimination of the insulated operating rod made of material
The weight of the moving parts can be reduced, and the load on the operating mechanism is small.
You can do it.

(3) Further, the energy of the operating mechanism is supplied from the current transformer installed in the conductor on the movable contact side of the vacuum switch, and the transmission of the interruption input command to the operating mechanism is electrically non-contact from the operation panel. Since the operation mechanism, the current transformer, and the busbar have the same potential and insulation is facilitated, power supply from the current transformer to the operation mechanism is facilitated.

(4) Since the surface of the conductor connecting the units of the vacuum switch is covered with the solid insulator, the charge exposed portion is covered with the solid insulator having excellent insulation characteristics, and the insulation performance can be improved.

(5) Since the solid insulator supporting the vacuum switch is integrally cast with the vacuum switch, the exposed portion of the charge is covered with the solid insulator having excellent insulation characteristics, and the insulation performance can be improved. .

(6) Since the metal casing is filled with insulating oil, the cooling performance can be improved by circulating the insulating oil, and a large current can be applied to the circuit breaker.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a power switchgear of the present invention.

FIG. 2 is a block diagram showing an operating mechanism of the power switchgear of the present invention.

FIG. 3 is a schematic sectional view showing another embodiment of the power switchgear of the present invention.

FIG. 4 is a schematic cross-sectional view showing still another embodiment of the power switchgear of the present invention.

5 is a block diagram showing an operating mechanism of the power switchgear of FIG. 4. FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 metal casing, 2 vacuum circuit breaker unit, 3, 4 connection conductor, 8 vacuum switch, 10 metal operating rod (movable side conductor), 12 insulating operating rod, 13 operating mechanism,
14, 21 Insulation support, 16 Control panel, 25 Current transformer, 26 Insulator.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kenichi Koyama             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. (72) Inventor Shinji Sato             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. F-term (reference) 5G026 RA01 RA06 RB04

Claims (6)

[Claims] 1. A vacuum switch, an operating mechanism for opening and closing the vacuum switch, an insulating operating rod for transmitting an operating force of the operating mechanism to the vacuum switch, and the vacuum switch, the operating mechanism and the insulating operating rod. A plurality of vacuum circuit breaker units provided with an insulating support that are integrally supported as a unit, a connection conductor that electrically connects the plurality of vacuum circuit breaker units in series with each other, and the vacuum circuit breaker units connected in series A switchgear for electric power having a supporting metal casing. 2. A vacuum switch having a pair of fixed contacts and a movable contact in a vacuum container, an operation mechanism for driving the movable contact, a metal operation rod for transmitting an operation force of the operation mechanism to the movable contact, And the vacuum switch
A plurality of vacuum circuit breaker units provided with an insulating support that supports the operation mechanism and the metal operation rod as an integral unit, a connecting conductor electrically connecting the plurality of vacuum circuit breaker units to each other in series, A switchgear for electric power provided with a metal housing that accommodates and supports a plurality of vacuum circuit breaker units, and an insulating device that electrically insulates the operating mechanism from the metal housing. 3. The power switchgear according to claim 2, wherein the energy of the operating mechanism is supplied from a current transformer installed in a conductor on the movable contact side of the vacuum switch, and a command for shutting on is transmitted to the operating mechanism. A switchgear for electric power, which is electrically contactless from an operation panel. 4. The power switchgear according to claim 1, wherein the conductor surface connecting the units of the vacuum switch is covered with a solid insulator. . 5. The power switchgear according to claim 1, wherein the solid insulator supporting the vacuum switch is integrally cast with the vacuum switch. apparatus. 6. The power switchgear according to claim 1, wherein the metal casing is filled with insulating oil.