US2958808A - Electrical arc suppressor - Google Patents

Electrical arc suppressor Download PDF

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Publication number
US2958808A
US2958808A US652543A US65254357A US2958808A US 2958808 A US2958808 A US 2958808A US 652543 A US652543 A US 652543A US 65254357 A US65254357 A US 65254357A US 2958808 A US2958808 A US 2958808A
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United States
Prior art keywords
contacts
source
impedance device
circuit
asymmetric
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Expired - Lifetime
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US652543A
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English (en)
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Miller William
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AMF Inc
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AMF Inc
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Priority to FR1193942D priority Critical patent/FR1193942A/fr
Application filed by AMF Inc filed Critical AMF Inc
Priority to US652543A priority patent/US2958808A/en
Priority to GB8005/58A priority patent/GB849240A/en
Priority to DEA29132A priority patent/DE1160059B/de
Application granted granted Critical
Publication of US2958808A publication Critical patent/US2958808A/en
Anticipated expiration legal-status Critical
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
    • H01H9/54—Circuit arrangements not adapted to a particular application of the switching device and for which no provision exists elsewhere
    • H01H9/541—Contacts shunted by semiconductor devices

Definitions

  • FIG. 2 ELECTRICAL ARC SUPPRESSOR Filed April 12, 1957 FIG. I FIG. 2
  • FIG. 4 32 0.0. T0 A.C. RECTIFIER 30/ CONVERTER j FILTER ⁇ 34 I l 72 I LOAD FIG. 5
  • the ideal solution is to provide a zero impedance path shunting the contacts at the instant of opening and when the distance between the contacts is increased to a point where it will no longer sustain an arc at any practical voltage, the value of the impedance should rapidly change from zero to an infinite value.
  • the zero impedance is designed to short-circuit the voltage appearing across the contacts at the instant of opening and during the period when the contacts are separat ing, while the infinite resistance should provide an open circuit when the contacts are disengaged.
  • One form of arc suppression is to parallel the contacts with a resistor of appropriate size.
  • Appropriate resistor size may be chosen for practically any set of circuit breaking conditions but for circuits having any appreciable current magnitude, the resistor which must be shunted across the contacts is of such low value that there is an undesirably large current flow after the contacts are open.
  • the resistor connected across the contacts is of too high a value, little or no suppression results.
  • the ideal circuit for are suppression would be the shunting of the contacts with a low or zero impedance before and immediately after contacts have begun to open and then switching, without use of any further contacts, the resistance from one of a low value to one of an infinitely high value, after the main contacts have opened.
  • a practical embodiment of the ideal arc suppression circuit is provided by connecting in parallel with the contacts whose arc is to be suppressed a circuit comprising, in series, an asymmetric impedance device of the type which exhibits minority carrier storage, and a source of electrical potential for biasing the asymmetrical impedance in a forward current direction.
  • a circuit comprising, in series, an asymmetric impedance device of the type which exhibits minority carrier storage, and a source of electrical potential for biasing the asymmetrical impedance in a forward current direction.
  • the asymmetric impedance and bias source are short-circuited so that the asymmetric impedance is biased in a forward direction.
  • the impedance of the series circuit is very low due to the time period required for the asymmetric impedance device to reach an equilibrium state of reverse bias.
  • the transition from the forward to equilibrium reverse biasing condition is not instantaneous because of the phenomenon of minority carrier storage.
  • the asymmetric impedance device is biased highly in a reverse or high impedance direction by the normal load voltage source which is applied directly across the series circuit because of the open contacts.
  • Conductivity in certain types of asymmetric impedance devices is associated with two types of electrical carriers, poles and electrons. In such material both types of carriers are present but one is in excess of the other. Those in excess are known as majority carriers while those in the minority are known as minority carriers. In that type of material designated as N, the majority carriers are electrons and the minority carriers are holes; in that type of material generally designated as P, majority carriers are holes and minority carriers are electrons.
  • N the majority carriers are electrons and the minority carriers are holes
  • P majority carriers are holes and minority carriers are electrons.
  • the flow of majority carriers has associated therewith a flow of minority carriers in the opposite direction. Minority carriers tend to recombine with the majority carriers and the probability of recombination per unit time is related to the minority carrier lifetime.
  • Minority carriers tend to recombine with the majority carriers and the probability of recombination per unit time is related to the minority carrier lifetime.
  • an asymmetric impedance device of the type described has been biased or is conducting in a forward direction, that is, in a direction of majority carrier flow, and is suddenly biased negative, the influx of minority carriers is cut oif.
  • reverse bias immediately after reverse bias is applied, there is a large number of excess minority carriers present which permit a large reverse current to flow through the impedance device and its forward biasing source and last for a period of time of the order of the lifetime of the minority carriers.
  • the number of minority carriers drops back to its equilibrium value which is many orders of magnitude smaller than the number present during forward current flow.
  • the current which flows in the reverse direction is of the order of microamperes or less, depending upon the type of material which com rises the asymmetric impedance.
  • the reverse impedance of the asymmetric impedance device then varies from an order of magnitude in ohms to megohms within a few microseconds. Accordingly, it will be seen that the reverse transient conditions in an asymmetric impedance device of the type herein described can be used to provide a low resistance across the contacts as they are opened which rapidly changes to a high resistance as the minority carriers recombine.
  • heavy load current switching is substantially performed by the asymmetric impedance device in shunt across the contacts rather than by the contacts themselves.
  • Fig. 1 is a schematic diagram of a circuit embodying the principles of the invention.
  • Fig. 2 is a modification of the embodiment of the invention shown in Fig. 1.
  • Fig. 3 is another embodiment of the invention particularly adapted for use in alternating current circuits.
  • Fig. 4 is a schematic diagram, partially in block form, showing a further modification of the embodiment of the invention shown in Fig. 1.
  • Fig. 5 is a schematic diagram of a modification of the embodiment of the invention shown in Fig. 3.
  • a source of electrical potential 10 which may be a battery or any other suitable source of voltage connected in series with a pair of switch contacts 12 and a load 14.
  • Load 14 may beany type of electrical load and may be either resistive, capacitive or inductive in nature.
  • Contacts 12 may be contacts associated with a manually operated switch or an electrically energized relay or any other type of circuit-breaking device, Well-known in the art.
  • Across contacts 12 is'connected a series circuit comprising asymmetric impedance device 16 and associated source of biasing potential18 which, for purpose of illustration, is shown as a battery.
  • the value of potential for battery 18 is selected to provide a flow of current of such a magnitude in the forward direction through asymmetric impedance device 16 that the resistance of device 16 is very low in comparison with the load impedance.
  • potential source 18 generally has only a fractional value of that of potential source 11
  • Asymmetric impedance device 16 may be any suitable type of asymmetric impedance which is capable of exhibiting minority carrier storage. The choice of a suitable asymmetric device will depend upon the potential of the voltage source 111, the nature of load 14, and the rapidity with which shifting of asymmetric impedance device 16 from a forward to an equilibrium reverse state is desired.
  • Typical asymmetric impedance devices which may be used are point contact semi-conductor diodes or P-N junction diodes of the type which usually include silicon or germanium as the major semi-conductor material.
  • the recovery time of device 16 and, thus, the substantially zero impedance period existmg after contacts 12 have opened may be varied selectively by changing the value of bias source 18.
  • the forward current through asymmetric impedance device 16 is very small so that the drain on bias source 18 is negligible.
  • the forward current may rise to a value sufiicient to cause moderately heavy drain on bias source 18. Therefore, in accordance with the modificat on shown in Fig. 2, an additionalpair of contacts 20 for disconnecting the bias source may be connected in series with asymmetric impedance device 16 and bias source 18, and operatively ganged with contacts of switch 12.
  • switch 20 close just before the contacts of switch 12 open in order to allow the forward bias from source 13 to be applied to the device 16 for a short interval prior to the opening of contacts 12.
  • switch 20 may be of the type which remains closed while switch 12 is opening but open with the final opening movements of switch 12 after the need for the arc suppression is completed. In this manner not even a reverse current of a few microamperes would flow in the circuit.
  • FIG. 3 there is shown another embodiment of the novel arc suppressor circuit which provides for the dis- 7 will be noted that the bridge circuit is so arranged that when switch 12 is closed, alternating current is free to flow in both directions through the circuit, but when switch 12 is opened, the flow of current is shut ofi by the opposed polarity of the rectifiers for each A.C. half-cycle. Since switch 12 interrupts a current always flowing in the same direction, the arc resulting from the interruption of this current is suppressed effectively in the same manner as described above.
  • Asymmetric impedance device 16 is biased in a forward direction by bias source 18 in the manner as described heretofore.
  • Diode rectifier units 26 may be any diode unit of the type well-known in the art and having suitable characteristics for the particular application to which the circuit is put, and having appropriate load ratings.
  • Figure 4 is a modification of the invention in which only passive elements are used in the arc suppression portion of the circuit. Such an arrangement is particularly suitable where long, unattended operation of the invention is desired withou t ha ving to replace the source of forward biasing voltage 18, as is eventually necessary when a conventional, electrolytic type battery is used for source 18.
  • a resistor 28 is connected in the main load circuit and has an ohmic value suitable for providing a source of DC. voltage thereacross for energizing DC. to A.C. converter 30.
  • the converter maybe any of the known DC. to A.C. translating devices such as an electronic valve oscillator, a transistor oscillator or a mechanical type vibrator.
  • the AC. output of the oscillator or vibrator comprising converter 30 is transmitted through a coupling transformer 32 to a conventional rectifier-filter 34 which rectifies and filters the AC. output of transformer 32 in the usual manner and provides a DC. output of a value selected to suitably bias asymmetric impedance 1 6 in the forward direction.
  • Transformer 32 isolates asymmetric impedance device 16 from resistor 23 and the main load circuit when switch 12 is opened to prevent a by-pass circuit around asymmetric impedance device 16 from forming and re-energizing the load 14. As only passive elements are used to provide the forward biasing source, the entire arc suppressor circuit is deenergized when switch 12 is opened.
  • Fig. 4 may be further modified as shown in Fig. 5 when the passive element, forward biasing feature is utilized in conjunction with an AC. load voltage source 22.
  • Converter 31 is omitted and transformer 32 is connected in series with the load circuit.
  • Rectifier-filter 34 connected to transformer 32 provides the forward bias voltage for asymmetric impedance 16. The remainder of the circuit is the same as that shown in Fig. 3 and described hereinabove.
  • An arc suppressor comprising a source of electrical potential, a load connected to said source of potential, a pair of movable contacts serially connected between said source and said load, an auxiliary circuit including an asymmetric impedance device exhibiting minority carrier storage connected in parallel across said contacts, said auxiliary circuit including means for causing current to flow through said asymmetric impedance device in a forward direction for at least a portion of the period when said contacts are closed, said source of potential being sufficient to bias said asymmetric impedance device in a reverse direction when said contacts are open.
  • a pair of movable electrical terminals a source of electrical potential connected to said terminals, an asymmetric impedance device exhibiting minority carrier storage connected to one of said terminals, a source of bias potential serially connected to said asymmetric impedance device and said other terminal and adapted to bias said asymmetric impedance device in a forward direction when said terminals are in engagement with each other, said source of electrical potential being sufficient to bias said asymmetric impedance device in a reverse direction when said terminals are disengaged.
  • a pair of movable electrical terminals a source of electrical potential connected to said terminals, an asymmetric impedance device exhibiting minority carrier storage connected to one of said terminals, a source of bias potential serially connected to said asymmetric impedance device and said other terminal and adapted to bias said asymmetric impedance device in a forward direction when said terminals are in engagement with each other, said source of electrical potential being sufiicient to bias said asymmetric impedance device in a reverse direction when said terminals are disengaged, and a normally closed switch connected in series with said source of bias potential and said asymmetric impedance device and operative in response to the closing of said terminals to disconnect said bias source from said asymmetric impedance device.
  • An arc suppressor circuit comprising a source of A.C. electrical potential, a load connected to said source of A.C. potential, a pair of movable contacts serially connected between said source and said load operative to form a closed circuit, means connected in said closed circuit operative to permit only a D.C. potential to appear across said contacts when said contacts are opened, an auxiliary circuit including an asymmetric impedance device exhibiting minority carrier storage connected in parallel across said contacts, said auxiliary circuit including means for causing current to flow through said asymmetric impedance device in a forward direction for at least a portion of the period when said contacts are closed, the potential appearing across said contacts when open being sufficient to bias said asymmetric impedance device in a reverse direction.
  • said means for allowing only a D.C. potential to appear across said contacts includes a bridge rectifier circuit having two pairs of arm junction terminals, one of said pairs being 6 connected between said A.C. source and said load, and said contacts are connected between the remaining pair of said arm junction terminals.
  • said means for causing current to flow through said asymmetric impedance device in a forward direction includes a transformer having an output winding and an input winding serially connected between said source and said load, means connected to said output winding for translating A.C. voltage into D.C. voltage, and connections between said. asymmetric impedance device and said voltage translating means for applying a forward biasing voltage to said asymmetric impedance device.
  • a pair of movable electrical terminals a source of D.C. electrical potential connected to said terminals, an asymmetric impedance device exhibiting minority carrier storage connected to one of said terminals, a source of bias potential serially connected to said asymmetric impedance device and said other terminal and adapted to bias said asymmetric impedance device in a forward direction when said terminals are in engagement with each other, said source of forward bias potential including a D.C. to A.C. converter, means connected between said source of electrical potential and said terminals for energizing said converter with a selected D.C. voltage, means for detecting and filtering the output of said converter to provide a forward D.C. bias for said asymmetric impedance device, said source of D.C. electrical potential being sufiicient to bias said asymmetric impedance device in a reverse direction when said terminals are disengaged.
  • An arc suppressor comprising a source of electrical potential, a load connected to said source of potential, a pair of movable contacts serially connected between said source and said load, an auxiliary circuit including an asymmetric impedance device exhibiting minority carrier storage connected in parallel across said contacts, said auxiliary circuit including means for causing current to flow through said asymmetric impedance device in a forward direction for at least a portion of the period when said contacts are closed, said auxiliary circuit means including means responsive to current flowing in said load for generating a first voltage, means connected to said first voltage generating means for generating a second selected voltage representative of said first voltage, means for isolating said second voltage from said first voltage, means connected to said auxiliary circuit for applying said second voltage to said asymmetric impedance device to bias said impedance device in a forward direction, said source of potential being sufficient to bias said asymmetric impedance device in a reverse direction when said contacts are open.

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US652543A 1957-04-12 1957-04-12 Electrical arc suppressor Expired - Lifetime US2958808A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
FR1193942D FR1193942A (da) 1957-04-12
US652543A US2958808A (en) 1957-04-12 1957-04-12 Electrical arc suppressor
GB8005/58A GB849240A (en) 1957-04-12 1958-03-12 Electric switching arc suppression circuit
DEA29132A DE1160059B (de) 1957-04-12 1958-03-26 Anordnung zur Unterdrueckung von Lichtboegen

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US652543A US2958808A (en) 1957-04-12 1957-04-12 Electrical arc suppressor

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US2958808A true US2958808A (en) 1960-11-01

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DE (1) DE1160059B (da)
FR (1) FR1193942A (da)
GB (1) GB849240A (da)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3165640A (en) * 1960-12-15 1965-01-12 North American Aviation Inc D. c. controlled semiconductor switch for a. c. current
US3699402A (en) * 1970-07-27 1972-10-17 Gen Electric Hybrid circuit power module
US4249223A (en) * 1978-12-01 1981-02-03 Westinghouse Electric Corp. High voltage DC contactor with solid state arc quenching
US4276484A (en) * 1979-09-10 1981-06-30 Riveros Carlos A Method and apparatus for controlling current in inductive loads such as large diameter coils
US4296449A (en) * 1979-08-27 1981-10-20 General Electric Company Relay switching apparatus
USRE33314E (en) * 1984-10-10 1990-08-28 Mars Incorporated Vending machine power switching apparatus
US5536980A (en) * 1992-11-19 1996-07-16 Texas Instruments Incorporated High voltage, high current switching apparatus
WO2013131557A1 (en) * 2012-03-06 2013-09-12 Abb Technology Ag Arc-jump circuit breaker and method of circuit breaking
US8619395B2 (en) 2010-03-12 2013-12-31 Arc Suppression Technologies, Llc Two terminal arc suppressor

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH444938A (de) * 1966-03-29 1967-10-15 Bbc Brown Boveri & Cie Druckgasschalter mit Stift und Gegenkontakt

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE517083C (de) * 1929-08-03 1931-01-31 Siemens Schuckertwerke Akt Ges Einrichtung zur Unterbrechung von Wechselstroemen
DE611317C (de) * 1935-03-26 Aeg Anordnung zum Unterbrechen von elektrischen Stromkreisen usw.
DE613832C (de) * 1935-05-27 Siemens Schuckertwerke Akt Ges Anordnung zum Abschalten eines induktiven Widerstandes in einem Gleichstromkreis
US2011395A (en) * 1933-08-12 1935-08-13 Gen Electric Electric circuit
DE638981C (de) * 1932-07-05 1936-11-26 Siemens Schuckertwerke Akt Ges Anordnung zum Ausschalten von Wechselstromkreisen
FR874152A (da) * 1942-08-05
US2782345A (en) * 1952-03-22 1957-02-19 Fkg Fritz Kesselring Geratebau Alternating current switching device
US2791739A (en) * 1954-05-20 1957-05-07 Philips Corp Circuit arrangement for converting a lower d. c. voltage into a higher d. c. voltage
US2859400A (en) * 1952-03-22 1958-11-04 Fkg Fritz Kesselring Geratebau Alternating current switching device
US2873419A (en) * 1955-09-22 1959-02-10 Bbc Brown Boveri & Cie Arc-back prevention circuit

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR759031A (fr) * 1933-07-31 1934-01-27 Dispositif pour supprimer les étincelles des interrupteurs électriques
GB663898A (en) * 1949-05-31 1951-12-27 Westinghouse Brake & Signal Improvements relating to methods of suppressing arcing at contacts breaking an inductive circuit
NL153566C (da) * 1949-05-31
CH319034A (de) * 1954-03-12 1957-01-31 Fkg Ag Schalteinrichtung, insbesondere für periodisches Schalten

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE611317C (de) * 1935-03-26 Aeg Anordnung zum Unterbrechen von elektrischen Stromkreisen usw.
DE613832C (de) * 1935-05-27 Siemens Schuckertwerke Akt Ges Anordnung zum Abschalten eines induktiven Widerstandes in einem Gleichstromkreis
FR874152A (da) * 1942-08-05
DE517083C (de) * 1929-08-03 1931-01-31 Siemens Schuckertwerke Akt Ges Einrichtung zur Unterbrechung von Wechselstroemen
DE638981C (de) * 1932-07-05 1936-11-26 Siemens Schuckertwerke Akt Ges Anordnung zum Ausschalten von Wechselstromkreisen
US2011395A (en) * 1933-08-12 1935-08-13 Gen Electric Electric circuit
US2782345A (en) * 1952-03-22 1957-02-19 Fkg Fritz Kesselring Geratebau Alternating current switching device
US2859400A (en) * 1952-03-22 1958-11-04 Fkg Fritz Kesselring Geratebau Alternating current switching device
US2791739A (en) * 1954-05-20 1957-05-07 Philips Corp Circuit arrangement for converting a lower d. c. voltage into a higher d. c. voltage
US2873419A (en) * 1955-09-22 1959-02-10 Bbc Brown Boveri & Cie Arc-back prevention circuit

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3165640A (en) * 1960-12-15 1965-01-12 North American Aviation Inc D. c. controlled semiconductor switch for a. c. current
US3699402A (en) * 1970-07-27 1972-10-17 Gen Electric Hybrid circuit power module
US4249223A (en) * 1978-12-01 1981-02-03 Westinghouse Electric Corp. High voltage DC contactor with solid state arc quenching
US4296449A (en) * 1979-08-27 1981-10-20 General Electric Company Relay switching apparatus
US4276484A (en) * 1979-09-10 1981-06-30 Riveros Carlos A Method and apparatus for controlling current in inductive loads such as large diameter coils
USRE33314E (en) * 1984-10-10 1990-08-28 Mars Incorporated Vending machine power switching apparatus
US5536980A (en) * 1992-11-19 1996-07-16 Texas Instruments Incorporated High voltage, high current switching apparatus
US8619395B2 (en) 2010-03-12 2013-12-31 Arc Suppression Technologies, Llc Two terminal arc suppressor
US9087653B2 (en) 2010-03-12 2015-07-21 Arc Suppression Technologies, Llc Two terminal arc suppressor
US9508501B2 (en) 2010-03-12 2016-11-29 Arc Suppression Technologies, Llc Two terminal arc suppressor
US10134536B2 (en) 2010-03-12 2018-11-20 Arc Suppression Technologies, Llc Two terminal arc suppressor
US10748719B2 (en) 2010-03-12 2020-08-18 Arc Suppression Technologies, Llc Two terminal arc suppressor
US11295906B2 (en) 2010-03-12 2022-04-05 Arc Suppression Technologies, Llc Two terminal arc suppressor
US11676777B2 (en) 2010-03-12 2023-06-13 Arc Suppression Technologies, Llc Two terminal arc suppressor
WO2013131557A1 (en) * 2012-03-06 2013-09-12 Abb Technology Ag Arc-jump circuit breaker and method of circuit breaking

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Publication number Publication date
GB849240A (en) 1960-09-21
DE1160059B (de) 1963-12-27
FR1193942A (da) 1959-11-05

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