US3863041A - High-voltage circuit-interrupter having a closing resistance and improved shunting-resistance contacts therefor - Google Patents

High-voltage circuit-interrupter having a closing resistance and improved shunting-resistance contacts therefor Download PDF

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Publication number
US3863041A
US3863041A US421574A US42157473A US3863041A US 3863041 A US3863041 A US 3863041A US 421574 A US421574 A US 421574A US 42157473 A US42157473 A US 42157473A US 3863041 A US3863041 A US 3863041A
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United States
Prior art keywords
resistance
contacts
closing
movable
main
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Expired - Lifetime
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US421574A
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English (en)
Inventor
Joseph R Rostron
Sylvester J Dropik
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ABB Inc USA
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Westinghouse Electric Corp
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Application filed by Westinghouse Electric Corp filed Critical Westinghouse Electric Corp
Priority to US421574A priority Critical patent/US3863041A/en
Priority to CA213,969A priority patent/CA977397A/en
Priority to JP1974145845U priority patent/JPS5649084Y2/ja
Application granted granted Critical
Publication of US3863041A publication Critical patent/US3863041A/en
Assigned to ABB POWER T&D COMPANY, INC., A DE CORP. reassignment ABB POWER T&D COMPANY, INC., A DE CORP. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: WESTINGHOUSE ELECTRIC CORPORATION, A CORP. OF PA.
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Expired - Lifetime legal-status Critical Current

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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
    • H01H33/04—Means for extinguishing or preventing arc between current-carrying parts
    • H01H33/16—Impedances connected with contacts
    • H01H33/166—Impedances connected with contacts the impedance being inserted only while closing the switch

Definitions

  • ABSTRACT An improved high-voltage circuit-interrupter is pro vided having series main contacts and resistance contacts with a closing resistance shunting the resistance contacts, so that the closing resistance is inserted into the circuit during the closing operation of the high-voltage circuit-interrupter, but is out of the circuit during the opening operation.
  • An improved mechanism is provided for utilizing the inertia of the movable resistance contact-frame and a relatively light biasing means, such as a light compression spring.
  • the construction is such that the main driving frame, carrying the movable main contact or contacts, carries therealong also the movable resistance contact-frame, with the contact overlap distance being such that the main contacts are closed prior to the closing of the serially-related resistance contacts, thereby inserting the closing resistance into the circuit momentarily during the closing operation of the high-voltage circuit-interrupter.
  • 3,291,947 there is illustrated a rotating bridging type of separable main contact structure with an auxiliary resistance contact associated with each stationary contact, so arranged that the closing resistance, of a desirable specified ohmic value, is inserted into the controlled circuit at a predetermined time diring the closing operation, and is ultimately shorted out in the fully closed-circuit position of the interrupter.
  • the arrangement is such that the closing resistance is out of the circuit during the opening operation, and the extinguishing action, or arc interruption, occurs only at the separable rotating main contact structure and not at the closing-resistance contacts, which obviously is desirable.
  • serially related separable main contacts and separable resistance contacts with a closing resistance in shunt with the separable resistance contacts.
  • the mechanical operating control for the opening of the main contacts, and the opening of the resistance contacts is such that the main frame, carrying the movable main contact structure, is in abutment with the frame for the movable resistance contacts during the closing operation, and the contact overlap distance, relative to the main contacts and resistance contacts, is such that the main contacts close prior to the subsequent closing of the resistance contacts, so that, in effect, the closing resistance is inserted into the circuit momentarily during the closing operation of the interrupter.
  • the two equipment frames are again in abutment and in readiness for a subsequent closing operation of the interrupter.
  • the inertia of the resistance-frame for the movable resistance contact insures that the separable resistance contacts will remain closed, thereby shorting the closing resistance out of the circuit during such an opening operation, and also insuring that the arc-extinguishing action occurs only at the main separable contacts adaptable for this purpose, and not at the separable resistance contacts.
  • FIG. 1 is an end elevational view of a three-phase circuit-interrupter of the gas-blast type embodying the principles of the present invention
  • FIG. 2 is a side-elevational view of the three-phase gas-blast circuit-interrupter of FIG. 1;
  • FIG. 3 is a top plan view of the three-phase gas-blast circuitinterrupter of FIGS. 1 and 2;
  • FIG. 4 is a somewhat diagrammatic view of the operating linkage and ground-potential mechanism for actuating the valve-tripping rods for pneumatically actuating the three pole-units of the three-phase gas-blast circuit-interrupter of FIG. 1, the valve-linkage being illustrated in the closed-circuit position of the circuitinterrupter;
  • FIG. 5A is an enlarged side-elevational view, partially in vertical section, of the upper main arc-extinguishing unit of one-half of a pole-unit of the breaker, the contact structure being illustrated in the closed-circuit position;
  • FIG. 5B shows the lower portion of the breaker of FIG. 5A, again the contacts being shown closed;
  • FIG. 6A is a vertical sectional view of the upper main contact structure for the upper main arc-extinguishing unit, the illustration showing the separable main contacts in the fully open-circuit position;
  • FIG. 6B is a fragmentary enlarged view of the lowermost main contact structure showing the latter in the fully open-circuit position. It will be noted that this extinguishing structure is in series with the upper main contact structure shown in FIG. 6A;
  • FIG. 6C is an enlarged vertical sectional view showing the separable resistance contacts with these contacts in the fully open-circuit position of the interrupter
  • FIG. 7B is a generally vertical sectional view taken through the second main contact structure of the arcextinguishing unit disposed immediately below the upper arc-extinguishing unit, illustrated in FIG. 7A,
  • FIG. 7C is an enlarged vertical sectional view taken through the lower separable resistance contacts, the resistance contacts being illustrated in the closed-circuit position;
  • FIG. 8 is a diagrammatic view of the circuit illustrating the location and arrangement of the two main arcextinguishing units for each'side of the pole-unit, with an indication of the location of the closing-resistance contacts, and the relationship of the closing resistance relative to the separable resistance contacts, all of the contacts being illustrated in the closed-circuit position of the circuit-interrupter;
  • FIG. 11 is a sectional view taken substantially along the line XI-XI of FIG. 5A;
  • FIG. 12 is a top plan view of the closing-resistance assemblage of FIG. 13;
  • FIG. 13 is a generally side elevational view of the closingresistance assemblage.
  • FIGS. 1-4 of the drawings there is illustrated a three-phase high-voltage circuitinterrupter of the gas-blast type 1, such as set forth in US. Pat. No. 3,596,028, many detailed component parts of which are described in said patent, and also in the patents referred to in said U.S. Pat. No. 3,596,028.
  • Various details of the operating structure may be gleaned from a reading of the aforesaid US. Pat. No. and the patents therein referred to.
  • each column structure 3, 4 contains two main arc-extinguishing units 6 and 7 together with a lower resistance unit 9, which has the resistance contacts 11, 12 thereof controlled in such a manner that during the closing operation of the interrupter l, the closing resistance 14 is inserted serially into the circuit to damp any high voltage surges occurring on the line 16 (FIG. 1).
  • the closing resistance 14 is inserted serially into the circuit to damp any high voltage surges occurring on the line 16 (FIG. 1).
  • the function of the separable closing contacts I1, 12 is to achieve this end.
  • FIG. 1 of the drawings there are provided two identical interrupting assemblages 3 and 4 slantingly arranged away from each other, as illustrated in FIG. 1, and each of which contains two serially related main contact assemblages 21, 22, together with a serially related separable resistance contact assemblage 13, which controls the insertion of the closing resistance 14.
  • the upper frame-assembly 28 includes a generally I-I-shaped structure including transverse bridging members 39, 40, together with a pair of downwardly extending interconnecting movable operating rods 30, 31.
  • the lower ends of the operating rods 30, 31 are hollow, as indicated at 42 in FIG. 7C, and make separable abutment connection at 44 with a resilient bumper 46, such as of rubber, affixed to and secured to an upper crossmember 48 attached to the lower frame-assembly 33 associated with the movable resistance contact 11, as illustrated in FIGS. 6C, 7C and 9 of the drawings.
  • the shunting of the closing resistance 14 is, of course, desirable as well appreciated by those skilled in the art, inasmuch as it would lead to heating and energy losses in the closed-circuit position of the interrupter 1. Its use during the closing operation is to avoid the occurrence of high-voltage surges occurring on the line 16 during a closing operation.
  • the theory and functioning of a closing resistance of the proper value is, of course, set forth in the aforesaid Van Sickle U.S. Pat. No. 3,291,947, to which reference has been made and the subject matter of which is incorporated herein by reference.
  • the erosion and burning associated with the extinguishing of the arcs 18, 19 to occur only at the main two contact assemblages 21, 22 in the upper portion of the columnar arc-extinguishing assemblage 3.
  • the arrangement is such that the inertia of the lower resistance frame-assembly 33 is such that it hangs behind, or there is a lost-motion connection 32 between the two frame-assemblages 28 and 33 due to the inertia of the lower resistance frame-assemblage 33 and the relatively light biasing spring 50 of FIG. 7C.
  • the closing resistance assemblage 14 is more clearly set forth in FIGS. 12 and 13, where it will be observed that the carbon arcuate segments 54 are in compression, as caused by the compression springs 56, and connections 58 between the carbon resistance segments cause the resistance assemblage 14 to be of the right ohmic value, as set forth in the aforesaid Van Sickle U.S. Pat..No. 3,291,947.
  • each pole-unit A, B, or C there is provided the two closing resistances 14 together with their associated separable resistance contact assemblages 13, which function, during the opening operation, to keep the resistances 14 out of the circuit 16 during the interruption process.
  • the main contact structures 21, 22 are closed, whereas the separable resistance contacts 11, 12 are still open, so that the two resistances 14 are serially inserted into the circuit 16 during the closing operation to prevent high-voltage surges occurring on the line 16.
  • a main operating mechanism 64 at ground potential which is described in U.S. Pat. No. 3,642,329, which issued November 30, 1971 to Fischer et a1, effects rightward movement of an operating lever 66, which, through a connecting rod 68, effects counterclockwise rotation of two bell-crank levers 70, 71, each of which has an upstanding movable valve-rod 73 (FIG. 10) pivotally connected thereto at 75.
  • the two bell-crank levers 70, 71 are pivotally mounted on stationary pivots 77, 78.
  • the central bellcrank lever 70 is pivotally connected, by a connecting rod 80, to the left-hand bell-crank lever 82, which moves in a clockwise direction about a stationary pivot 84. Pivotally connected at 86 to the left-hand bellcrank lever 82 is the upstanding valve-rod 73 associated with the pole unit A.
  • An accelerating spring 90 shown in FIG. 4, bears 1 against a cap portion 92 affixed to the left-hand extremity of a guide-rod 94, the right-hand end of the lat ter being pivotally connected to the left-hand bellcrank lever 82. Accordingly, clockwise pivotal rotation of the driving lever 66 effects upward movement of all three valve-rods 73, which serve to pneumatically cause pressure to occur on the bottom side of an operating piston (not shown) constituting a part of the operator 26 illustrated in FIG. 5A of the drawings.
  • the operator 26 is set forth and described in U.S. Pat. No. 3,590,189, and during the closing operation, as described hereinbefore, causes downward movement of the I-I-shaped frame 28 comprising the two operating rods 30, 31 movable within stationary guide sleeves, or tubes 96, 97, and serving to simultaneously cause the downward closing movement of the two main movable contacts 20, 23.
  • a latching arrangement 100 (FIG. 7A) is associated with each main movable contact or 23, as disclosed more clearly in FIG. 6B of the drawings. It will be observed that there are provided a pair of pivotally mounted latches 102 biased radially inwardly by a pair of compression springs 104, only one latch assembly 102 being viewed in FIG. 6B of the drawings.
  • the construction is such that during the closed position, as viewed in FIG. 7A, the latches seat upon shoulder portions 106 associated with the secondary blast-valves 107, which, when open, permits gas flow to occur out ports 108 associated with the rear side of the upper movable main contact 20, as viewed in FIG. 6A. This gas-flow action is described in more detailin U.S. Pat. No. 3,596,028 to which reference may be made, and the subject matter of which is incorporated herein be reference.
  • FIGS. 6B and 7B show more clearly the mechanical interconnection of the movable main contact 23 of the lowermost main arc-extinguishing structure 7. It will be observed that a cross-member is mechanically interconnected between the two operating rods 30, 31, and
  • FIG. 7C serves somewhat the same function as the upper traverse member 39 of FIGS. 6A and 7A.
  • the two main operating rods 30, 31 have lower hollow extensions 42 which encompass projections 35 affixed to the lower traverse frame-member 48 of the resistance assemblage 33, as indicated more clearly in FIGS. 7C and 9 of the drawings.
  • the lostmotion between the lower hollow tubular extensions 30a, 31a of the two main operating rods 30, 31 and the resilient rubber bumpers 46, affixed to the resistance traverse member, is designated by the reference numeral 32 in FIG. 9, and the distance at this particular point of time is designated by the distance length D in FIG. 9 of the drawings. Consequently, FIG.
  • each columnar assemblage 3, 4 is an outer cylindrical insulating casing member 10, which holds the high-pressure gas 8 within the regions 99 externally of the two main contact structures 21, 22.
  • an outer porcelain casing 15 utilized for its weatherproof characteristics. Suitable means, not shown particularly, and not pertinent to the present invention, are provided for applyingcompressive force on the outer porcelain casing member 15 and corresponding tensile stress upon the inner insulating tubular casing 10.
  • the upper line connection L. is secured to a terminal structure 34 more clearly shown in FIG. 5A, which electrically connects the circuit 16 to the upper main movable contact 20.
  • the circuit 16 extends through both columnar assemblages 3. 4 and terminates at the upper end 34 of the other assemblage 4 of FIG. 1.
  • the inertia of the lower frame 33 comprising the traverse member 48, the movable resistance contact rod 87 and lower cup-shaped resistance contact member 11 is such that there occurs a lost-motion connection 32 (FIG. 9) with the upper rapidly moving main frame-structure 28 connecting the two main movable contacts 20, 23 mechanically together, and moving upwardly at very high speed during the opening operation of the breaker 1.
  • the compression spring 50 of FIG. 9 is relatively light and thereby incapable of maintaining abutment at the connection 44, thus permitting the upper frame 28 to pull away from the lower frame 33 during the initial portion of the opening operation of the breaker.
  • Suitable mechanical support tubes 59, 61 are provided to fixedly maintain the stationary contact structures 25, 27 in the desired stationary location, and to provide mechanical integrity of the arc-extinguishing assemblage 3 as a whole.
  • This resistor contact is for use in a high voltage power circuit breaker rated at 362 kV.
  • the breaker is capable of 40 kA interrupting ability and carrying 3,000 Amps continuously.
  • the pre-insertion resistors are available from 175 ohms to 300 ohms each. There are two of these per phase. They are electrically and thermally capable of closing into a full fault four times each hour. The contact shorts out the resistor from 6 to 9 milliseconds after it has been inserted into the circuit.
  • the use of a closing resistor optimally sized for each system reduces the over-voltages caused by closing the circuit breaker into a transmission line with a trapped charge, and subsequently reduces the electrical stress imposed on the entire power system's equipment. This stress is reduced to a miximum of 2.0 times the normal line to ground voltage whereas this maximum is 3.0 times the normal line to ground voltage when no closing resistor is used.
  • c. means defining a separable pair of resistance contacts including a movable resistance contact disposed in electrical series relationship with said separable pair of main contacts so that in the closed-circuit position of the circuit-interrupter the line current passes serially through the two pairs of separable contacts;
  • d. means defining a closing resistance connected electrically in shunt with said separable pair of resistance contacts so that when said separable pair of resistance contacts are closed the closing resistance is shorted out of the controlled circuit;
  • g. means biasing said second member and said movable resistance contact to the open-circuit position
  • extinguishing gas comprises sulfur-hexafiuoride (SP gas.

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  • Arc-Extinguishing Devices That Are Switches (AREA)
  • Circuit Breakers (AREA)
US421574A 1973-12-04 1973-12-04 High-voltage circuit-interrupter having a closing resistance and improved shunting-resistance contacts therefor Expired - Lifetime US3863041A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US421574A US3863041A (en) 1973-12-04 1973-12-04 High-voltage circuit-interrupter having a closing resistance and improved shunting-resistance contacts therefor
CA213,969A CA977397A (en) 1973-12-04 1974-11-18 High-voltage circuit-interrupter having a closing resistance and improved shunting-resistance contacts therefor
JP1974145845U JPS5649084Y2 (enrdf_load_stackoverflow) 1973-12-04 1974-12-04

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US421574A US3863041A (en) 1973-12-04 1973-12-04 High-voltage circuit-interrupter having a closing resistance and improved shunting-resistance contacts therefor

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US3863041A true US3863041A (en) 1975-01-28

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JP (1) JPS5649084Y2 (enrdf_load_stackoverflow)
CA (1) CA977397A (enrdf_load_stackoverflow)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4005345A (en) * 1974-11-27 1977-01-25 Westinghouse Electric Corporation Multi-phase gas-type circuit-interrupter substitution modular construction
US4013853A (en) * 1974-11-27 1977-03-22 Westinghouse Electric Corporation Multi-phase compressed-gas circuit-breaker construction
US4024365A (en) * 1974-11-27 1977-05-17 Westinghouse Electric Corporation Compressed-gas multiphase circuit-breaker installation
US4069406A (en) * 1975-12-02 1978-01-17 Allis-Chalmers Corporation Closing resistor switch for gas insulated circuit breaker
US4338500A (en) * 1979-03-02 1982-07-06 Societe Anonyme Dite: Delle-Alsthom Device for switching in a resistance when a circuit breaker closes a circuit
US4617435A (en) * 1984-08-28 1986-10-14 Kabushiki Kaisha Toshiba Hybrid circuit breaker
US6483679B1 (en) 2001-06-18 2002-11-19 Southern States, Inc. Capacitor switch with external resistor and insertion whip
US20050128662A1 (en) * 2003-12-15 2005-06-16 Rostron Joseph R. Capacitor switch with internal retracting impedance contactor
US20140076853A1 (en) * 2012-09-14 2014-03-20 Abb Technology Ag Telescoping Current Path Structure For Dual Tank Dead Tank Circuit Breaker With Parallel Resistor Assembly

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1563833A (en) * 1919-12-05 1925-12-01 Electrical Engineer S Equipmen High-tension air-break switch
US3287531A (en) * 1963-12-30 1966-11-22 Mitsubishi Electric Corp Terminal bushing having impedance means associated therewith
US3291947A (en) * 1964-06-12 1966-12-13 Westinghouse Electric Corp Interrupting structures for compressedgas circuit interrupters having double-break hollow rotative moving contact-arm assembly
US3393285A (en) * 1965-12-30 1968-07-16 Allis Chalmers Mfg Co Contact arrangements in oil circuit interrupter
US3538276A (en) * 1967-11-24 1970-11-03 Westinghouse Electric Corp High-voltage circuit breaker having two-step closing resistance

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS437690Y1 (enrdf_load_stackoverflow) * 1965-06-04 1968-04-06

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1563833A (en) * 1919-12-05 1925-12-01 Electrical Engineer S Equipmen High-tension air-break switch
US3287531A (en) * 1963-12-30 1966-11-22 Mitsubishi Electric Corp Terminal bushing having impedance means associated therewith
US3291947A (en) * 1964-06-12 1966-12-13 Westinghouse Electric Corp Interrupting structures for compressedgas circuit interrupters having double-break hollow rotative moving contact-arm assembly
US3393285A (en) * 1965-12-30 1968-07-16 Allis Chalmers Mfg Co Contact arrangements in oil circuit interrupter
US3538276A (en) * 1967-11-24 1970-11-03 Westinghouse Electric Corp High-voltage circuit breaker having two-step closing resistance

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4005345A (en) * 1974-11-27 1977-01-25 Westinghouse Electric Corporation Multi-phase gas-type circuit-interrupter substitution modular construction
US4013853A (en) * 1974-11-27 1977-03-22 Westinghouse Electric Corporation Multi-phase compressed-gas circuit-breaker construction
US4024365A (en) * 1974-11-27 1977-05-17 Westinghouse Electric Corporation Compressed-gas multiphase circuit-breaker installation
US4069406A (en) * 1975-12-02 1978-01-17 Allis-Chalmers Corporation Closing resistor switch for gas insulated circuit breaker
US4338500A (en) * 1979-03-02 1982-07-06 Societe Anonyme Dite: Delle-Alsthom Device for switching in a resistance when a circuit breaker closes a circuit
US4617435A (en) * 1984-08-28 1986-10-14 Kabushiki Kaisha Toshiba Hybrid circuit breaker
US6483679B1 (en) 2001-06-18 2002-11-19 Southern States, Inc. Capacitor switch with external resistor and insertion whip
US6597549B2 (en) 2001-06-18 2003-07-22 Southern States Llc Capacitor switch with external resistor and insertion whip
US20050128662A1 (en) * 2003-12-15 2005-06-16 Rostron Joseph R. Capacitor switch with internal retracting impedance contactor
US7078643B2 (en) 2003-12-15 2006-07-18 Rostron Joseph R Capacitor switch with internal retracting impedance contactor
US20140076853A1 (en) * 2012-09-14 2014-03-20 Abb Technology Ag Telescoping Current Path Structure For Dual Tank Dead Tank Circuit Breaker With Parallel Resistor Assembly
US9105427B2 (en) * 2012-09-14 2015-08-11 Abb Technology Ag Telescoping current path structure for dual tank dead tank circuit breaker with parallel resistor assembly

Also Published As

Publication number Publication date
JPS5649084Y2 (enrdf_load_stackoverflow) 1981-11-16
JPS5082328U (enrdf_load_stackoverflow) 1975-07-15
CA977397A (en) 1975-11-04

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AS Assignment

Owner name: ABB POWER T&D COMPANY, INC., A DE CORP., PENNSYLV

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:WESTINGHOUSE ELECTRIC CORPORATION, A CORP. OF PA.;REEL/FRAME:005368/0692

Effective date: 19891229