JPH0244620A - Gas insulation opening/closing device - Google Patents

Abstract

PURPOSE:To reduce the opening/closing surge voltage by allowing a pushing member, which moves with opening/closing motion of a main movable contacting piece, to contact a pushed member furnished at a driven member to drive an aux. movable contacting piece so as to press the driving member, and thereby preventing generation of re-arcing phenomenon at the time charging current is shut. CONSTITUTION:When a circuit opening command is given, a main movable contacting piece 16 makes opening action at the same speed as a conventional breaker. At this time, an aux. movable contacting piece 17 remains at a standstill. When the contacting piece 16 moves for a distance corresponding to the dimension L, a boss 25 contacts a pin 24. When the main movable contacting piece 16 further moves, the boss 25 presses the p in 24 upward to allow a lever 21 to be pressed upward, and the aux. movable contacting piece 17 is driven to the open circuit side. In the condition opening the circuit is completed, the contacting piece 17 is so set as to intrude into the contacting piece 16. Thus the aux. movable contacting piece 17 is left even when the main movable contacting piece 16 is opened at the conventional speed, so that the actual interpolar gas is short, and the generated surge voltage is sufficiently small even though electric discharge is generated in this gap.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a gas insulated switch which has been improved so that a restriking phenomenon does not occur when charging current is cut off.

(Prior Art) In recent years, gas-insulated switchgears have been widely used as switchgears in substations. In particular, in disconnectors used in gas-insulated switchgear of 300KV class or higher, it is known that when cutting off the charging current, the re-ignition phenomenon is repeated and excessive switching nerge is generated, causing the entire gas-insulated switchgear to This has become a problem in terms of insulation performance.

The mechanism of such switching surge generation will be explained below using a disconnector as an example. The opening/closing speed of a circuit breaker is slow, unlike a normal circuit breaker, and even for high-speed circuit breakers, the opening/closing speed is approximately 2 m/s.
It is about ~3m/S. Therefore, when the circuit is opened, the charging current is interrupted midway, but a voltage equal to the difference between the residual voltage on the load side and the operating voltage on the power supply side is generated between the poles, and increases from zero immediately after the interruption.

However, at this time, since the opening speed of the movable contact of the disconnector is slow, the recovery voltage between the poles exceeds the withstand voltage value between the poles, leading to restriking, and an excessive switching surge occurs. This switching surge propagates inside the gas-insulated switchgear, and is repeatedly reflected and transmitted at the branch and end sections, and a maximum surge of 3p, u (approximately three times the peak value of the power supply voltage) may occur. The insulation performance of gas-insulated switchgear was threatened.

In addition, in the insulation design of gas-insulated switchgear, the dimensions of each part are determined based on the lightning impulse withstand voltage value, since the lightning impulse withstand voltage value is usually the most severe.
If we try to achieve economic efficiency in switchgear equipment by using reduced insulation for insulation coordination as in KV or UHV, the opening and closing cage becomes difficult for the equipment, and the effect of reduced insulation will be significantly reduced.

The structure of a conventional disconnector as described above is shown in FIG. That is, the inside of the metal container 1 is filled with an insulating gas 2 such as SF6 gas, and the current-carrying conductors 3 and 4 are supported and fixed by an insulating spacer 5. A fixed side contact part 6 and a movable side contact part 7 of the disconnector are disposed facing each other, and a movable contact 8 for opening and closing the movable side contact part 7 is connected to an insulating rod 9.
, crosshead 10. It is configured to be driven by a main shaft 13 via a link 11 and a lever 12.

Further, this main shaft 13 is rotationally driven by an operating device 14 installed outside the disconnector main body, and the rotational driving force is converted into a linear reciprocating motion by a guide rod 15 that slides on the crosshead 10. The movable contact 8 is configured to be driven to open and close in the vertical direction.

(Problem to be Solved by the Invention) However, in the disconnector having the above configuration, the movable contact 8 has a capacity to conduct the required rated current and short-time withstand current in an open state, and Since the temperature rise must be kept below the value specified by the standard, a conductive material such as copper or aluminum must be used and a sufficient current-carrying cross-sectional area must be ensured.

In addition, in the complete open circuit state, in order to ensure the inter-electrode insulation performance specified in the standard, the distance between the electrodes must be set to a certain extent.

Although the shape and weight of the entire movable contact are determined to satisfy these conditions, it is quite heavy. Furthermore, in order to drive the movable contactor 8, members such as the insulating rod 9 and the crosshead 10 are required, which further increases the weight of the entire movable system.

Therefore, in order to suppress the opening/closing surge, the movable contact 8
It is nearly impossible to operate at super high speed.

If this were to be possible, an operating device with enormous operating force would be required, which would not only be an impediment to the layout of gas-insulated switchgear, but also make it difficult to ensure equipment reliability. There was a drawback.

The present invention was proposed in order to eliminate the above-mentioned drawbacks, and its purpose is to provide a gas-insulated switch that prevents the occurrence of the restriking phenomenon when charging current is cut off and reduces switching surge voltage. It is in.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a gas-insulated switch whose main movable contact is driven by a switching mechanism and performs opening and closing operations by performing linear reciprocating motion via an insulating rod. An auxiliary movable contact is provided inside the main movable contact, and when the main movable contact reaches a predetermined stroke, a pressing member that moves with the opening/closing operation of the main movable contact moves the auxiliary movable contact into the auxiliary movable contact. The device is configured to come into contact with a pressed member disposed on a drive member that drives the child, and press the drive member.

(Function) According to the gas insulated switch of the present invention, even if the main movable contact opens at the conventional speed, the auxiliary movable contact remains, so the gap between the poles can be kept short, and the gap between the poles can be kept short. Since the surge voltage generated in the engine can be suppressed to a low level, the occurrence of the restriking phenomenon can be prevented.

(Example) Hereinafter, an example of the present invention will be specifically described based on FIGS. 1 to 4. Note that the same members as those of the conventional type shown in FIG. 9 are given the same reference numerals, and explanations thereof will be omitted.

In this embodiment, as shown in FIG. 1, an auxiliary movable contact 17 is provided inside the main movable contact 16, and this auxiliary movable contact 17 has a drive member for driving it. , an insulating rod 18, a metal fitting 19, a link 20, a lever 21, and a shaft 22 are provided. In addition, the lever 21
is rotatably arranged around a shaft 22, and a pin 24, which is a pressed member, is provided at the center thereof.

On the other hand, the main movable contact 16 has an insulating rod 9 as in the conventional case.
, crosshead 10. It is connected to an externally provided operating device by a main shaft 13 via a link 11 and a lever 12.

Further, the crosshead 10 is provided with a boss 25 which is a suppressing member that comes into contact with a pin 24 provided on the lever 21, and is configured to come into contact with the pin 24 when the crosshead 10 moves by a certain amount in the opening direction. has been done.

This dimension is determined by the main movable contact 16 as shown in FIG.
The distance G between the contact portion 6 and the fixed contact portion 6 is set to be a distance that can generally withstand the inter-electrode recovery voltage.

The pin 24 is provided at a position 1 from the shaft 22 and at a position 2 from the connecting portion 23 of the link 20 and the lever 21. Further, the auxiliary movable contact 17 does not need to have current-carrying performance, but it needs to be conductive, and in order to enable ultra-high-speed driving, it must be made of as light a member as possible, for example,
A wire-like rod made of aluminum or a conductive resin is preferable.

Furthermore, the operating device is configured to have a driving force comparable to that of a conventional disconnector, and thereby the main movable contact 16 is driven at a speed of approximately 3 m/SeC. .

In the disconnector of this embodiment having such a configuration, opening/closing operations are performed as described below.

That is, when an opening command is issued in the closed circuit state shown in FIG. 1, the main movable contact 16 opens at the same speed as a conventional disconnector. However, at this time, the boss 25 provided on the crosshead 10 is not in contact with the pin 24 provided on the lever 21, so the auxiliary movable contact 17 does not move.

Next, as shown in FIG. 2, when the main movable contact 16 moves by a certain amount, the boss 25 comes into contact with the pin 24. In this state, a recovery voltage is generated between the electrodes, but a spark is generated at the portion q where the distance between the electrodes is the smallest. However, since the gap dimension q is very small, the generated surge is also very small.

Roughly speaking, when the main movable contact 16 moves, the boss 25 presses the pin 24 upward as shown in FIG. Drive to the side. At this time, the opening speed of the auxiliary movable contact 17 is determined by the position of the pin 24 by 1. Determined by Lz.

That is, when the opening speed of the main movable contact 16 is v□, the speed V of the auxiliary movable contact 17 is v=vo x (it-HL2)/L+, and Vo
=3m/s, it=Lz, then it becomes V-6m/S.

As shown in FIG. 4, the auxiliary movable contact 17 is set to enter inside the main movable contact 16 when the circuit opening operation is completed. Therefore, the auxiliary movable contact 17 has no influence on the interpole insulation performance of the disconnector in the completed state of opening, and the required performance can be ensured.

Note that during the circuit-closing operation, the auxiliary movable contact 17 falls due to its own weight, so the main movable contact 16 has a faster circuit-closing speed and is thrown in ahead of the auxiliary movable contact 17.

In this way, according to this embodiment, the auxiliary movable contact 17 can be made very light, so the driving force required to drive it at ultra-high speed is extremely small, so the conventional operating device can be used as is. can do.

Furthermore, the opening speed of the auxiliary movable contactor 17 is 1/9.2.
By changing the ratio, it is possible to obtain the required opening speed according to the applied rated voltage, etc. For example, Vo
= am/s, IJ, t: 12=1:2, the opening speed of the auxiliary movable contact 17 is 9 m/s.
It can be S.

In this way, in the disconnector of this embodiment, even if the main movable contact 16 opens at the conventional speed, the auxiliary movable contact 17 remains, so the actual gap between poles is q. Even if a discharge occurs between this short gap, the generated surge voltage is sufficiently small.

In addition, in a state where the main movable contact 16 has moved to a position where it can sufficiently withstand the recovery voltage, the auxiliary movable contact 17
opens at an ultra-high speed, so against the increase in recovery voltage between poles,
The recovery speed of interelectrode insulation performance is faster, and it becomes possible to shut off without causing restriking.

*Other embodiments* Note that the present invention is not limited to the embodiments described above, and a return spring 31 may be provided on the auxiliary movable contact 30 as shown in FIG. . This is because if the return operation of the auxiliary movable contactor 30 is performed by its own weight, there is a drawback that a sufficient return operation cannot be performed depending on the arrangement orientation of the disconnector. Note that a weak spring that can overcome the weight of the auxiliary movable contact 30 is sufficient as the return spring 31.

Further, as shown in FIG. 6, a boss 40 provided on the crosshead is provided with an abutting portion 41 that abuts the pin 24 when the circuit is opened.
Furthermore, a contact portion 42 is provided which contacts the pin 24 during circuit closing and returns the auxiliary movable contact 17 to its original position.
may be provided. In this case, upon completion of the circuit closing operation,
The auxiliary movable contact 17 can be completely returned to its original position.

Further, as shown in FIG. 7, an auxiliary contact 50 is provided within the fixed side contact portion 6. In the closed circuit state, the auxiliary movable contact 17 comes into contact with the auxiliary contact 50, and the structure is such that no discharge occurs before the auxiliary movable contact 17 is operated. In this case, the boss is set at the sixth position so that the auxiliary movable contact 17 completely enters the inside of the auxiliary contact 50 when the circuit is closed.
As shown in the figure, it is configured to have two abutting portions 41 and 42.

Further, as shown in FIG. 8, the tip of the auxiliary movable contact 60 is made spherical in order to increase the curvature.

In this case, the insulation performance between electrodes when the auxiliary movable contact 60 is opened is further improved.

[Effects of the Invention] As described above, according to the present invention, an auxiliary movable contact is provided inside the main movable contact, and when the main movable contact reaches a predetermined stroke, the main movable contact opens and closes. When the charging current is cut off, the suppression member that moves with the operation comes into contact with the pressed member provided on the drive member that drives the auxiliary movable contact and presses the drive member. It is possible to provide a gas insulated switch that prevents the occurrence of restriking phenomenon and reduces switching surge voltage.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the present invention using a disconnector as an example, FIGS. 2 to 4 are sectional views showing its operating state, and FIGS. Cross-sectional view showing an embodiment of
The figure is a sectional view showing a conventional disconnector. DESCRIPTION OF SYMBOLS 1... Metal container, 2... Insulating gas, 3, 4... Current-carrying conductor, 5... Insulating spacer, 6... Fixed side contact part, 7゛... Movable side contact part, 8 ...Movable contact, 9.
...Insulating rod, 10...Crosshead, 11...
Link, 12...Lever, 13...Main shaft, 14...
- Operating device, 15... Guide rod, 16... Main movable contact, 17... Auxiliary movable contact, 18... Insulating rod, 19... Metal fitting, 20... Link, 21...・
・Lever, 22...Shaft, 23...Connection part, 24...
・Pin, 25...Boss, 26...Stopper, 30・
...Auxiliary movable contact, 31...Returning spring, 40...
・Boss, 41.42... Contact portion, 50... Auxiliary contact, 60... Auxiliary movable contact. 3 2nd diagram 2nd leap diagram

Claims (1)

[Claims] In a gas-insulated switch in which a main movable contact is driven by an opening/closing mechanism and performs opening/closing operations by performing linear reciprocating motion via an insulating rod, an auxiliary movable contact is provided inside the main movable contact. , when the main movable contact reaches a predetermined stroke, a pressing member that moves with the opening/closing operation of the main movable contact comes into contact with a pressed member provided on a drive member that drives the auxiliary movable contact. , A gas insulated switch characterized in that it is configured to press the driving member.