US3641358A - Consecutive crowbar circuit breaker - Google Patents

Consecutive crowbar circuit breaker Download PDF

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Publication number
US3641358A
US3641358A US45147A US3641358DA US3641358A US 3641358 A US3641358 A US 3641358A US 45147 A US45147 A US 45147A US 3641358D A US3641358D A US 3641358DA US 3641358 A US3641358 A US 3641358A
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United States
Prior art keywords
interrupter
contacts
consecutive
electronic switch
switch
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Expired - Lifetime
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US45147A
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English (en)
Inventor
Kenneth T Lian
Willis F Long
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Raytheon Co
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Hughes Aircraft 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
    • H01H33/02—Details
    • H01H33/59—Circuit arrangements not adapted to a particular application of the switch and not otherwise provided for, e.g. for ensuring operation of the switch at a predetermined point in the AC cycle
    • H01H33/596—Circuit arrangements not adapted to a particular application of the switch and not otherwise provided for, e.g. for ensuring operation of the switch at a predetermined point in the AC cycle for interrupting DC
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/02—Details
    • H02H3/021—Details concerning the disconnection itself, e.g. at a particular instant, particularly at zero value of current, disconnection in a predetermined order

Definitions

  • a surge capacitor and its sup- [56] Ream cued pression resistance are serially connected in parallel around the second consecutive interrupter.
  • the UNITED STATES PATENTS transfer switch is opened and is deionized during conduction 3,534,226 10/ 1970 Lien ..317/1 1 C of the electronic switch.
  • Offswitching of the electronic switch 3,475,620 10/ 1969 Murray et a1.
  • ..307/136 causes current flow through the two parallel consecutive inter- 02 1/ 1964 Cable 317/11 X rupters with their series resistances to decrease circuit cur 3,237,030 2/1966 Cobum 307/136 X rent.
  • the multiphase transmission of electric power at a frequency corresponding to the generating source and the load equipment is widely used at present.
  • the employment of alternating current is desirable because it permits the use of transformers to change voltages from a value suitable for generation, to a value suitable for transmission, to a value suitable for distribution, and finally a value suitable for use.
  • the circuit breaker comprises a transfer switch in the DC line which normally carries the DC current.
  • Parallel to the transfer switch are an electronic switch, a first consecutive interrupter having a resistor in series therewith and a second consecutive interrupter having a resistance in series therewith.
  • the transfer switch, the electronic switch and the consecutive interrupters are controlled to operate in proper sequence upon fault detection.
  • a consecutive crowbar circuit breaker which is capable of breaking a high-voltage, high-current DC circuit. It is a further object to provide a circuit breaker which will permit the employment of DC transmission lines with circuit breakers therein to control circuit faults. It is another object to provide a circuit breaker having a single electronic switch therein, which electronic switch is closed during the opening steps of contacts in parallel thereto so that arcing is limited by the voltage drop on the electronic switch. It is still another object to provide a consecutive crowbar circuit breaker which consecutively opens contacts, with the contacts opening after the first one having resistance in series therewith for the absorption of circuit energy.
  • FIG. I is a schematic drawing of a high-voltage, high-current DC circuit having the consecutive crowbar circuit breaker of this invention connected therein.
  • FIG. 2 is a graph of circuit current vs time during the opening sequence of the circuit breaker of this invention.
  • FIG. 3 is a graph showing the voltage across the DC buses, during the sequence shown in FIG. 2.
  • FIG. 4 is a diagrammatic showing of the control equipment which controls the switches and interrupters.
  • FIG. 1 illustrates a high-voltage DC circuit with the consecutive crowbar circuit breaker of this invention incorporated therein.
  • the circuit is generally indicated at 10 and the circuit breaker is generally indicated at 12.
  • the circuit 10 comprises positive bus 14 and return bus 16. Connected therebetween is a high-voltage, high-current DC power source 18 which is conveniently illustrated as being a battery.
  • the power source usually comprises an engine or turbine driven multiphase AC generator which supplies power to transformers.
  • the transformers increase the voltage and supply the rectifiers which are connected between positive bus 14 and return bus 16.
  • the preferred example given in this specification is for a 400 megawatt system, because that power level appears to be appropriate for future use in power generation for adjacent urban environments. It is a level which might be used in underground transmission of power from nearby generating plants to urban areas.
  • the normal current is 1,000 amperes, as illustrated by the ordinate in FIG. 2 where each of the numerals indicates 1,000 amps.
  • FIG. 1 illustrates half of a system which, for purposes of example and illustration throughout this specifica tion, is a 400 mw. system.
  • Inductance 20 is serially connected with power source 18.
  • Inductance 20 represents the inductance of the entire circuit.
  • the circuit inductance limits the change in current with respect to time, and should the normal circuit inductance be too low, an additional inductor can be installed for smoothing and for limiting the rate of current increase in fault conditions.
  • the circuit inductance is one-half henry so that at the 200 kv. power source voltage the rate of change of current with respect to time upon occurrence of a fault is 400 amps per millisecond.
  • Load 26 can be any conventional commercial load or any special load which employs the power produced by the power source.
  • load 26 can include inverters, transformers and distribution equipment to the ultimate load.
  • Lines 28 and 30 represent transmission portions of the positive bus 14 and return bus 16, respectively, which transmit the power from the source to the load.
  • the circuit breaker 12 is preferably adjacent the source 18 and transmission over a distance occurs in lines 28 and 30.
  • Connection 32 with its switch 34, between lines 28and 30, represents a short circuit such as might occur at the input to load 26 or in the lines 28 and 30 leading thereto. Closure of the switch 34 represents an inadvertent short circuit and thus, connection 32 with its switch is schematically illustrative of other types of highly conductive electrical connections between lines 28 and 30.
  • Buses 36 and 38 are part of the circuit breaker l2 and are connected to positive bus 14 on opposite sides of transfer switch contacts 24. Connections between these buses 36 and 38 thus present parallel connections across transfer switch contacts 24. Electronic switch 40 is connected between these buses. The series combination of first consecutive interrupter 42' and its series resistance 44 are connected therebetween. Similarly, second consecutive interrupter 46 and its series resistor 48 are connected therebetween. If required, additional series combinations of consecutive interrupters and resistances can be connected therebetween for successive operations. Finally, suppression resistance 50 and capacitor 52 are serially connected together and are connected in parallel around second consecutive interrupter contacts 46.
  • fault sensor 22 senses a fault condition and is connected to control unit 54 which contains control circuitry to function as is hereinafter described.
  • the output of control unit 54 goes to transfer switch contact operator 56, electronic switch operator 58, first consecutive interrupter contact operator 60, and second consecutive interrupter contact operator 62.
  • Fault sensor 22 is any convenient and conventional fault sensor which is responsive to voltage between buses 14 and 16, is responsive to rate of change of the voltage between the buses, is responsive to current in bus 14 or is responsive to the change in current with respect to time in bus 14, or a combination of these signals.
  • Suitable fault sensors are shown in the following U. S. Pat. Nos: 3,353,17l; 3,419,791; 3,463,998; 3,471,784; 3,473,106; 3,475,653; 3,478,352; and 3,489,920. Any one or more of these can be employed as fault sensor 22.
  • the particular fault sensor is not critical to the invention and any conventional fault sensing means can be employed.
  • Transfer switch contact operator 56 and its contacts 24 are in the nature of those found in a conventional circuit breaker such as shown in U. S. Pat. No. 3,268,687 operating in SF to generate sufficient arc voltage.
  • the requirements are that the transfer switch contacts 24 be able to carry 1,000 amps when closed (the maximum current in the exemplified DC circuit of this specification), and to withstand without conduction the surge voltage of the circuit.
  • the surge voltage is selected to be 1.7 times the normal circuit voltage. With the normal circuit voltage at 200 kv., the surge voltage is 340 kv. in accordance with this example.
  • the transfer switch contacts 24 when opened and deionized, the transfer switch contacts 24 must be able to withstand an applied DC voltage of 340 kv.
  • the electronic switch 40 can be either a crossed field switching device or a liquid metal cathode-switching device, both of which are described in detail in patent application Ser. No. 681,632, filed Nov. 9, 1967, now U. S. Pat. No. 3,5 34,226, granted Oct. 13, I970.
  • the requirement of the electronic switch 40 is that it be able to turn on with voltage applied thereacross from a fairly small voltage value to a voltage value above the normal rated circuit voltage. In the present instance, on switching should be able to be accomplished for any value of voltage applied thereacross from its own minimum voltage drop to at least 220 kv., as seen in FIG. 3.
  • the electronic switch 40 must be capableof offswitching against this current.
  • the increase in voltage withstood by the switch 40 with respect to time should be at least 1.0 kv. per microsecond.
  • the crossed field switch and the liquid metal cathode switch of the above-identified patent are satisfactory for this purpose.
  • the electronic switch 40 may represent one or more serially connected electronic switches as described in the patent, to provide the desired standoff voltage for offswitching capability should the characteristics of electronic switch devices of commercial configuration so indicate.
  • Electronic switch operator 58 is connected to the electronic switch 40 in order to control its on and off switching. As is described in U. S. Pat. No. 3,534,226 the electronic switching devices can be controlled for on and off switching.
  • First consecutive interrupter contacts 42 and its operator 60 are. again in the nature of a circuit breaker such as is shown in U. S. Pat. No. 3,268,687, but for this use, a circuit breaker having that fast an operating speed is not necessary.
  • the contacts must be capable of withstanding 340 kv. when open and must be capable of conducting not more than 3,200 amps when closed.
  • the second consecutive interrupter with contact 46 and operator 62 is identical to the first consecutive interrupter. These interrupters share the 4,000 amp maximum currentand divide them in accordance with their series resistors 44 and 48.
  • Series resistors 44 and 48 are shown as being nonlinear re-- sistors. Such are preferable, for with nonlinear resistors the circuit breaker 12 of this invention is able to accomplish the circuit breaking function of the example with only the first and second consecutive interrupters 42 and 46. If linear resistors were employed instead of nonlinear resistors 44 and 48, at least three consecutive interrupters would be required.
  • Series resistors 44 and 48 are silicon carbide devices. These resistors divide the maximum current between contacts 42 and 46 on the basis of 2,700 and 1,300 amps.
  • Surge capacitor 52 is of conventional oil filled character and has a value of about 2.0 microfarads in the example of the specification. It is capable of withstanding the 340 kv. voltage to arrest the final voltage surge. Its surge suppression resistor 50 has a value of ohms and is capable of carrying 700 amps in surge suppression duty.
  • power source 18 is supplying l,000 amps of current through inductance 20, fault sensor 22, closed contacts 24 of the transfer switch and through load 26.
  • the voltage drop across the load is the nominal circuit value of 200 kv.
  • the contacts 42 and 46 of the first and second consecutive interrupters are closed.
  • the electronic switch 40 is in standby condition so that when a voltage is applied thereacross, it will be conductive. This is the state of affairs illustrated in FIGS. 2 and 3 along the abscissa from the intersection to time point a.
  • a fault appears short-circuiting lines 28 and 30, as represented by the closing of switch 34.
  • This fault causes a drop in voltage to near zero, and an increase in current as limited by the value of inductance 20.
  • Current increases at the rate of 400 amps per ms., as previously described.
  • Sensor 22 senses the increase or the rate of increase of current, or the decrease or the rate of decrease of voltage between buses, or the combination of these signals to determine that a fault has occurred. Such determination occurs at point b along the abscissa of the graphs of FIGS. 2 and 3.
  • This sensing by sensor 22 causes control unit 54 to signal operator 56 to open transfer switch contacts 24. These switch contacts open, and as they open an arc is drawn and voltage drop occurs thereacross.
  • the electronic switch 40 is in its standby condition wherein it is ready to conduct as soon as there is sufficient voltage thereacross.
  • the opening of contacts 24 and the voltage drop in the are thereacross provides this sufficient conduction voltage for electronic switch 40.
  • an appropriate voltage drop is 500 v.
  • the voltage drop across the electronic switch is indicated along the abscissa in FIG. 3 between b and c.
  • the voltage drop of a liquid metal are switching device would be somewhat lower.
  • control unit 54 operates electronic switch operator 58 to turn off the electric switch 40. This causes the voltage surge at point c since all current must pass through the paralleled first and second consecutive interrupter contacts 42 and 46, and their respective resistances. The value of these resistances is such as to cause a reduction in current from time point c to point d.
  • control unit 54 causes the first consecutive interrupter contacts 42 to be opened and again causes conduction of electronic switch 40 for a short time period. Since the contacts are deionized only against the small voltage drop across the conducting electronic switch 40, arcing quickly stops. As soon as the electronic switch starts conducting, current stops flowing in interrupter 42.
  • control unit 54 again causes the tumofi of electronic switch 40 to bring the voltage back up to its peak point, as illustrated at time d in FIG. 3.
  • the current is forced to flow through resistor 46 and second consecutive interrupter contacts 46.
  • the current is reduced to a point where it can be accommodated by surge capacitor 52 with its surge suppression resistor 50. This capability occurs at point e whereupon control unit 54 causes opening of second consecutive interrupter contact 46 and the short period of conduction of electronic switch 40.
  • electronic switch 40 is again turned off by the control unit 54 and the balance of the surge current in the system is directed into surge capacitor 52 and resistor 50.
  • the circuit breaker 12 can be employed as a main switch for opening the bus, either at the source and/or load end thereof. Furthermore, it can be employed as a switch for a branch line on a transmission line. Thus, the circuit breaker I2 is a special purpose application of a generic switch.
  • a DC circuit interrupter comprising a DC electric line and transfer switch, contacts connected in said DC electric line to open said DC electric line;
  • control means connected to operate said transfer switch contacts, said electronic switch, said first consecutive interrupter contacts and said second consecutive interrupter contacts for successive opening of said transfer tronic switch to be conductive during each of the successive openings and nonconductive intermediate the openings so that said electronic switch is conductive during opening of said contacts to stop current flow through said contacts and permit them to deionize.
  • fault sensing means is connected to said DC line to detect a fault therein, said fault sensing means being connected to said control means so that upon the sensing of a fault in said DC line, said control means causes said interrupter to open.
  • fault sensing means is connected to said DC line to detect a fault therein, said fault sensing means being connected to said control means so that upon the sensing of a fault in said DC line, said control means causes said interrupter to open.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Driving Mechanisms And Operating Circuits Of Arc-Extinguishing High-Tension Switches (AREA)
  • Arc-Extinguishing Devices That Are Switches (AREA)
  • Switches That Are Operated By Magnetic Or Electric Fields (AREA)
US45147A 1970-06-10 1970-06-10 Consecutive crowbar circuit breaker Expired - Lifetime US3641358A (en)

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Application Number Priority Date Filing Date Title
US4514770A 1970-06-10 1970-06-10

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US3641358A true US3641358A (en) 1972-02-08

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US45147A Expired - Lifetime US3641358A (en) 1970-06-10 1970-06-10 Consecutive crowbar circuit breaker

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US (1) US3641358A (enrdf_load_stackoverflow)
JP (1) JPS5228991B1 (enrdf_load_stackoverflow)
CA (1) CA921602A (enrdf_load_stackoverflow)
DE (1) DE2127770C3 (enrdf_load_stackoverflow)
FR (1) FR2094171B1 (enrdf_load_stackoverflow)
GB (1) GB1334171A (enrdf_load_stackoverflow)
SE (1) SE381366B (enrdf_load_stackoverflow)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3777178A (en) * 1971-09-30 1973-12-04 J Gratzmuller Interrupter device for high voltage direct current
US3786310A (en) * 1973-03-29 1974-01-15 Hughes Aircraft Co Hybrid dc circuit breaker
US4652963A (en) * 1984-03-07 1987-03-24 Asea Aktiebolag Series capacitor equipment
US6075684A (en) * 1998-03-23 2000-06-13 Electric Boat Corporation Method and arrangement for direct current circuit interruption
WO2006026545A3 (en) * 2004-08-27 2006-08-31 Carter Group Inc Motor relay arc protection apparatus and methods
US20080259516A1 (en) * 2007-04-18 2008-10-23 Kuo Han Electronic Co., Ltd. Protector for instant driving circuit of electric device
US20100147869A1 (en) * 2008-12-12 2010-06-17 The Stanley Works Blade dispenser
US20100220431A1 (en) * 2008-09-15 2010-09-02 Viper Subsea Limited Subsea Protection Device
WO2021138207A1 (en) * 2019-12-31 2021-07-08 Emera Technologies LLC Power distribution systems and methods
EP3913804A1 (de) * 2020-05-18 2021-11-24 Ellenberger & Poensgen GmbH Überspannungsschutz
US11859878B2 (en) 2018-10-23 2024-01-02 Carrier Corporation Electrocaloric heat transfer system

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU1712977A1 (ru) * 1989-02-13 1992-02-15 Всесоюзный Научно-Исследовательский Проектно-Конструкторский И Технологический Институт Взрывозащищенного И Рудничного Электрооборудования Способ коммутации электрической цепи
GB201018004D0 (en) 2010-10-25 2010-12-08 Trend Marine Products Ltd An improved closure means
CN103280763B (zh) * 2013-02-27 2016-12-28 国网智能电网研究院 一种直流断路器及其实现方法

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3118102A (en) * 1960-12-14 1964-01-14 Ledex Inc Diode rectifier with overvoltage protection
US3237030A (en) * 1962-09-28 1966-02-22 Dynamics Controls Corp Radio noise-free switch
US3249810A (en) * 1962-11-20 1966-05-03 Westinghouse Electric Corp Circuit interrupting apparatus
US3401303A (en) * 1965-11-23 1968-09-10 Westinghouse Electric Corp Circuit closing and interrupting apparatus
US3430063A (en) * 1966-09-30 1969-02-25 Nasa Solid state switch
US3448287A (en) * 1965-09-29 1969-06-03 Bbc Brown Boveri & Cie Electrical switching arrangement with multiple interruption
US3475620A (en) * 1967-12-29 1969-10-28 Atomic Energy Commission Heavy current arcing switch
US3476978A (en) * 1967-12-06 1969-11-04 Gen Electric Circuit interrupting means for a high voltage d-c system
US3515940A (en) * 1968-02-21 1970-06-02 Gen Electric Parallel-assisted circuit interrupting device
US3522472A (en) * 1965-05-26 1970-08-04 Asea Ab Direct current breaker
US3534226A (en) * 1967-11-09 1970-10-13 Hughes Aircraft Co Sequential switching circuit breaker for high power ac or dc power transmission circuits

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH237265A (de) * 1943-07-15 1945-04-15 Bbc Brown Boveri & Cie Schalteinrichtung zum Abschalten von hochgespanntem Gleichstrom.
US2546818A (en) * 1946-04-23 1951-03-27 Bell Telephone Labor Inc Electric switch contact protection

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3118102A (en) * 1960-12-14 1964-01-14 Ledex Inc Diode rectifier with overvoltage protection
US3237030A (en) * 1962-09-28 1966-02-22 Dynamics Controls Corp Radio noise-free switch
US3249810A (en) * 1962-11-20 1966-05-03 Westinghouse Electric Corp Circuit interrupting apparatus
US3522472A (en) * 1965-05-26 1970-08-04 Asea Ab Direct current breaker
US3448287A (en) * 1965-09-29 1969-06-03 Bbc Brown Boveri & Cie Electrical switching arrangement with multiple interruption
US3401303A (en) * 1965-11-23 1968-09-10 Westinghouse Electric Corp Circuit closing and interrupting apparatus
US3430063A (en) * 1966-09-30 1969-02-25 Nasa Solid state switch
US3534226A (en) * 1967-11-09 1970-10-13 Hughes Aircraft Co Sequential switching circuit breaker for high power ac or dc power transmission circuits
US3476978A (en) * 1967-12-06 1969-11-04 Gen Electric Circuit interrupting means for a high voltage d-c system
US3475620A (en) * 1967-12-29 1969-10-28 Atomic Energy Commission Heavy current arcing switch
US3515940A (en) * 1968-02-21 1970-06-02 Gen Electric Parallel-assisted circuit interrupting device

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3777178A (en) * 1971-09-30 1973-12-04 J Gratzmuller Interrupter device for high voltage direct current
US3786310A (en) * 1973-03-29 1974-01-15 Hughes Aircraft Co Hybrid dc circuit breaker
US4652963A (en) * 1984-03-07 1987-03-24 Asea Aktiebolag Series capacitor equipment
US6075684A (en) * 1998-03-23 2000-06-13 Electric Boat Corporation Method and arrangement for direct current circuit interruption
WO2006026545A3 (en) * 2004-08-27 2006-08-31 Carter Group Inc Motor relay arc protection apparatus and methods
US7561401B2 (en) * 2007-04-18 2009-07-14 Kuo Han Electronic Co., Ltd. Circuit protector for electric device
US20080259516A1 (en) * 2007-04-18 2008-10-23 Kuo Han Electronic Co., Ltd. Protector for instant driving circuit of electric device
US20100220431A1 (en) * 2008-09-15 2010-09-02 Viper Subsea Limited Subsea Protection Device
US20100147869A1 (en) * 2008-12-12 2010-06-17 The Stanley Works Blade dispenser
US11859878B2 (en) 2018-10-23 2024-01-02 Carrier Corporation Electrocaloric heat transfer system
WO2021138207A1 (en) * 2019-12-31 2021-07-08 Emera Technologies LLC Power distribution systems and methods
CN114902524A (zh) * 2019-12-31 2022-08-12 埃默拉技术有限责任公司 电力分布系统和方法
EP3913804A1 (de) * 2020-05-18 2021-11-24 Ellenberger & Poensgen GmbH Überspannungsschutz

Also Published As

Publication number Publication date
DE2127770B2 (de) 1973-11-15
CA921602A (en) 1973-02-20
GB1334171A (en) 1973-10-17
FR2094171A1 (enrdf_load_stackoverflow) 1972-02-04
DE2127770A1 (de) 1971-12-16
DE2127770C3 (de) 1974-07-04
FR2094171B1 (enrdf_load_stackoverflow) 1974-08-19
JPS5228991B1 (enrdf_load_stackoverflow) 1977-07-29
SE381366B (sv) 1975-12-01

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