EP0354803A1 - Bistabiler magnetischer Betätiger und Schalter - Google Patents

Bistabiler magnetischer Betätiger und Schalter Download PDF

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Publication number
EP0354803A1
EP0354803A1 EP89308171A EP89308171A EP0354803A1 EP 0354803 A1 EP0354803 A1 EP 0354803A1 EP 89308171 A EP89308171 A EP 89308171A EP 89308171 A EP89308171 A EP 89308171A EP 0354803 A1 EP0354803 A1 EP 0354803A1
Authority
EP
European Patent Office
Prior art keywords
magnetic
actuator
armature
circuit
permanent magnet
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP89308171A
Other languages
English (en)
French (fr)
Inventor
Derek Kenworthy
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Alstom UK Ltd
Original Assignee
GEC Alsthom Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by GEC Alsthom Ltd filed Critical GEC Alsthom Ltd
Publication of EP0354803A1 publication Critical patent/EP0354803A1/de
Withdrawn legal-status Critical Current

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Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H51/00Electromagnetic relays
    • H01H51/22Polarised relays
    • H01H51/2209Polarised relays with rectilinearly movable armature
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01FMAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00Magnets
    • H01F7/06Electromagnets; Actuators including electromagnets
    • H01F7/08Electromagnets; Actuators including electromagnets with armatures
    • H01F7/16Rectilinearly-movable armatures
    • H01F7/1607Armatures entering the winding
    • H01F7/1615Armatures or stationary parts of magnetic circuit having permanent magnet
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H33/00High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/60Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
    • H01H33/66Vacuum switches
    • H01H33/666Operating arrangements
    • H01H33/6662Operating arrangements using bistable electromagnetic actuators, e.g. linear polarised electromagnetic actuators
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01FMAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00Magnets
    • H01F7/06Electromagnets; Actuators including electromagnets
    • H01F7/08Electromagnets; Actuators including electromagnets with armatures
    • H01F7/16Rectilinearly-movable armatures
    • H01F2007/1669Armatures actuated by current pulse, e.g. bistable actuators
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H51/00Electromagnetic relays
    • H01H51/22Polarised relays
    • H01H51/2209Polarised relays with rectilinearly movable armature
    • H01H2051/2218Polarised relays with rectilinearly movable armature having at least one movable permanent magnet
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H33/00High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/02Details
    • H01H33/027Integrated apparatus for measuring current or voltage

Definitions

  • This invention relates to a bistable magnetic actuator, and to an electric circuit breaker.
  • an electric circuit breaker whether it is a switch, an isolator, an autorecloser or some other device, it is necessary to have a mechanism that will open and close contacts in order to interrupt or close an electric circuit.
  • Conventional high-voltage circuit breakers include a complex, mechanical system for closing and tripping the switch contacts, and the need has arisen for an alternative mechanism capable of opening or closing the switch contacts on receipt of an electrical pulse, and in its static state of firmly holding the contacts in either of the set positions.
  • the invention provides a circuit-breaker comprising a circuit interrupter connected between two external terminals, a bistable magnetic actuator, having a permanent magnet for maintaining its state, connected via a mechanical linkage to operate the circuit interrupter, a capacitative charge store connected to power the actuator, means for recharging the charge store, and electronic control means connected to control the operation of the actuator in response to the current flowing between the terminals, at least the actuator, the charge store and the control means being housed in a common housing.
  • the actuator for the circuit breaker may be totally self-contained, and may even share the same gas-filled enclosure as the interrupter, which is preferably a vacuum interrupter.
  • the state of the interrupter is maintained by the permanent magnet, and the charge store preferably maintains for an appreciable time its capacity to power the magnetic actuator to change its state; preferably it maintains sufficient charge to permit several changes of state.
  • the store may be recharged by a long-life cell which will need replacement at intervals; preferably, however, it is recharged from the current flowing between the terminals, for example by a transformer connected to one of the terminals.
  • a bistable magnetic actuator comprises: a housing defined by two interlinked magnetic yokes, outer limbs of which constitute magnetic pole pieces, and inner limbs of which are mechanically connected; an armature axially reciprocable within the housing between the pole pieces and through the inner limbs on an axis passing through both limbs of both yokes, between two stable positions at each of which it forms a magnetic circuit with a respective magnetic pole piece and breaks the corresponding magnetic circuit with the other magnetic pole piece; an axially polarised magnet carried by the armature for generating the magnetic flux in the said magnetic circuits to hold the armature at one or other of the stable positions; and means for generating a transient magnetic field, in response to an actuation signal, simultaneously to reduce the flux in the said magnetic circuit without reducing significantly the flux within the permanent magnet, thereby to destabilise the armature without promoting demagnetisation of the permanent magnet, and to increase the flux between the armature and the other pole piece to attract the
  • An actuating member connected to the armature can then be caused to change position by the transient magnetic field, which may be generated by a stationary electromagnet coupled magnetically to the armature and to the pole pieces which preferably is activated by a capacitor-discharge circuit triggered by the actuation signal.
  • Movement of the actuating member may be imparted to a member to be operated, for example the moving contact of a circuit breaker, through any convenient form of mechanical link.
  • the actuator incorporates an armature AR comprising two cylindrical soft iron armature pieces 1, 2 having a permanent magnet 3 of disc form sandwiched betwen them, the armature being mounted coaxially at one end of a drive rod 4.
  • the drive rod 4 has a threaded end which serves to secure the elements 1, 2, 3 of the armature together.
  • the armature AR is contained within a housing formed by two interlinking yokes 5, 6 in the form of rectangular frames disposed at right angles to each other, the two inner, or linked limbs IL of the yokes 5, 6 being pierced by openings O which form bearings for the moving armature AR.
  • a tube 7 of non-magnetic material extends between the two inner limbs IL of the yokes around the central region of the armature, and serves to secure the yokes together.
  • the yokes 5, 6 are positioned so that the magnet 3 lies between the linked limbs IL of the yokes whether it is in one or other of its two terminal positions, with either one or other of the soft iron pole pieces 1, 2 in contact with the opposite, outer limb OL of the respective yoke.
  • the magnet 3 is magnetically polarised in the axial, longitudinal direction parallel to the reciprocating motion of the armature between end stops provided by the outer limbs OL.
  • the yoke 5 and the armature form a low reluctance magnetic circuit, so that the magnet 3 will produce a strong flux to hold the armature piece 1 against a fixed abutment face or end stop provided by the outer limb OL of the yoke 5.
  • Coils 8, 9 are disposed coaxially around respective ends of the armature AR, and if the coil 9 is energised to a level such that it will produce sufficient flux across the gap between the armature piece 2 and the outer limb OL of the yoke 6, and in a direction such that it assists the permanent magnet 3, then the outer limb OL of the yoke 5 will be starved of flux and the plunger P will transfer from left to right with no magnetic damage occurring to the permanent magnet 3, so that a strong retaining force will now hold the plunger at the right hand end of the actuator after the coil has been de-energised.
  • the process can be reversed by suitably energising the coil 8, and can be repeated indefinitely.
  • a relatively short pulse of current in the appropriate direction through the appropriate coil 8 or 9, as the case may be, will be sufficient to cause the plunger to move from one position to the other.
  • This short current pulse is provided by a capacitor-discharge circuit of conventional design, triggered by an electrical actuation signal from an external control circuit.
  • the drive arm 4 can be connected to the actuating mechanism of a circuit breaker for example to produce an opening or closing movement of the breaker contacts, depending upon the direction of movement of the plunger.
  • an actuator as above described can have a wide variety of other applications.
  • an auto-recloser circuit breaker principally for outdoor use but optionally for indoor applications, comprises, for each of three phases, a vacuum interrupter 22 housed in an EPDM rubber body 17.
  • a single kiosk 11 houses a bistable magnetic actuator 10 of the type described above, which operates all three vacuum interrupters 22 by way of a cross beam 25; in an alternative embodiment (not shown), the cross beam 25 is omitted and there is a magnetic actuator 10 for each phase.
  • the kiosk may rest on the ground, or else it may be mounted on a plinth or even a pole.
  • the interrupter contacts are maintained in either the closed or the open position by the magnetic actuator.
  • the fixed contact is connected to an upper line terminal 24 integral with a support casing, and the movable contact to an axially reciprocable transfer contact 18 which slides within a ring-shaped fixed contact 181 connected to a side-mounted terminal 20.
  • the side terminal 20 consists of a rod projecting transversely from an insulating bushing 21 forming part of the rubber body 17.
  • the body 17 has a number of rain sheds 171 moulded onto its outer surface to increase external creepage and flashover distances across the interrupter and from the interrupter 22 to the supporting kiosk 11 which is at earth potential.
  • the inner surface of the EPDM rubber body 17 is lined by a reinforced plastics tube 172 which provides mechanical strength and separates the EPDM rubber from a dielectric liquid or gaseous insulating medium 16 in which the internal parts are immersed.
  • the medium 16 is SF6 gas, supplied through a filling valve 13.
  • a protective current transformer core and toroidally wound secondary winding 19 surround the side-mounted line terminal 20, and are encapsulated in the bushing 21 integral with the rubber body 17.
  • the output from the current transformer is connected by a line 191, encapsulated in the rubber body 17, to the actuator assembly 10.
  • a single phase voltage transformer (not shown) is connected between the line terminal 20 and earth, or between the same line terminal 20 in different phases, and its output is used to supply power to charge storage capacitors in a pulsing unit (not shown) forming part of the magnetic actuator assembly 10, and an electronic control unit (not shown) for the actuator and pulsing unit which is also contained in the magnetic actuator assembly 10.
  • the control unit could be powered by a long-life cell.
  • the entire actuator may be immersed in an insulating gas to protect it from corrosive atmospheres.
  • the actuator 10 is coaxial with the vacuum interrupter, which it drives by way of a purely mechanical, direct linkage.
  • the linkage comprises an axial, insulating rod 15 connected at its upper end to the sliding contact 18 and at its lower end, via a lost motion device 12, to the actuator shaft.
  • the rod extends axially through the base of the rubber body 17 and through the roof of the kiosk 11, which is sealed against the underside of the base of the rubber body 17.
  • a sealing bellows 14 surrounds the lower portion of the rod 15 within the rubber body 17, but the bellows 14 is not required if the actuator is immersed in insulating gas.
  • the space within the kiosk may communicate with that within the rubber body 17, avoiding the need for the potentially leaky mechanical gas seals.
  • the control unit responds to a signal from the current transformer 19 indicative of either an over-current condition, a short circuit or an earth fault, to send an appropriate short pulse to activate the actuator.
  • the control unit includes a sequence timer for the auto-reclose function, which causes the interrupter contacts to reclose after a predetermined interval following circuit interruption. If the fault is not cured and the circuit is interrupted a second time, the circuit recloses after a longer predetermined interval; and so on, with progressively increasing intervals.
EP89308171A 1988-08-12 1989-08-11 Bistabiler magnetischer Betätiger und Schalter Withdrawn EP0354803A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8819166 1988-08-12
GB888819166A GB8819166D0 (en) 1988-08-12 1988-08-12 Magnetic actuator & permanent magnet

Publications (1)

Publication Number Publication Date
EP0354803A1 true EP0354803A1 (de) 1990-02-14

Family

ID=10642019

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89308171A Withdrawn EP0354803A1 (de) 1988-08-12 1989-08-11 Bistabiler magnetischer Betätiger und Schalter

Country Status (8)

Country Link
EP (1) EP0354803A1 (de)
JP (1) JPH03502021A (de)
CN (1) CN1040886A (de)
AU (2) AU4203389A (de)
GB (2) GB8819166D0 (de)
MT (1) MTP1046B (de)
WO (1) WO1990001788A1 (de)
ZA (1) ZA896108B (de)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4211155A1 (de) * 1992-03-31 1993-10-07 Siemens Ag Gasisolierte Schaltanlage mit einem mehrpoligen Vakuumschalter und einem mehrpoligen Lasttrennschalter
DE4211154A1 (de) * 1992-03-31 1993-10-07 Siemens Ag Gasisolierte Schaltanlage mit einem Vakuumschalter
DE4304921C1 (de) * 1993-02-18 1994-08-25 E I B S A Bistabiler magnetischer Antrieb für einen elektrischen Schalter
WO1995007542A1 (en) * 1993-09-11 1995-03-16 Brian Mckean Associates Ltd. Bistable magnetic actuator
EP0580285A3 (de) * 1992-07-20 1995-05-03 Gec Alsthom Ltd Selbsttätige Wiedereinschalter.
GB2297429A (en) * 1993-09-11 1996-07-31 Mckean Brian Ass Ltd Bistable magnetic actuator
EP0844637A2 (de) * 1996-11-22 1998-05-27 Siemens Aktiengesellschaft Elektrodynamischer Antrieb, insbesondere für Hochspannungsschaltgeräte
DE19709089A1 (de) * 1997-03-06 1998-09-10 Abb Patent Gmbh Permanentmagnetischer Antrieb für einen Schalter
DE19848551A1 (de) * 1998-10-21 2000-04-27 Abb Patent Gmbh Antrieb für das bewegliche Kontaktstück eines elektrischen Schalters
WO2001065581A1 (en) * 2000-03-02 2001-09-07 Cruise, Rupert, John A magnetic actuator
FR2847380A1 (fr) * 2002-11-15 2004-05-21 Mitsubishi Electric Corp Actionneur, procede pour sa fabrication et coupe-circuit equipe de l'actionneur.
DE10210321B4 (de) * 2001-04-24 2007-11-15 Tyco Electronics Amp Gmbh Bistabiler steuerbarer Leistungsschalter zum Schalten von grossen und kleinen Lasten
DE102008038900A1 (de) * 2008-08-13 2010-02-25 Thomas Magnete Gmbh Hubmagnet
US10825625B1 (en) 2019-06-07 2020-11-03 Smart Wires Inc. Kinetic actuator for vacuum interrupter
WO2022128514A1 (en) * 2020-12-18 2022-06-23 Assa Abloy Ab Actuator and lock device

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4002934A1 (de) * 1990-02-01 1991-08-08 Sachsenwerk Ag Vakuumschalter
KR940000049Y1 (ko) * 1991-12-13 1994-01-05 금성계전 주식회사 진공차단기의 아크방지용 개폐장치
DE10013549B4 (de) * 2000-03-20 2006-08-10 Fritz Driescher KG Spezialfabrik für Elektrizitätswerksbedarf GmbH & Co Anordnung eines Schalters
DE10308573A1 (de) * 2003-02-21 2004-09-09 Siemens Ag Elektrischer Schalter für Hoch- oder Mittelspannung
RU2249874C2 (ru) * 2003-03-26 2005-04-10 Общество С Ограниченной Ответственностью "Промышленная Группа Тэл Таврида Электрик" Вакуумный выключатель
DE102006042101B4 (de) 2006-09-07 2008-09-25 Switchcraft Europe Gmbh Vakuumschalter für Mittel- und Hochspannungen
DE102007028205A1 (de) * 2007-06-15 2008-12-24 Siemens Ag Schaltpol für ein Hochspannungsnetz
JP5606289B2 (ja) * 2010-11-17 2014-10-15 株式会社東芝 開閉器の状態検知装置および状態検知装置の取付方法
US9425012B2 (en) * 2011-08-29 2016-08-23 Mitsubishi Electric Corporation Electromagnetic operation device for vacuum circuit breaker
DE202011106188U1 (de) * 2011-09-30 2013-01-09 Fritz Driescher KG Spezialfabrik für Elektrizitätswerksbedarf GmbH & Co Schalterpoleinheit
CN103474287B (zh) * 2013-09-05 2015-09-30 北京交通大学 双动铁心永磁操动机构
KR101625481B1 (ko) * 2014-05-13 2016-05-31 엘에스산전 주식회사 고속스위치
US9514872B2 (en) 2014-12-19 2016-12-06 General Electric Company Electromagnetic actuator and method of use
GB2562069B (en) * 2017-05-03 2020-05-20 Tavrida Electric Holding Ag Improved vacuum circuit breaker
CN107731623A (zh) * 2017-11-29 2018-02-23 浙江华网电气有限公司 一种用于真空断路器的永磁操作机构

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1196418A (en) * 1966-09-26 1970-06-24 English Electric Co Ltd Improvements relating to Electro-Magnetic Devices
FR2141956A1 (de) * 1971-06-15 1973-01-26 Sperry Rand Corp
US4086645A (en) * 1977-02-18 1978-04-25 Electric Power Research Institute, Inc. Repulsion coil actuator for high speed high power circuits
DE3341625A1 (de) * 1982-11-25 1984-05-30 Aisin Seiki Solenoideinheit
US4568804A (en) * 1983-09-06 1986-02-04 Joslyn Mfg. And Supply Co. High voltage vacuum type circuit interrupter

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1196418A (en) * 1966-09-26 1970-06-24 English Electric Co Ltd Improvements relating to Electro-Magnetic Devices
FR2141956A1 (de) * 1971-06-15 1973-01-26 Sperry Rand Corp
US4086645A (en) * 1977-02-18 1978-04-25 Electric Power Research Institute, Inc. Repulsion coil actuator for high speed high power circuits
DE3341625A1 (de) * 1982-11-25 1984-05-30 Aisin Seiki Solenoideinheit
US4568804A (en) * 1983-09-06 1986-02-04 Joslyn Mfg. And Supply Co. High voltage vacuum type circuit interrupter

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4211154A1 (de) * 1992-03-31 1993-10-07 Siemens Ag Gasisolierte Schaltanlage mit einem Vakuumschalter
US5508486A (en) * 1992-03-31 1996-04-16 Siemens Aktiengesellschaft Gas-insulated switching unit with a multi-pole vacuum switch and a multi-pole circuit breaker
DE4211155A1 (de) * 1992-03-31 1993-10-07 Siemens Ag Gasisolierte Schaltanlage mit einem mehrpoligen Vakuumschalter und einem mehrpoligen Lasttrennschalter
EP0580285A3 (de) * 1992-07-20 1995-05-03 Gec Alsthom Ltd Selbsttätige Wiedereinschalter.
US5452172A (en) * 1992-07-20 1995-09-19 Lane; Stephen E. Auto-reclosers
DE4304921C1 (de) * 1993-02-18 1994-08-25 E I B S A Bistabiler magnetischer Antrieb für einen elektrischen Schalter
WO1995007542A1 (en) * 1993-09-11 1995-03-16 Brian Mckean Associates Ltd. Bistable magnetic actuator
GB2297429A (en) * 1993-09-11 1996-07-31 Mckean Brian Ass Ltd Bistable magnetic actuator
GB2297429B (en) * 1993-09-11 1997-07-09 Mckean Brian Ass Ltd Bistable magnetic actuator
US6009615A (en) * 1993-09-11 2000-01-04 Brian Mckean Associates Limited Method of manufacturing a bistable magnetic actuator
EP0844637A3 (de) * 1996-11-22 2000-11-22 Siemens Aktiengesellschaft Elektrodynamischer Antrieb, insbesondere für Hochspannungsschaltgeräte
EP0844637A2 (de) * 1996-11-22 1998-05-27 Siemens Aktiengesellschaft Elektrodynamischer Antrieb, insbesondere für Hochspannungsschaltgeräte
DE19709089A1 (de) * 1997-03-06 1998-09-10 Abb Patent Gmbh Permanentmagnetischer Antrieb für einen Schalter
DE19848551A1 (de) * 1998-10-21 2000-04-27 Abb Patent Gmbh Antrieb für das bewegliche Kontaktstück eines elektrischen Schalters
WO2001065581A1 (en) * 2000-03-02 2001-09-07 Cruise, Rupert, John A magnetic actuator
DE10210321B4 (de) * 2001-04-24 2007-11-15 Tyco Electronics Amp Gmbh Bistabiler steuerbarer Leistungsschalter zum Schalten von grossen und kleinen Lasten
FR2847380A1 (fr) * 2002-11-15 2004-05-21 Mitsubishi Electric Corp Actionneur, procede pour sa fabrication et coupe-circuit equipe de l'actionneur.
US6933827B2 (en) 2002-11-15 2005-08-23 Mitsubishi Denki Kabushiki Kaisha Actuator, method of manufacturing the actuator and circuit breaker provided with the actuator
DE102008038900A1 (de) * 2008-08-13 2010-02-25 Thomas Magnete Gmbh Hubmagnet
US10825625B1 (en) 2019-06-07 2020-11-03 Smart Wires Inc. Kinetic actuator for vacuum interrupter
WO2022128514A1 (en) * 2020-12-18 2022-06-23 Assa Abloy Ab Actuator and lock device

Also Published As

Publication number Publication date
JPH03502021A (ja) 1991-05-09
GB2223357A (en) 1990-04-04
ZA896108B (en) 1990-05-30
WO1990001788A1 (en) 1990-02-22
GB8819166D0 (en) 1988-09-14
AU4203389A (en) 1990-03-05
GB8918416D0 (en) 1989-09-20
MTP1046B (en) 1990-10-04
AU7635091A (en) 1991-08-08
CN1040886A (zh) 1990-03-28

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