JPH04137418A - Making resistance built-in puffer type gas-blast circuit breaker - Google Patents

Abstract

PURPOSE:To reduce an installation space by arranging making resistance elements along the approximately same periphery with the axis of a main contact as the center on the back side of the fixed electrode supporting structure portion of the main contact in a decentralized fashion in parallel to the axial line of the main contact to support both ends of the resistance elements with insulation from the fixed electrode supporting structure portion. CONSTITUTION:A making resistance element 3a is supported to the back of the fixed electrode supporting structure portion 21 via insulating rods 31, 32 with insulation from the fixed electrode supporting structure portion 21. The making resistance element 3a is split into four along the approximately same periphery with the axis of an arc extinguish chamber 2 as the center on the back side of the fixed electrode supporting structure portion 21 in parallel to the axial line of the main contact portion. In this way, with the resistance elements 3a split-arranged along the approximately same periphery with the axis of the main contact as the center on the back side of the fixed electrode supporting structure portion 21 in parallel to the axial line of the main contact portion, each resistance element 3a can be reduced in length and arranged without the enlarged inner dia. of a tank in an extremely compact configuration.

Description

DETAILED DESCRIPTION OF THE INVENTION [Objective of the Invention (Industrial Field of Application) The present invention relates to a puffer type gas circuit breaker with a closing resistor in which the entire device is downsized.

(Prior Art) As the capacity of power transmission systems increases, the breaking capacity of circuit breakers used in substations and switchyards increases, and high reliability is required. In order to improve the reliability of circuit breakers, it is important to reduce the number of parts and simplify the structure. Therefore, efforts are being made to reduce the number of breaking points of circuit breakers. For example, in the 550 KV system, a two-point buffer type gas circuit breaker with a breaking current of 50 KA is currently in practical use, but there is a demand for one-point breaking.

By the way, in buffer type gas circuit breakers for lines in large-capacity systems such as 550 KV class, a closing resistance method is adopted in order to suppress closing overvoltage at the time of closing. In this system, a closing resistance contact with a closing resistance is installed in parallel with the main contact of the buffer type gas circuit breaker, and when closing, this closing resistance contact is closed before the main contact, and the closing overvoltage is suppressed by the closing resistance. This is to insert the main contact.

An example of employing the closing resistance method in the buffer type gas circuit breaker as described above will be described below with reference to FIG. 6.

As shown in FIG. 6, the circuit breaker 1 is a horizontal circuit breaker,
The arc extinguishing chamber 2 and the resistance contact section 3 are connected in parallel and arranged in the gas tank 10, and one end of the arc extinguishing chamber 2 and the resistance contact section 3 is connected to the gas tank 10 via a movable support 4 and an insulating tube 5.
is supported by

Further, a mechanism box 7 is attached to the gas tank 10, and a drive section (not shown) is housed inside the mechanism box 7. Also,
The resistance contact portion 3 is a closing resistor 3a.

It is composed of a fixed electrode 3d for the making resistance contact connected in series with the supporting conductor 3c, a movable electrode 3e for the making resistance contact that makes contact with and separates from the fixed electrode 3d, and a supporting conductor 3f supporting it on the movable support 4. .

The fixed electrode 3d for the closing resistance contact is fixed to the support conductor 3c by a known means such as a spring 3g.

Further, the closing resistor 3a is supported by the gas tank 10 by an insulating cylinder 6 and a connecting conductor 9.

On the other hand, the arc extinguishing chamber 2 has a movable part consisting of a main contact movable electrode 2a driven by a drive part (not shown) disposed in a mechanism box 7, a buffer cylinder 2b1 fixed to the movable electrode 2a, and an insulating nozzle 2c. , main contact fixed electrode 2d and insulating tube 2e
It is composed of. The movable side of the arcing chamber and the fixed side of the arcing chamber are connected to other devices via connection conductors 8.

The conventional buffer type gas circuit breaker configured in this way is
It operates as described below.

At the time of closing the circuit breaker, first, the movable electrode 3e for the closing resistance contact and the fixed electrode 3d for the closing resistance contact come into contact, and the closing resistor 3a is closed to the circuit for a certain period of time. Thereafter, the main contact movable electrode 2a and the main contact fixed electrode 2d come into contact, the closing resistor 3a is short-circuited, and the circuit breaker is placed in the closed state. On the other hand, at the time of interruption, first the movable electrode 3e for making resistance contact and the fixed electrode 3d for making resistance contact are opened, and then the movable electrode 2a for main contact and the fixed electrode 2d for main contact are separated, resulting in the interruption state.

(Problems to be Solved by the Invention) However, the conventional closing resistance buffer type gas circuit breaker as described above has the following problems to be solved.

That is, since the closing resistor 3a is configured in a parallel positional relationship with the arc extinguishing chamber 2, there is a drawback that the inner diameter of the gas tank 10 becomes large and a large installation space is required. In addition, when interrupting the current, the movable electrode 2 for the main contact of the circuit breaker 1
An arc occurs between a and the main contact fixed electrode 2d, but
This arc is extinguished by spraying gas compressed by the buffer cylinder 2b along the insulating nozzle 2C. However, at this time, a large amount of hot gas heated by the arc is generated. Since this hot gas flows in the direction of the arrow in Fig. 6, the insulation performance near the insulating tube 6 disposed downstream of the hot gas decreases significantly, and the insulating tube 6 has weaker insulation performance than the gas cap. 6, the insulation performance in the creeping direction may deteriorate, and there is a drawback that the insulation performance to ground decreases immediately after the cut-off.

The present invention was proposed in order to eliminate the above-mentioned drawbacks, and an object of the present invention is to provide a puffer type gas circuit breaker with closing resistance that requires less installation space.

[Structure of the Invention (Means for Solving the Problems)] In order to achieve the above object, the present invention provides a closing resistor that is housed in a tank filled with an insulating gas and that suppresses overvoltage that occurs when closing. In a closing resistive buffer type gas circuit breaker in which a resistive contact part in which a contact and a closing resistor are connected in series and a main contact of the circuit breaker are electrically connected in parallel, the back side of the fixed electrode support structure of the main contact. A plurality of closing resistors are distributed parallel to the axis of the main contact on substantially the same circumference centered on the axis of the main contact, and both ends of the closing resistors are connected to the fixed electrode support structure. It is characterized by being configured to be insulated and supported.

(Function) In the closing resistance buffer type gas circuit breaker of the present invention, the closing resistor is divided and arranged on the back side of the fixed electrode support structure of the main contact, so the entire device can be downsized, and the closing resistance can be made from the gas tank side. Since the structure does not insulate and support the resistor, the ground insulation performance does not deteriorate immediately after the current is cut off.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of one embodiment of the present invention, FIG. 2 is a detailed view of the resistor insulation support structure of FIG. 1, FIGS. 3, 4,
Figure 5 shows the arrows A-A and B-B in Figure 2, respectively.
FIG. 3 is a cross-sectional view taken along line CC. Note that the same parts as those of the conventional circuit breaker described above will be described with the same reference numerals.

As shown in FIG. 1, the circuit breaker 1 is a horizontal circuit breaker,
The arc extinguishing chamber 2 and the resistance contact section 3 are connected in parallel and arranged in the gas tank 10, and one end of the arc extinguishing chamber 2 and the resistance contact section 3 is connected to the gas tank 10 via a movable support 4 and an insulating tube 5.
is supported by

Further, a mechanism box 7 is attached to the gas tank 10, and a drive section (not shown) is housed inside the mechanism box 7. Also,
The resistance contact portion 3 is a closing resistor 3a.

A connecting conductor 3b, a fixed electrode 3d for a making resistance contact connected in series with these via a supporting conductor 3C, a movable electrode 3e for a making resistance contact that comes into contact with and separates from the connecting conductor 3b, and a supporting conductor 3f that supports it on a movable support 4. It is configured. The fixed electrode 3d for the closing resistance contact is fixed to the support conductor 3C by known means such as a spring 3g. Further, the closing resistor 3a is insulated and supported by the fixed electrode support structure 21 on the back surface of the fixed electrode support structure 21 via insulating rods 31 and 32. As shown in FIGS. 3 and 4, the closing resistor 3a is
The fixed electrode support structure 21 is divided into four parts on the same circumference on the same circumference centered on the axis of the arc extinguishing chamber 2 on the back side thereof, parallel to the axis of the main contact part. The individual closing resistors 3a are connected to holding fittings 33, 34 which also serve as electric field mitigation shields, as shown in FIG. In addition, the fixed electrode support structure 2 of the closing resistor 3a
One side is connected to an insulating support rod 31, and the other end of the insulating support rod 31 is connected to a fitting part 35 provided on the fixed electrode support structure 21.
is inserted and supported. The other end of the closing resistor 3a is
It is fastened to the fixed electrode support structure 21 with a fixing bolt 37, and is fastened to an insulating support rod 32 protruding from the back side of the fixed electrode support structure 21 with a fixing bolt 36. Also,
As shown in FIG. 3, one insulating support rod 32 insulates and supports two closing resistors 3a. The individual closing resistors 3a are electrically connected in series by the connection conductor 38 shown in FIG.
to the supporting conductor 3C arranged between a and the connecting conductor 39
It is electrically connected to the fixed electrode support structure 21 via. Furthermore, as shown in FIGS. 4 and 5, the insulating support rods 31 and 32 and the closing resistor 3a are prevented from blocking the hot gas exhaust space of the hot gas exhaust port 22 provided in the fixed electrode support structure 21. It is located in

As described above, according to this embodiment, the closing resistor 3a is divided and arranged on the back side of the fixed electrode support structure 21 on substantially the same circumference centered on the axis of the main contact, parallel to the axis of the main contact. As a result, the length of each closing resistor 3a can be reduced, and the closing resistors can be arranged without increasing the inner diameter of the tank, resulting in an extremely compact configuration. Further, since the hot gas exhaust port 22 provided in the fixed electrode support structure 21 is not blocked, the blocking performance and insulation performance are excellent. Furthermore, since the insulating support structure of the closing resistor 3a is made by a combination of fitting structure and bolt fastening, the closing resistor can be easily removed from the opening on the opposite side of the mechanism box 7 of the gas tank 10. When inspecting the arc extinguishing chamber 2, it is possible to have a configuration with extremely good workability.

[Effects of the Invention] As explained above, according to the present invention, a plurality of closing resistors are arranged on the fixed electrode support structure 21 side on substantially the same circumference around the axis of the main contact. The internal diameter of the gas tank and The overall length is reduced, and the discharge space can be secured without the closing resistor interfering with the discharge of hot gas heated by the arc generated at the time of disconnection to the fixed electrode side, resulting in improved interrupting performance and insulation performance. A puffer-type gas circuit breaker with a closing resistor that does not cause a drop in performance, and the closing resistor can be easily removed from the opening on the opposite side of the gas tank's mechanism box, making inspection work easier and requiring less installation space. can be provided.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, FIG. 2 is a detailed view of the resistor insulation support structure of FIG. 1, and FIG. 3 is a detailed view of the resistor insulation support structure of FIG. Figures 4 and 5 are arrows A-A in Figure 2, respectively;
A cross-sectional view taken along lines B-B and C-C, and FIG. 6 is a cross-sectional view of a conventional puffer type gas circuit breaker with closing resistance. 1... Circuit breaker 2... Arc extinguishing chamber 2a...
- Movable electrode for main contact 2b... Buffer cylinder 2d... Fixed electrode for main contact 2c... Insulating nozzle 2e... Insulating tube 3... Resistance contact part 3a... Closing resistor 3
b... Connection conductor 3c... Support conductor 3d.
...Fixed electrode for making resistance contact 3e...Movable electrode for making resistance contact 3f...Support conductor 3g...Spring 4...
Movable support 5.6... Insulating tube 7... Mechanism box 8, 9... Connection conductor 10... Gas tank 21... Fixed electrode support structure 22... Hot gas exhaust port 31.32. ...Insulating rod 33.34...Press fitting 35...Fitting part 36.
37...Fixing bolt 38.39...Connecting conductor (8733) Agent: Patent attorney Yoshiaki Inomata (and others)
1 person) Diagram potato

Claims (1)

[Claims] The resistor contact section, which is housed in a tank filled with insulating gas and has a closing resistor and a closing resistor connected in series to suppress overvoltage that occurs when closing, is electrically paralleled to the main contact of the circuit breaker. In a puffer type gas circuit breaker with a closing resistor connected to the main contact, a plurality of closing resistors are connected to the back side of the fixed electrode support structure of the main contact on substantially the same circumference centered on the axis of the main contact. 1. A puffer type gas circuit breaker with a closing resistor, characterized in that the closing resistor is arranged in a distributed manner parallel to the axis of the closing resistor, and both ends of the closing resistor are insulated and supported from the fixed electrode support structure.