JPH0652758A - Circuit breaker with resistor - Google Patents

Abstract

PURPOSE:To provide an excellent circuit breaker with a resistor equipped with a small size, simple, highly reliable resistor support structure which can support the resistor through securing sufficient mechanical strength, and can prevent the damage of the resistor and a support insulation with the change of dimension in a resistor axis direction. CONSTITUTION:A contact 1, a resistance contact 2, and a resistor 3 are contained in a closed vessel 7 filled with a insulating medium. Resistance units 21, 22 are connected mutually in series so as to constitute a resistor 3. A connection portion 23 between the resistance units 21, 22 is constituted so as to be absorbable of displacement amounts in axis directions of the respective resistance units 21, 22. One end 21b of the resistor 3 is fixed to the moving portion 1a side of the main contact 1, and the other end 22b of the resistor 3 is fixed to the fixed portion 1b side of the main contact 1. The connection portion 23 of the resistor 3 is fixed to the fixed portion 1b side of the main contact 1 via a support insulation 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker used in a substation of a high-voltage power system, and in particular, a resistance contact and a resistor are connected in series to connect this series circuit and a main contact. The present invention relates to a circuit breaker with a resistor connected in parallel.

[0002]

2. Description of the Related Art In a substation of a high voltage power system, a circuit breaker in which main contacts are housed in a tank filled with an insulating medium such as gas is used. In such a circuit breaker, in a gas circuit breaker for 500,000 volts, when an unloaded transmission line is turned on, a large overvoltage is generated. Therefore, a resistor may be used to suppress this. is there. In this case, it takes 10 ms to turn on the main contact.
After inserting the resistor to suppress the overvoltage,
The main contact is turned on. At this time, the energy consumed by the resistor is about several M Joules, and the volume, length, and weight of the resistor are not so large as compared with the main contact. Therefore, it is possible to obtain sufficient mechanical strength by disposing such a small and lightweight resistor in parallel with the main contact and fixing both ends of the resistor to the main contact with bolts or the like.

FIG. 2 is a diagram showing an example of a conventional circuit breaker with a two-point break resistor. The circuit breaker in this figure has two sets of main contacts 1
And two sets of resistance contacts 2 and two resistors 3 arranged in parallel with the main contact 1. Further, as an insulator, an end support insulating cylinder 5 that supports the end of the resistor 3 and a main insulating cylinder 6 that supports the main contact 1 are provided. Inside the end support insulating cylinder 5, the resistance contact 2 is provided. Are arranged. Each of these elements is housed in a gas tank 7 filled with an insulating gas. Further, in the figure, 8 is an insulating spacer for partitioning the inside and outside of the gas tank 7, and 9 is a connecting conductor for external drawing, which is supported by the insulating spacer 8. On the other hand, reference numeral 10 in the figure denotes a center piece for supporting two sets of main contacts 1 and electrically and mechanically connecting the main contacts 1 to each other. It is supported. The end supporting metal member 11 is supported on the center piece 10 via the end supporting insulating cylinder 5, and one end of the resistor 3 is fixed thereto by a bolt or the like, and the end supporting insulating cylinder is supported. 5 is electrically connected to the centerpiece 10 via the resistance contact 2 arranged in
It is mechanically connected. The other end of the resistor 3 is electrically and mechanically connected to the end supporting metal member 12 attached to the corresponding end of the main contact 1 by bolts or the like.

[0004]

By the way, in recent years, as the voltage of the power transmission system has been increased, an ultra-high voltage (UHV) power transmission system such as 1 million volts is also planned. In such a UHV gas circuit breaker, with the development of the breaking technology in recent years, it is attempted to cope with the two-point break main contact. In addition, not only at the time of turning on but also at the time of breaking, by inserting a resistor in parallel with the main contact, it is possible to reduce the rise rate of the re-elevation voltage after breaking that occurs in the main contact and to make the breaking easier. is there. Further, a resistor may be inserted in parallel with the main contact in order to suppress an overvoltage generated after interruption of a ground fault or the like. These resistors are 30-40ms after the completion of interruption.
Since it needs to be disconnected from the circuit, a resistor contact for the resistor is required. In addition, at the time of closing, similar to the circuit breaker for 500,000 volts, the main contact is closed after the preceding voltage is applied through the resistor to suppress overvoltage.

In the resistor used in such a UHV circuit breaker, the energy to be processed becomes extremely large. Specifically, it is 20 times as much as the resistor of the circuit breaker for 500,000 volts mentioned above. It is necessary to absorb a very large amount of energy up to 30 times. As a result, the volume, length and weight of the resistor are much larger than those of the circuit breaker for 500,000 volts. In particular, in order to obtain the required withstand voltage performance, it is necessary to stack disk-shaped resistor elements in multiple stages, and the length of the resistor becomes considerably longer than in the past, and the volume of the resistor is accordingly reduced. It gets bigger and heavier. With such an extremely long and heavy resistor, it is difficult to secure sufficient mechanical strength by fixing only both ends with bolts or the like as in the conventional case.

On the other hand, the UHV circuit breaker is larger in size than the circuit breaker for 500,000 volts, and
It is expected that the operating temperature range will be extremely wider than the operating temperature range of the circuit breaker for 500,000 volts.
In this case, if the axial dimension of the resistor changes due to thermal expansion when the temperature rises, a large stress is applied to the resistor and the supporting insulator that supports this resistor, causing the resistor to crack or the supporting insulator. May be damaged.

The present invention was proposed in order to solve the problems of the prior art as described above, and an object thereof is to support a resistor so as to ensure sufficient mechanical strength, and Excellent resistance suitable for UHV with a small, simple and highly reliable resistor support structure that can prevent damage to resistors and supporting insulators due to changes in the axial dimension of resistors. It is to provide a circuit breaker with a switch.

[0008]

A circuit breaker with resistance according to the present invention comprises a main contact having a movable part and a fixed part and a resistance contact having the movable part and a fixed part in a closed container filled with an insulating medium. , And a resistor are housed, the resistance contact and the resistor are connected in series, and in the circuit breaker with resistance in which the series circuit and the main contact are connected in parallel, the resistor is a series connection of two resistance units. And a connection portion between the two resistance units is configured to be able to absorb the displacement amount of each resistance unit in the axial direction, and one end of the resistor is fixed to the movable portion side of the main contact. The other end of the resistor is fixed to the fixed part side of the main contact, and the connection part of the resistor is fixed to the fixed part side of the main contact via a supporting insulator. Generally, both ends of the resistor are firmly fixed with bolts or the like.

[0009]

In the present invention constructed as described above, 2
2 resistor units are connected in series to form a resistor.
By configuring the connection between the individual resistance units to absorb the amount of axial displacement of each resistance unit, even if the resistor expands in the axial direction due to temperature rise, it absorbs the dimensional change. can do. Also, by supporting the resistor at the central portion (connection portion) in the axial direction by the supporting insulator attached to the fixed portion side of the main contact, the UH
Even a long and heavy resistor for V or the like can sufficiently secure the mechanical strength. In this case, if both ends of the resistor are firmly fixed with bolts, etc., a relatively small load is applied to the supporting insulator supporting the connection part of the resistor compared to both ends, so reliability is improved. Can be improved. Furthermore, since the resistor is supported from the fixed part side of the main contact,
No voltage is applied to this supporting insulation when the circuit breaker is open circuited.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a circuit breaker with a resistor according to the present invention will be specifically described below with reference to FIG.

FIG. 1 is a block diagram showing a typical embodiment of a circuit breaker with resistance according to the present invention. As shown in FIG. 1, the circuit breaker of this embodiment has two sets of main contacts 1 and two sets of main contacts 1.
A pair of resistance contacts 2 and 2 arranged in parallel with the main contact 1
It has a number of resistors 3. As an insulator, the resistor 3
A center support insulator 4 that supports the center of the resistor 3, an end support insulating cylinder 5 that supports the end of the resistor 3, and a main insulating cylinder 6 that supports the main contact 1. Further, in the figure, 7 is a gas tank (sealed container) filled with an insulating gas, 8 is an insulating spacer for partitioning the inside and outside of the gas tank 7, 9 is a connecting conductor with adjacent equipment, and 10 is two sets of main contacts. The center pieces 11 and 12 connecting between 1 are end supporting metal members for supporting both ends of the resistor 3, respectively.

That is, a center piece 10 is fixed on a main insulating cylinder 6 which is established from a grounded gas tank 7, and two sets of main contacts 1 are provided on both sides of the center piece 10 in a direction coaxial with the gas tank 7. Are arranged in a line, and are mechanically fixed to the center piece 8 and electrically connected. In other words, the two sets of main contacts 1 are electrically and mechanically connected in series via the center piece 10. In this case, the main contact 1 includes the main contact moving part 1a,
The main contact fixing part 1b and the inter-electrode supporting insulator 1c for mechanically connecting them are provided, and the main contact moving part 1a side is electrically and mechanically connected to the center piece 10, and The central support insulator 4 is provided on the main contact fixing portion 1c.
Is attached. An end supporting insulating cylinder 5 is attached on the center piece 10, and a resistance contact 2 is arranged coaxially in the internal space of the end supporting insulating cylinder 5.

The two resistors 3 are arranged above the two main contacts 1 in parallel with the main contacts 1. This resistor 3 connects two resistance units 21 and 22 to a connecting portion 2
3 connected in series. in this case,
The connecting portion 23 includes a central supporting metal member 24 that supports the abutting portions 21a and 22a of the resistance units 21 and 22. By combining fingers and springs between the central supporting metal member 24 and the resistance units 21 and 22, the abutting portions 21a and 22a of the resistance units 21 and 22 are connected to the central supporting metal member 24 by resistors. It is attached so as to be slidable in the axial direction of 3. The central supporting metal member 24 is insulated and supported by the central supporting insulator 4 with respect to the main contact fixing portion 1b.

One end of the resistor 3, that is, the end 21b of the one resistance unit 21 opposite to the abutting portion 21a is bolted to the end supporting metal member 11 supported by the end supporting insulating cylinder 5. The end supporting metal member 11 is electrically and mechanically connected. In this case, the end 21b of the resistance unit 21 is connected in series with the resistance contact 2 via the end supporting metal member 11, and further electrically connected to the main contact moving part 1a via the center piece 10. It is connected. The end 21b of the resistance unit 21 is supported by the center piece 10 via the end supporting metal member 11 and the end supporting insulating cylinder 5, and is mechanically fixed to the main contact moving part 1a.

On the other hand, the other end of the resistor 3, that is,
An end portion 21b of the other resistance unit 22 opposite to the butting portion 22a is fixed to the end supporting metal member 12 attached to the end of the main contact fixing portion 1b by a bolt. It is electrically and mechanically connected to the main contact fixing portion 1b via 12. A connection conductor 9 for external extraction is connected to the end portion support metal member 12, and the connection conductor 9 is supported by the insulating spacer 8.

In the present embodiment having the above-mentioned structure, even if the resistor 3 expands in the axial direction when the temperature rises, this expanded amount is generated by the abutting portions 21a and 22a of the resistance units 21 and 22. It is easily absorbed by sliding in the axial direction with respect to the central supporting metal member 24. Therefore, no extra stress is applied to the resistor 3, the central support insulator 4 and the end support insulating cylinder 5 that support the resistor 3, and the mechanical reliability can be improved. Also, with the assembly method that only tightens the bolts, it is necessary to assemble while adjusting the spacers for dimension adjustment.
As described above, when the resistor 3 is slidably mounted, since a considerable dimensional error can be absorbed, the dimensional adjustment at the time of assembly is very easy and the workability can be improved. Since the support point of the central support insulator 4 of the connecting portion 23 at the center of the resistor 3 is a fixed point, the dimensional change of the resistor 3 due to thermal expansion is caused by each resistance unit 21,
22 and therefore each butting portion 21
The sliding amount of a and 22a should be half the expansion amount of the entire resistor 3, the sliding structure can be made smaller by that much, and the design is easy.

In addition to the conventional support structure in which only both ends of the resistor 3 are fixed with bolts,
In the present embodiment, the central support insulator 4 attached to the main contact fixing portion 1b side is used for the central portion of the resistor 3 (connecting portion 2).
By supporting 3) as well, mechanical strength can be sufficiently ensured even in a long and heavy resistor 3 for UHV or the like. In this case, in this embodiment, both ends 2 of the resistor 3 are
Since 1b and 22b are firmly fixed with bolts, a relatively small load is applied to the central support insulator 4 that supports the connecting portion 23 of the resistor 3 as compared with both ends 21b and 22b of the resistor 3. Therefore, reliability can be improved. further,
Since the resistor 3 is supported by the central support insulator 4 attached to the main contact fixing portion 1b side, when the circuit breaker is in the open state, that is, both the main contact 1 and the resistance contact 2 are open. At times, no voltage is applied to the central supporting insulator 4, and in this respect, there is an advantage that deterioration of the central supporting insulator 4 can be prevented.

In addition, this embodiment is different from the resistor support structure of the conventional example (FIG. 2) in that the resistor 3 is divided into resistance units 21 and 22 and these are connected by the connecting portion 23. , And the central supporting insulator 4 is arranged in an empty space between the main contact 1 and the resistor 3, and the central supporting metal member 24 of the connecting portion 23 is supported by the central supporting insulator 4. As is apparent from FIG. 1, such a resistor support structure is extremely small and simple.

The present invention is not limited to the above-described embodiment. For example, the supporting insulator for supporting the center of the resistor is not limited to a single piece, and a plurality of pieces can be installed, and the shape thereof can be set. Also, a rod shape or a tubular shape can be appropriately selected.
Further, the specific structure of the connection portion between the resistance units of the resistor can be appropriately selected. Further, the specific configurations of the main contact and the resistance contact can be freely selected.

[0020]

As described above, according to the present invention,
Two resistors are connected in series to form a resistor,
The connection between the resistance units is configured to absorb the displacement in the axial direction.Furthermore, one end of the resistor is fixed to the movable part side of the main contact, and the other end of the resistor is fixed to the fixed part side of the main contact. By fixing and fixing the connection part of the resistor to the fixed part side of the main contact via the support insulator, the resistor can be supported while ensuring sufficient mechanical strength, and An excellent circuit breaker with resistance, suitable for UHV, equipped with a small, simple and highly reliable resistor support structure that can prevent damage to resistors and supporting insulators due to changes in axial dimension. Can be provided.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a typical embodiment of a circuit breaker with a resistor according to the present invention.

FIG. 2 is a configuration diagram showing an example of a conventional circuit breaker with a resistance.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Main contact 1a ... Main contact movable part 1b ... Main contact fixed part 1c ... Inter-electrode support insulator 2 ... Resistive contact 3 ... Resistor 4 ... Central support insulator 5 ... End support insulating cylinder 6 ... Main insulating cylinder 7 ... Gas tank 8 ... Insulating spacer 9 ... Connection conductor 10 ... Center piece 11, 12 ... End supporting metal members 21, 22 ... Resistor units 21a, 22a ... Butt portions 21b, 22b ... End 23 ... Connecting portion 24 ... Central supporting metal Element

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kuri Ikeda 2-1, Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Stock company Toshiba Hamakawasaki Plant (72) Hiroaki Toda 2nd, Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa No. 1 stock company Toshiba Hamakawasaki factory

Claims (1)

[Claims] 1. A closed container filled with an insulating medium,
A main contact having a movable part and a fixed part, a resistance contact having a movable part and a fixed part, and a resistor are housed, the resistance contact and the resistor are connected in series, and the series circuit and the main contact are connected in parallel. In the connected circuit breaker with a resistor, the resistor is configured by connecting two resistance units in series, and the connection portion between the two resistance units can absorb the displacement amount of each resistance unit in the axial direction. The one end of the resistor is fixed to the movable part side of the main contact, the other end of the resistor is fixed to the fixed part side of the main contact, and the connecting part of the resistor is a supporting insulator. A circuit breaker with a resistor, which is fixed to the fixed portion side of the main contact through the breaker.