US3489873A - Triggered vacuum type circuit interrupter - Google Patents

Triggered vacuum type circuit interrupter Download PDF

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Publication number
US3489873A
US3489873A US680809A US3489873DA US3489873A US 3489873 A US3489873 A US 3489873A US 680809 A US680809 A US 680809A US 3489873D A US3489873D A US 3489873DA US 3489873 A US3489873 A US 3489873A
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United States
Prior art keywords
arc
trigger
gap
contacts
contact
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Expired - Lifetime
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US680809A
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English (en)
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Donald R Kurtz
Joseph C Sofianek
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General Electric Co
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General Electric Co
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
    • H01H33/66—Vacuum switches
    • H01H33/664—Contacts; Arc-extinguishing means, e.g. arcing rings
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
    • H02H7/16—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for capacitors

Definitions

  • a triggered vacuum interrupter comprising relatively movable contacts and spaced-apart, stationary annular arc-runners respectively surrounding the contacts with clearance.
  • Triggering means is provided in one of the arcr-unners in a position spaced radially outward from its associated contact for initiating an arc between the arc runners in a position spaced from the contacts, after which the contacts are driven into engagement.
  • This invention relates to a vacuum type circuit controller and, more particularly, a vacuum type circuit interrupter which includes triggering means for initiating an arc when the interrupter is in fully-open position.
  • U.S. Patent 3,319,121-Lee assigned to the assignee of the present invention, there is disclosed a vacuum type circuit interrupter that comprises relatively movable contacts and triggering means for initiating an arc between the contacts when they are in a spaced-apart fully open position. After the arc is initiated, the contacts are driven together to extinguish the arc and provide a solid metallic path through the interrupter for carrying the current previously carried by the arc. This is the type of closing duty that our triggered vacuum interrupter must be capable of handling.
  • This type of closing duty differs significantly from that imposed on the conventional vacuum type interrupter.
  • closing is initiated prior to any arcing between the contacts; and any arcing that does occur during closing is initiated only when the gap is very short, for example, just prior to the contacts engaging or during any contact-bouncing that occurs immediately following initial engagement.
  • the arcing duration is very short, and there is little chance that the contacts of a well-designed interrupter will be damaged by the closing.
  • arcing persists over a much longer period, occurring during the entire closing operation, and this increases the chance for impairment of the contacts.
  • An object of our invention is to reduce the chance for impairment of the contacts of such a triggered vacuum interrupter during a closing operation.
  • first contact and a second contact movable into and out of engagement therewith.
  • a first annular arc runner surrounds the first contact and is electrically connected thereto.
  • a second annular arc runner surrounds the second contact and is electrically connected thereto but is physically spaced therefrom by a clearance space surrounding the second contact.
  • the annular arc runners are mounted in generally-aligned, spaced-apart relationship with a primary arcing gap therebetween.
  • means including a trigger gap for injecting a concentration of charged conduction carriers into the primary gap in response to a predetermined signal being applied across the trigger gap, thereby causing an are to be established between the arc runners across the primary gap.
  • the second contact is driven intoV engagement with the rst contact.
  • FIG. l is a sectional view through a triggered vacuum interrupter embodying one form of our invention.
  • FIG. 2 is a schematic diagram showing an application of our triggered vacuum interrupter.
  • FIG. 3 illustrates a modified form of the invention.
  • a vacuum-type circuit controller or interrupter comprising a highly evacuated sealed envelope 10.
  • This envelope 10 comprises a cylindrical casing 11 of insulating material and a pair of metallic end caps 12 and 13 at opposite ends of the casing 11. Suitable seals 14 are provided between the end caps and the casing 11 to provide a vacuum-tight joint between these parts.
  • the normal pressure within the envelope is lower than 10-4 mm. of mercury, so that a reasonable assurance is had that the mean free path for all electrons will be longer than the potential breakdown paths in the mterrupter.
  • the internal insulating surfaces of the casing 11 are protected from the condensation of arc-generated metallic vapors thereon by means of a tubular metallic shield 15 suitably supported on the casing 11 and preferably isolated from both end caps 12 and 13.
  • This shield acts in a known manner to intercept arc-generated metallic vapors before they can reach the casing 11.
  • the upper electrode 17 is a stationary electrode suitably attached to a conductive rod 17a, which at its upper end is united to the upper end cap 12.
  • the lower electrode 18 is referred to hereinafter as the movable electrode although only a portion of this lower electrode is movable.
  • the movable portion of the lower electrode is a centrally-disposed part 20 referred to herematter as a movable contact.
  • This contact 20 is suitably attached to a conductive operating rod 21, which is suitably mounted for vertical movement along the axis of the rod 21.
  • a conductive operating rod 21 which is suitably mounted for vertical movement along the axis of the rod 21.
  • the movable contact 20 is shown in its uppermost position engaging a stationary contact 24 constituting a part of the stationnary electrode 17.
  • the interrupter is closed and current can flow therethrough via the conductive rod 17a, stationary Contact 24, movable contact 20, and conductive rod 21.
  • Downward movement of the rod 21 separates the movable contact 20 from the stationary contact 24 and thereby opens the interrupter.
  • the position of the parts when the interrupter is fully open is depicted with solid lines in FIG. l, where the movable contact 24 has been withdrawn from the stationary contact through its full downward opening stroke.
  • the movable contact 20 is driven upwardly from its solid line position of FIG.
  • the operating rod 21 projects through an opening in lower end cap 13, and a flexible metallic bellows 29 provides a seal about the rod 21 to allow for vertical motion of the rod without impairing the vacuum inside the envelope 10. As shown in FIG. l, the bellows 29 is secured in sealed relationship at its respective opposite ends to the operating rod 21 and the lower end cap 13.
  • the movable electrode 18 comprises a stationary arc runner 30 in the form of an annular disc surrounding the movable contact 20.
  • This stationary arc runner 30 is mounted on the lower end cap 13 by means of a tubular conductor 32 that is secured at its opposite ends to the end cap 13 and the arc runner 30.
  • the joint between the tubular contact 32 and annular arc runner 30 is located at the inner periphery of the annular arc runner for reasons which will soon be explained in more detail.
  • the movable contact 20 and the annular arc runner 30 are electrically connected together by means of a flexible braid 34 located outside of the evacuated envelope 10.
  • the stationary electrode 17 also includes an annular arc runner surrounding its centrally-disposed contact portion 24.
  • This annular arc runner which is designated 36, is generally aligned with the other arc runner 30 and is spaced therefrom to provide a primary arcing gap 37 of annular configuration between the opposed faces of the arc runners.
  • the annular arc runner 36 is supported on the conductive rod 17a by means of a radially-extending integrally-formed body portion 38 that is suitably brazed at its inner periphery to the rod 17a.
  • This body portion 38 has a tubular portion 38a that is joined to the arc runner 36 at the inner periphery of the arc runner.
  • the movable contact 20 is of the general configuration shown and claimed in U.S. Patents 3,210,505-Porter and 3,185,799-Greenwood et al., assigned to the assignee of the present invention.
  • the Contact 20 is of a cup-shaped configuration and comprises a base and a tubular wall 26 that extends from the base 25 in a direction away from the location of the stationary contact 24.
  • contact 20 is in its dotted-line closed position, engagement is made with the stationary contact 24 along an annular surface near the outer periphery of the contacts.
  • the cup-shaped configuration of the movable contact 20 provides a magnetic force for driving arcs initiated on the contacts radially off the contacts. Even when the intercontact gap is short, the tubular wall 26 provides an immediately-available conductive path along which the lower terminal of the arc can run into proximity with the lower arc runner 30 and transfer thereto.
  • the illustrated vacuum interrupter is a triggered vacuum interrupter and includes trigger means for initiating an arc across the primary gap 37 at a predetermined instant when the interrupter is in its fully-open position of FIG. 1.
  • This trigger means comprises a trigger electrode assembly 40 associated with each arc runner.
  • Each of these trigger electrode assemblies 40 can be of a conventional design, such as is shown and claimed in U.S. Patent 3,087,092-Lafferty, assigned to the assignee of the present invention. These trigger electrode assemblies are identical, and therefore only one will be described.
  • the trigger electrode assembly associated with arc runner 30 comprises a cylindrical ceramic rod 42 extending through the end cap 13 in sealed relationship thereto and fitting into an opening in the arc runner 30.
  • a relatively low voltage pulse applied between trigger electrodes 44 and 46 will initiate a discharge across the trigger gap 47.
  • This discharge will evolve hydrogen from the trigger electrodes.
  • This hydrogen will be immediately ionized 4 by the arc and the ionized hydrogen will be rapidly propagated, or injected, into the primary gap 37.
  • the ionized particles that are injected into the gap are referred to hereinafter as charged conduction carriers.
  • the trigger assembly is located in a recess 39 formed in the active surface of the arc runner. The arc across the primary gap is typically initiated immediately adjacent the periphery of this recess 39.
  • a conductive lead 48 is provided extending through a passageway in the ceramic rod 42. At its inner end, this lead 48 is brazed to a metallic cap 49 which is in electrical contact with trigger electrode 46 and is hermetically sealed to the inner end of the ceramic rod.
  • a suitable pulse forming circuit such as indicated at 50 in FIG. 2, is connected between the lower conductive lead 4S and the conductive rod 21 for applying a voltage pulse between these parts and hence across the trigger gap 47 at a predetermined instant.
  • FIG. 2 is a schematic diagram showing our interrupter applied to protect against overvoltages in the manner disclosed and claimed in the aforesaid Lee patent.
  • the apparatus being protected is a series capacitor 60 connected in a power line 61, and the interrupter is connected thereacross by means of conductors 62 and 64.
  • a voltage sensor 65 turns on the pulseforming circuit 50, which responds by applying a voltage pulse to the trigger gap 47. This immediately sparks over the trigger gap and thus produces an arc across the primary gap 37 of the interrupter.
  • the arc establishes a low resistance path around the protected apparatus 60 through the interrupter and conductors 62 and 64, thus reducing the voltage across 60.
  • the contacts of the interrupter are Adriven into engagement immediately following establishment of the arc. This is done by means of a solenoid 70 connected in the low resistance path. Solenoid 70 drives the operating rod 21 upwardly against a bias-open spring 72, thereby causing the contacts 20 and 24 to engage. This extinguishes the arc and causes the continuing current to flow through the solid metallic path extending through the contacts. When the current through the contacts falls below a predetermined level, the solenoid drops out and the spring 72 reopens the contacts. On opening, the circuit controller can operate in the same manner as a conventional vacuum interrupter, drawing an arc between the contacts 20, 24 and forcing the arc radially outward, where it is extinguished at an early current Zero.
  • the above-described type of closing duty is more likely to impair the contacts of the interrupter than the duty associated with a typical circuit-interrupter closing operation. This is the case because in the present type of closing duty, arcing persists for a much longer period and is thus more likely to erode and overheat the contacts and to produce stronger welds between the contacts when they engage. We are able to overcome this problem by initiating our arc on the arc runners 30, 36 and not on the contacts 20, 24 themselves. In addition, after the arc is initiated, we force it radially outward away from the contacts 20, 24 thus preventing it in most cases from reaching the contacts. Thus, the contacts, when driven into engagement, have not had a long history of arcing just yprior to closing impact and are thus able to withstand closing duty with less chance of impairment.
  • the trigger means 43-47 typically causes the arc across the main gap to be initiated immediately adjacent the mouth of the recess 39, as was pointed out hereinabove.
  • This radially-outward magnetic force results from the fact that current flowing to the arc through each arc runner enters the arc runner at its radially inner periphery and thus forms a loop-shaped path of radially-outwardly bowing configuration, as indicated by the dotted line C in FIG. 1.
  • the magnetic effect of current flowing through a path of this configuration acts, in a known manner, to expand the loop and drive the arc radially outward. Current is forced to enter the arc runner at its radially inner periphery because the tubular conductor 32 or 38a, as the case may be, through which all this current flows is joined to the arc runner at its inner periphery.
  • a factor that further reduces the chance for an arc developing between the contacts 20, 24 after initial establishment of an arc between the arc runners 30, 36 is that the arc voltage of the arc between the arc runners is quite low, and there is thus little voltage available to initiate an arc between the contacts 20, 24 while an arc is burning between the arc runners.
  • This low arc voltage is a characteristic of a vacuum arc, and for currents as high as several thousand amperes, arc voltages of only 30 volts or less will typically be developed between copper electrodes. At much higher currents, the arc voltage typically will still be quite low, eg., under 100 volts.
  • the arc across the primary gap 37 will be extinguished at each current zero; but in the illustrated arrangement the trigger gap will reinitiate it if a pulse is thereafter received from the pulse-forming circuit 50.
  • the pulse-forming circuit 50 will continue to supply pulses to the trigger gap after each current zero if the over-voltage condition persists. Each time the arc across the main gap is reinitiated, it behaves in substantially the same manner as described hereinabove.
  • a trigger gap may be provided for each of the two main electrodes. These two trigger gaps may be sparked over substantially simultaneously each time the primary gap 37 is to be arced over; or the trigger gap associate only with the main electrode that happens to be the cathode at a particular instant can be sparked to arc-over the primary gap 37.
  • the presence of two trigger gaps operated in either of these manners provides greater assurance that operation of the trigger gap will consistently produce arc cover of the primary gap 37.
  • FIG. l shows the two trigger gaps 47 as being disposed in substantially aligned relationship
  • one trigger gap is disposed in a location in its associated arc-runner diametrically-opposed relative to the location of the other trigger gap.
  • This widely offset relationship of the trigger gaps lessens the chance that an arc initiated by one trigger gap will have access to and will damage the trigger gap in the opposite electrode.
  • the arc initiated by one trigger gap is free to move radially outward without passing near the other circumferentially-offset trigger gap.
  • This offset relationship of the trigger gaps is beneficial in protecting the trigger gaps even in a fixed electrode triggered vacuum gap, such as shown, for example, in application S.N. 569,944-Gallagher, filed Aug. 3, 1966, and assigned to the assignee of the present invention.
  • a triggerable vacuum-type circuit controller comprising:
  • circuit controller of claim 1 in combination with means for forcing the net current owing through said arc runners to the location at which substantially all arcs are initiated therebetween by operation of said trigger gap to follow a radially-outwardly bowing path in the region of said arc, whereby a radially-outward magnetic force is developed on said arc to keep it off said contacts during a closing operation.
  • circuit controller of claim 1 in combination with means for carrying current to or from an arc on said annular arc runners compising conducting means located at the inner periphery of each of said annular runners, said conducting means being spaced radiallyinwardly from the location of said trigger gap.
  • circuit controller of claim 1 in combination with a second trigger gap mounted in the other of said arc runners in a position located radially outward from its associated contact.
  • said second contact is of a cup-shaped configuration and comprises a base engageable with said first contact and a tubular wall extending from said base in a direction away from the location of said first contact, said second annular arc runner surrounding said tubular wall and physically separated therefrom by said clearance space.
  • circuit controller of claim 1 in combination with a second trigger gap mounted in the other of said are runners in a position located radially outward from its associated contact, said two trigger gaps being disposed in locations widely offset from each other.
  • circuit controller of claim 7 in combination with means for forcing the net current owing through said are runners to the locations at which substantially all arcs are initiated therebetween by operation of said trigger gaps to follow a radially-outwardly bowing path in the region of said arcs.
  • a triggerable vacuum type circuit controller com prising
  • said trigger gaps being disposed in locations widely oset from each other circumferentially of said electrodes, and

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • High-Tension Arc-Extinguishing Switches Without Spraying Means (AREA)
  • Arc-Extinguishing Devices That Are Switches (AREA)
US680809A 1967-11-06 1967-11-06 Triggered vacuum type circuit interrupter Expired - Lifetime US3489873A (en)

Applications Claiming Priority (1)

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US68080967A 1967-11-06 1967-11-06

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US (1) US3489873A (de)
JP (1) JPS4712982B1 (de)
CH (1) CH476387A (de)
DE (1) DE1806880A1 (de)
FR (1) FR1601758A (de)
GB (1) GB1237466A (de)
SE (1) SE347386B (de)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3614532A (en) * 1970-06-01 1971-10-19 Gen Electric Triggered vacuum gap keep-alive circuit
US4041261A (en) * 1975-06-24 1977-08-09 General Electric Company High current capacity rod array vacuum arc discharge device
CN101086662B (zh) * 2006-06-09 2010-04-07 李玉敏 磁感应真空复式智能控制器
EP3561846A1 (de) * 2018-04-27 2019-10-30 Siemens Aktiengesellschaft Vakuum-leistungsschalter
EP3561845A1 (de) * 2018-04-27 2019-10-30 Siemens Aktiengesellschaft Vakuum-leistungsschalterröhre
EP3561972A1 (de) * 2018-04-27 2019-10-30 Siemens Aktiengesellschaft Netzbeeinflussungsanlage
US10614982B2 (en) * 2014-12-01 2020-04-07 Mitsubishi Electric Corporation Circuit closer and circuit closing system
CN112735903A (zh) * 2020-12-21 2021-04-30 西安交通大学 一种具备大电流开断能力的触发真空灭弧室及其工作方法
CN113130247A (zh) * 2019-12-30 2021-07-16 西安西电高压开关有限责任公司 一种组合式旁路开关
CN113130248A (zh) * 2019-12-30 2021-07-16 西安西电高压开关有限责任公司 一种组合式旁路开关
US11879927B2 (en) 2018-12-18 2024-01-23 S&C Electric Company Triggered vacuum gap fault detection methods and devices
US12205784B2 (en) 2020-09-29 2025-01-21 S&C Electric Company Triggered vacuum gap that controllably sustains a vacuum arc through current zeros

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2721434B1 (fr) * 1994-06-20 1996-08-02 Schneider Electric Sa Ampoule sous vide, notamment pour disjoncteur ou interrupteur électrique moyenne tension et interrupteur intégrant une telle ampoule.
GB2310760A (en) * 1996-02-27 1997-09-03 Gec Alsthom Ltd Vacuum switching device
US8228645B2 (en) * 2009-03-03 2012-07-24 General Electric Company Systems and methods for protecting a series capacitor bank

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA616849A (en) * 1961-03-21 E. Schofield Aldred Multiple spark gap switch
US3211866A (en) * 1963-02-05 1965-10-12 Gen Electric Vacuum type electric circuit interrupter with plural parallel-connected contact points
US3323002A (en) * 1965-12-28 1967-05-30 Gen Electric Triggered vacuum gap device having field emitting trigger assembly

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA616849A (en) * 1961-03-21 E. Schofield Aldred Multiple spark gap switch
US3211866A (en) * 1963-02-05 1965-10-12 Gen Electric Vacuum type electric circuit interrupter with plural parallel-connected contact points
US3323002A (en) * 1965-12-28 1967-05-30 Gen Electric Triggered vacuum gap device having field emitting trigger assembly

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3614532A (en) * 1970-06-01 1971-10-19 Gen Electric Triggered vacuum gap keep-alive circuit
US4041261A (en) * 1975-06-24 1977-08-09 General Electric Company High current capacity rod array vacuum arc discharge device
CN101086662B (zh) * 2006-06-09 2010-04-07 李玉敏 磁感应真空复式智能控制器
US10614982B2 (en) * 2014-12-01 2020-04-07 Mitsubishi Electric Corporation Circuit closer and circuit closing system
EP3561845A1 (de) * 2018-04-27 2019-10-30 Siemens Aktiengesellschaft Vakuum-leistungsschalterröhre
US11295913B2 (en) 2018-04-27 2022-04-05 Siemens Energy Global GmbH & Co. KG Vacuum circuit breaker
WO2019206732A1 (de) * 2018-04-27 2019-10-31 Siemens Aktiengesellschaft Vakuum-leistungsschalter
WO2019206570A1 (de) * 2018-04-27 2019-10-31 Siemens Aktiengesellschaft Netzbeeinflussungsanlage
EP3561846A1 (de) * 2018-04-27 2019-10-30 Siemens Aktiengesellschaft Vakuum-leistungsschalter
US11569045B2 (en) 2018-04-27 2023-01-31 Siemens Energy Global GmbH & Co. KG Grid influencing system
EP3561972A1 (de) * 2018-04-27 2019-10-30 Siemens Aktiengesellschaft Netzbeeinflussungsanlage
US11879927B2 (en) 2018-12-18 2024-01-23 S&C Electric Company Triggered vacuum gap fault detection methods and devices
CN113130248A (zh) * 2019-12-30 2021-07-16 西安西电高压开关有限责任公司 一种组合式旁路开关
CN113130248B (zh) * 2019-12-30 2022-08-19 西安西电高压开关有限责任公司 一种组合式旁路开关
CN113130247B (zh) * 2019-12-30 2022-11-22 西安西电高压开关有限责任公司 一种组合式旁路开关
CN113130247A (zh) * 2019-12-30 2021-07-16 西安西电高压开关有限责任公司 一种组合式旁路开关
US12205784B2 (en) 2020-09-29 2025-01-21 S&C Electric Company Triggered vacuum gap that controllably sustains a vacuum arc through current zeros
CN112735903A (zh) * 2020-12-21 2021-04-30 西安交通大学 一种具备大电流开断能力的触发真空灭弧室及其工作方法

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Publication number Publication date
JPS4712982B1 (de) 1972-04-20
GB1237466A (en) 1971-06-30
SE347386B (de) 1972-07-31
DE1806880A1 (de) 1969-09-11
CH476387A (de) 1969-07-31
FR1601758A (de) 1970-09-14

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