US3256415A

US3256415A - Compressed gas electrical switch of tank type construction with multiple interruption and closed gas circulation system

Info

Publication number: US3256415A
Application number: US316569A
Authority: US
Inventors: Ruffieux Stanislas
Original assignee: BBC Brown Boveri France SA
Current assignee: BBC Brown Boveri AG Germany; BBC Brown Boveri France SA
Priority date: 1962-11-08
Filing date: 1963-10-16
Publication date: 1966-06-14
Anticipated expiration: 1983-06-14
Also published as: AT242779B; CH397819A; GB1004378A

Description

June 14, 1966 S. RUFFIEUX COMPRESSED GAS ELECTRICAL SWITCH OF TANK TYPE CONSTRUCTION WITH MULTIP'IJE INTERRUPTION AND CLOSED GAS CIRCULATION SYSTEM Filed Oct. 16, 1963 INVENTOR SfanksLas Ruffieux W W4; A)! I ATTORNEYS United States Patent COMPRESSED GAS ELECTRICAL SWITCH OF TANK TYPE CONSTRUCTION WITH MULTIPLE INTERRUPTION AND CLOSED GAS CIRCULA- TION SYSTEM Stanislas Rufiieux, Baden, Switzerland, assignor to Aktiengesellschaft Brown, Boveri & Cie, Baden, Switzerland, a joint-stock company Filed Oct. 16, 1963, Ser. No. 316,569 Claims priority, application Switzerland, Nov. 8, 1962,

1 Claim. (Cl. 200-148) The present invention relates to a gas blast circuit breaker of the enclosed vessel type with a closed gas circuit and several power interrupter points connected in series, the arcs formed at these points during circuit interruption being extinguished by means of a gas blast, in particular SP which is supplied from a high pressure chamber within the vessel and is trapped in a low pressure chamber in the vessel after flowing through the interrupting zone. In one known type of gas circuit breaker of this type, SP gas is used as the extinguishing medium, which during the interrupting process is supplied at high pressure along the axis of the vessel along which the interrupters are arranged. The gas at high pressure is thereby contained in a divided receiver which is situated partly at the head of the circuit breaker and partly inside the vessel itself. The circuit breaker vessel remains at low pressure and acts as a receiver for the exhaust gases from the inter-raptors. The supply of the extinguishing gas to the interrupting chambers takes place through relatively long and thin pipes thus causing a comparatively large pressure drop in the pipes on the one hand and resulting in a moderate delay on the other hand as a result of the poor flow characteristics, especially with SF until the gas pressure wave reaches the interrupters. Due to this, the rupturing capacity as well as the operating time of the circuit breaker will be disadvanta-geously influenced. The purpose of the present invention is to provide [a novel construction of a pressure gas circuit breaker of the enclosed vessel type with which the pressure loss in the extinguishing .gas supply system as well as the operating time will be reduced to a minimum, whilst at the same time the best possible utilization of the interrupters will be obtained with respect to their rupturing capacity. According to the invention the circuit breaker vessel is subdivided into several high and low pressure chambers along its length by transverse insulating partitions, by which means the individual interrupters are arranged essentially along the axis of the vessel so that each partition contains at least one point of power interruption constituted by a pair of separable contacts which are blasted with the pressurized gas.

In the accompanying drawing, an example of the form of the gas circuit breaker is represented, partly in central vertical section, 'with reference to which the principle of the invention can be more closely explained. An

elongated metal cylindrical vessel at earth potential comprising several sections is denoted by 1. The vessel is subdivided by three axially spaced, transverse insulating partitions 2a, 2b, 2c, into four-chambers, there being two high pressure chambers 3a, 3b and two low pressure chambers 4a, 4b in alternation. The partitions 2b and 2c are moreover those which serve to assist in interruption of the power, being those appertaining to the interrupter points, 5b, 5c arranged along the axis or the vessel whilst the partition 2a is associated with the third power interruption point 5a and a disconnecting switch 6a. The movable pin contact 5d of each power interrupter point is located inside the tubular part of a blast valve 5 which operates with the contact piece 5d, whilst the stationary nozzle type contact 5e of each power inter- 3,256,415 Patented June 14, 1966 r-upter point is fixed to the appertaining one of the partitions 2a to 2c. The voltage disconnecting switch 6a has a movable pin contact 6b placed opposite the fixed tulip contact 6d. This tulip contact is arranged in the conductive supporting piece 6c which is itself supported and insulated from the breaker vessel 1 by the upper insulator 10a. The perforated tube 7a is provided to conduct the current between the power interrupter points 5a and 5b, whilst a further perforated tube 7b acts as the connection between the current conductor 8b and the lower breaker terminal 9b. In the same way, the fixed contact 6d is electrically connected with the upper breaker terminal 9a across the conductive supporting piece 6c and the conductor 8a. The lower insulator 10b serves as the mechanical support for the tube 7b in the tank 1. In order to operate the power interrupters, operating mechanisms 12a, 12b are provided, whilst the operating commands are transmitted by known technical means through the hollow insulators 11a, 11b. With the construction of the illustrated embodiment, the operating mechanism 12a controls both the power interrupter point 5a and the voltage disconnecting switch 6a whilst the operating mechanism 12b controls both of the power interrupter points 5b and 5c. A coupling rod 14 connecting the two operating mechanisms is located inside the pipe 13, so that, for example, if the operating mechanism 12a operates, then the operating mechanism 12b will be pneumatically operated as well. The pipe 13 is equipped with a lead in pipe 15 through which it is connected to a closed gas system, not illustrated. The high pressure gas lead in through the pipe 13 then enters the high pressure chambers 3a, 3b. The return path of the low pressure gas from the low pressure chambers 4a, 4b is through the pipe 16 whose exit or lead-01f pipe 17 is connected to the entrance side of the closed gas system.

The operation of the improved circuit breaker is as follows:

As depicted in the drawing, the overall switch mechanism is in the switched-out position. The disconnecting switch 6a is thereby open, which means that the space between the contacts 6b, 6d is filled with high pressure gas acting as insulation. The power internupters 5a to 50 which are of the impulse type, constructed according to well known principles, are shown in the closed position. In this position, each of the three movable pin contacts 5d is held fast against the companion fixed nozzle contact 5e and the movable blast valve sleeve part 5 closes the connection between the high pressure the electrical circuit through the switch mechanism since the contact sets 5d, 5c of the three power interrupter points 5a to Sc were already closed. When the overall switch mechanism is in the closed position, the current path follows the

parts

9a, 8a, 60, 6d, 6b, 5d, 52, 7a, the corresponding parts of the interrupters 5b, 50 as well as through 7b, 8b and 9b.- The operating mechanism.|for the interrupters 5a, 5b, 50, not shown, is so constructed according to known principles, that each contact 5a as well as the blast valve part 5 the blast valve and the interrupter being combined, remain stationary during the closing operation. For the opening operation, the operating mechanism 12a will receive an opening command, for example, causing it to trip, whereby the transmitting system which is located inside the insulator 11a, the transmitting system not being shown in detail, the operating mechanism for the power internuptors 5a, as well as the disconnecting switch 6a will be set in motion, so that the blast valve part 5 and the contacts 5d, 5e open at the same time. The arcs between the contacts at the time being considered will be acted upon and extinguished by the gas flowing between the high pressure chambers 3a, 3b and the low pressure chambers 4a, 4b. Therewith, the extinguishing gas flows around the nozzle shaped contact 5e flowing next through the inside of the pipe 7a or 7b and then finally through the perforations of the pipe into the chamber 4a or 4b. The beginning of the contact separation between the contacts 6b, 6d of the disconnecting switch results thereby with a certain delay according to known principles as soon as the arcs are extinguished at the power interruption points. Both the remaining power interrupters 5b, 5c act in the same way as the interrupter 5a. The simultaneous operation follows as a result of the coupling rod 14 by means of which the operating mechanism 12b is made to follow a similar operation. After reaching a suflicient contact separation at the disconnecting switch 6a, the impulse type power interrupter points 5a to Sc reelose, and thereby the blast valve part 5 as well, according to known principles, so that the insulation of the breaker in the open position will now be determined by the disconnecting switch alone.

The invention is not limited to the form of the example in the enclosed drawing. It could happen in certain cases that the power interrupters could be so suitably constructed that the power interrupter contacts remain separated in the open posit-ion thereby undertaking the insulation of the switched-out breaker, so that the separate disconnecting switch could be removed. In this case the interrupter contacts would also then have to perform the closing operation of the breaker.

I claim:

In a circuit breaker of the gas blast type wherein the gasflows ina closed circuit, the combination comprising an elongated vessel, said vessel including a plurality of transverse partitions dividing the interior of said vessel into a plurality of high pressure and low pressure gas chambers, each said partition separating a high pressure chamber from a low pressure chamber, a power interrupter point mounted upon each said partition, each said power interrupter point being constituted by a pair of contact members which when separated are blasted with a pressurized gas flowing from a high pressure chamber to an adjacent low pressure chamber, each said pair of contact members being constituted by a stationary nozzle member mounted in the partition member correlated thereto and a movable pin member, a blast valve for each power interrupter point, each said blast valve including a valve sleeve surrounding the pin contact member and being movable from its seat on the nozzle contact member to permit flow of pressurized gas through said nozzle contact member into the adjacent low pressure chamber when separated from its pin contact member, means connecting the contact members of all of said power interrupting points in series between inlet and outlet terminals provided respectively at the opposite ends of said vessel, said connecting means including perforated sleeves extending axially within said low pres-- FOREIGN PATENTS 670,347 3/1962 Canada. 1,287,957 2/1962 France.

592,965 10/1947 Great Britain.

KATHLEEN H. C-LAFFY, Primary Examiner.

P. E. CRAWFORD, Assistant Examiner.