JP3233460B2 - Circuit breaker with resistance - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker for use in a substation of a high-voltage power system, and more particularly to a circuit breaker for connecting a resistor contact and a resistor in series. 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 having a main contact housed in a tank filled with an insulating medium such as gas is used. Among such circuit breakers, in a 500,000 volt gas circuit breaker, when a no-load transmission line is inserted, a large overvoltage is generated, and 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 ahead of time and suppressing the overvoltage,
The main contacts are turned on. At this time, the energy consumed by the resistor is about several M joules, and none of the volume, length, and weight of the resistor is much larger than that of the main contact. Therefore, such a small and lightweight resistor can be provided with sufficient mechanical strength by being arranged in parallel with the main contact and fixing both ends to the main contact with bolts or the like.

FIG. 2 is a diagram showing an example of a conventional breaker with two-point 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 tube 5 for supporting an end of the resistor 3 and a main insulating tube 6 for supporting the main contact 1 are provided. Is arranged. These components are stored in a tank 7 filled with an insulating gas. Further, in the figure, reference numeral 8 denotes an insulating spacer for dividing the inside and the outside of the tank 7 into gases, and 9 denotes 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 the two sets of main contacts 1 and electrically and mechanically connecting the main contacts 1 to each other. Supported. And on this centerpiece 10,
An end support metal member 11 is supported via an end support insulating cylinder 5, and one end of a resistor 3 is fixed to the end support metal member 11 by a bolt or the like, and a resistance contact 2 disposed in the end support insulating cylinder 5. Through the center piece 10 electrically and mechanically. The other end of the resistor 3 is fixed to an end support metal member 12 attached to a corresponding end of the main contact 1 by a bolt or the like, and is electrically and mechanically connected.

[0004]

By the way, in recent years, the power transmission system has been increased in voltage, and a transmission system of an ultra-high voltage (UHV) such as one million volts has been planned. In such a UHV gas circuit breaker, with the recent development of the circuit breaker technology, a two-point main contact has been used. In addition, not only at the time of closing but also at the time of breaking, a method may be adopted to ease the breaking by reducing the rate of increase of the re-motive voltage after breaking at the main contact by inserting a resistor in parallel with the main contact. is there. Further, a resistor may be inserted in parallel with the main contact in order to suppress an overvoltage generated after interruption such as a ground fault. These resistors are 30-40 m after the shutoff is complete.
Since s needs to be disconnected from the circuit, a resistor contact for the resistor is required. In addition, at the time of closing, as in the case of the 500,000 volt circuit breaker, the over-voltage is suppressed by preceding closing via a resistor, and then the main contact is closed.

[0005] In the resistor used for such a UHV circuit breaker, the energy to be processed is extremely large. It needs to absorb ~ 30 times as much energy. As a result, the volume, length and weight of the resistor are much larger than those of the 500,000 volt circuit breaker resistor. 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 is considerably longer than before, and the volume of the resistor is accordingly increased. It gets bigger and heavier. In the case of an extremely long and heavy resistor as described above, it is difficult to secure sufficient mechanical strength only by fixing both ends of the resistor with bolts or the like.

[0006] On the other hand, the UHV circuit breaker is larger than the 500,000 volt circuit breaker in addition to the overall size of the equipment.
It is expected that the operating temperature range will be much wider than the operating temperature range of a 500,000 volt circuit breaker.
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 the resistor, and the resistor breaks or the supporting insulating material is damaged. May be damaged.

[0007] The present invention has been proposed to solve the above-mentioned problems of the prior art, and an object of the present invention is to support a resistor so as to ensure sufficient mechanical strength, and An excellent resistor suitable for UHV, equipped with a compact, simple and highly reliable resistor support structure that can prevent damage to the resistor and supporting insulator due to changes in the axial dimension of the resistor. To provide a circuit breaker.

[0008]

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

[0009]

According to the present invention having the above-described structure, 2
Resistors are connected in series to form a resistor,
By configuring the connection between the resistance units so that the amount of displacement of each resistance unit in the axial direction can be absorbed, even if the resistor expands in the axial direction due to temperature rise, it absorbs the dimensional change. can do. Further, by supporting the resistor at a central portion (connection portion) in the axial direction of the resistor by a supporting insulator attached to the fixed portion side of the main contact, the UH
Even with a long and heavy resistor such as for V, sufficient mechanical strength can be secured. 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 that supports the connection part of the resistor compared to both ends, so reliability is reduced. Can be improved. Furthermore, since the resistor is supported from the fixed part side of the main contact,
When the circuit breaker is open, no voltage is applied to this support insulator.

[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 a resistor according to the present invention. As shown in FIG. 1, the circuit breaker according to the present embodiment has two sets of main contacts 1 and two sets of main contacts 1.
A set of resistive contacts 2 and 2 arranged parallel to main contact 1
It has resistors 3. As an insulator, a resistor 3
A central supporting insulator 4 supporting the center of the resistor 3, an end supporting insulating cylinder 5 supporting an end of the resistor 3, and a main insulating cylinder 6 supporting the main contact 1 are provided. Further, in the figure, reference numeral 7 denotes a tank (sealed container) filled with an insulating gas, 8 denotes an insulating spacer for dividing the inside and outside of the tank 7 into gas, 9 denotes connection conductors to adjacent devices, and 10 denotes two sets of main contacts. Center pieces 11 and 12 for connecting between the two 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 established from a grounded tank 7, and two sets of main contacts 1 are provided on both sides of the center piece 10 in a coaxial direction with the tank 7. , And are mechanically fixed to the center piece 8 and electrically connected thereto. 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 a main contact movable portion 1a, a main contact fixed portion 1b, and a gap supporting insulator 1c for mechanically connecting the main contact movable portion 1a and the main contact movable portion 1a.
In addition to being electrically and mechanically connected to the center piece 10, a center support insulator 4 is mounted on the main contact fixing portion 1b. An end support insulating cylinder 5 is mounted on the center piece 10.
The resistance contact 2 is arranged in the internal space of the.

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

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

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

In this embodiment having the above-described configuration, even if the resistor 3 expands in the axial direction when the temperature rises, the amount of the expansion is determined by the butting 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, respectively. Therefore, no extra stress is applied to the resistor 3, the center supporting insulator 4 and the end supporting insulating cylinder 5 that support the resistor 3, and the mechanical reliability can be improved. In the assembly method using only bolt tightening, it is necessary to perform assembly while adjusting the size adjustment spacer.
As described above, when the resistor 3 is slidably mounted, a considerable dimensional error can be absorbed, so that dimensional adjustment at the time of assembly is very easy, and there is an advantage that workability can be improved. Since the support point of the connection portion 23 at the center of the resistor 3 by the central supporting insulator 4 is a fixed point, the dimensional change of the resistor 3 due to thermal expansion is reduced by the resistance units 21 and
22 so that the respective butting portions 21
The sliding amount of a and 22a may be half of the expansion of the entire resistor 3, so that the sliding structure can be reduced in size and the design is easy.

Further, in addition to the conventional support structure in which only both ends of the resistor 3 are fixed with bolts or the like,
In the present embodiment, the central portion of the resistor 3 (the connecting portion 2)
By supporting 3), sufficient mechanical strength can be ensured even for 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
1b and 22b are firmly fixed with bolts, so that a relatively small load is applied to the center support insulator 4 supporting 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 supporting insulator 4 attached to the main contact fixing portion 1b, when the circuit breaker is in an open state, that is, both the main contact 1 and the resistance contact 2 are open. Occasionally, no voltage is applied to the central support insulator 4, and in this regard, there is an advantage that deterioration of the central support insulator 4 can be prevented.

Furthermore, the present embodiment is different from the conventional resistor supporting structure (FIG. 2) in that the resistor 3 is divided into resistor units 21 and 22 and these are connected by a connecting portion 23. And the central support insulator 4 is disposed in an empty space between the main contact 1 and the resistor 3, and the central support insulator 4 supports the central support metal member 24 of the connection portion 23. As is clear from FIG. 1, such a resistor support structure is extremely small and simple.

The present invention is not limited to the above embodiment. For example, the number of supporting insulators supporting the center of the resistor is not limited to one, and a plurality of insulators may be provided. Also, a rod shape, a cylindrical shape, or the like can be appropriately selected.
Further, the specific structure of the connection between the resistance units of the resistor can be appropriately selected. Further, specific configurations of the main contact and the resistance contact can be freely selected.

[0020]

As described above, in the present invention,
A resistor is constructed by connecting two resistor units in series,
The connection between the resistance units is configured to be able to absorb the amount of displacement in the axial direction, and one end of the resistor is fixed to the movable portion of the main contact, and the other end of the resistor is fixed to the fixed portion of the main contact. By fixing and connecting the resistor connection part to the fixed part side of the main contact via a supporting insulator, it is possible to support the resistor while ensuring sufficient mechanical strength, and 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. Can be provided.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a representative 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 resistor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Main contact 1a ... Main contact movable part 1b ... Main contact fixed part 1c ... Inter-layer support insulator 2: Resistive contact 3 ... Resistor 4: Central support insulator 5 ... End support insulation cylinder 6 ... Main insulation cylinder 7 ... Tank 8 ... Insulating spacer 9 ... Connection conductor 10 ... Center piece 11,12 ... End support metal member 21,22 ... Resistor unit 21a, 22a ... But 21b, 22b ... End 23 ... Connection 24 ... Center support metal Element

──────────────────────────────────────────────────続 き Continuing on the front page (72) Kuri Ikeda 2-1 Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Inside the Hamakawasaki Plant, Toshiba Corporation (72) Inventor Hiroaki Toda 2-1 Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa No. In the Hamakawasaki Plant of Toshiba Corporation (56) References JP-A-51-103268 (JP, A) JP-A-3-254026 (JP, A) JP-A-58-42118 (JP, A) 73543 (JP, U) Fully open 1986-189947 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01H 33/16

Claims (1)

(57) [Claims] 1. A sealed 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 this 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 resistor units in series, and a connection portion between the two resistor units can absorb the displacement amount of each resistor unit in the axial direction. Wherein 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 portion side of the main contact, and the connection portion of the resistor forms a supporting insulator. A circuit breaker with a resistance, which is fixed to a fixed portion side of the main contact via a contact.