US3148260A - Disconnecting switch having surge suppressing impedance - Google Patents

Disconnecting switch having surge suppressing impedance Download PDF

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Publication number
US3148260A
US3148260A US185575A US18557562A US3148260A US 3148260 A US3148260 A US 3148260A US 185575 A US185575 A US 185575A US 18557562 A US18557562 A US 18557562A US 3148260 A US3148260 A US 3148260A
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US
United States
Prior art keywords
blade
switch
main
circuit
resistor
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.)
Expired - Lifetime
Application number
US185575A
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English (en)
Inventor
Jr Chester W Upton
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.)
Westinghouse Electric Corp
Original Assignee
Westinghouse Electric Corp
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
Priority to BE630613D priority Critical patent/BE630613A/xx
Application filed by Westinghouse Electric Corp filed Critical Westinghouse Electric Corp
Priority to US185575A priority patent/US3148260A/en
Priority to GB7504/63A priority patent/GB974156A/en
Application granted granted Critical
Publication of US3148260A publication Critical patent/US3148260A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • 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
    • H01H33/12—Auxiliary contacts on to which the arc is transferred from the main contacts
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B17/00—Insulators or insulating bodies characterised by their form
    • H01B17/42—Means for obtaining improved distribution of voltage; Protection against arc discharges
    • H01B17/44—Structural association of insulators with corona rings
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H31/00—Air-break switches for high tension without arc-extinguishing or arc-preventing means
    • H01H31/02—Details
    • H01H31/026—Movable parts and contacts mounted thereon
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H31/00—Air-break switches for high tension without arc-extinguishing or arc-preventing means
    • H01H31/26—Air-break switches for high tension without arc-extinguishing or arc-preventing means with movable contact that remains electrically connected to one line in open position of switch
    • H01H31/28—Air-break switches for high tension without arc-extinguishing or arc-preventing means with movable contact that remains electrically connected to one line in open position of switch with angularly-movable contact
    • 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
    • H01H9/48—Means for preventing discharge to non-current-carrying parts, e.g. using corona ring
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H31/00—Air-break switches for high tension without arc-extinguishing or arc-preventing means
    • H01H31/26—Air-break switches for high tension without arc-extinguishing or arc-preventing means with movable contact that remains electrically connected to one line in open position of switch
    • H01H31/28—Air-break switches for high tension without arc-extinguishing or arc-preventing means with movable contact that remains electrically connected to one line in open position of switch with angularly-movable contact
    • H01H2031/286—Air-break switches for high tension without arc-extinguishing or arc-preventing means with movable contact that remains electrically connected to one line in open position of switch with angularly-movable contact wherein the contact is rotatable around its own longitudinal axis

Definitions

  • This invention relates, generally, switches and, more particularly, to a switch having a surge suppressing impedance or resistor inserted into circuit during the opening operation of the switch.
  • An object of this invention is to provide for inserting a surge suppressing impedance or resistor in the circuit through a disconnecting switch prior to the establishing of an arc during opening of the switch.
  • Another object of the invention is to provide an auxiliary blade which cooperates with the main blade of a disconnecting switch to insert a surge suppressing resistor in the circuit through the switch.
  • a further object of the invention is to provide a corona shield for a spring-biased auxiliary blade on a disconnecting switch.
  • Still another object of the invention is to provide for resetting the spring-biased auxiliary blade during closing of the main blade of the switch.
  • a spring-biased auxiliary or flipper blade is so incorporated in a switch and impedance assembly that a parallel circuit through the flipper blade and the first stage or section of the impedance assembly becomes a series circuit immediately upon breaking the circuit through the main contacts of the switch.
  • FIGURE 1 is a view, partly in side elevation and partly in section, of a portion of a disconnecting switch and surge suppressing resistor assembly embodying the principal features of the invention
  • FIGS. 2 and 3 are views, in section, taken along the lines II-II and III-III, respectively, in FIG. 1;
  • FIG. 4 is a view, in plan, looking along the line IV-IV in FIG. 1.
  • the impedance assembly is generally of the type described in Patent 3,004,117. As described in that patent, the impedance assembly functions as a surge suppressing resistor during opening of the disconnecting switch.
  • the portion of the disconnecting switch shown in the present drawing comprises a supporting insulator stack 10 upon which is mounted a combination break jaw support, surge suppressor support and terminal pad 11 composed of suitable conducting material, such as copper.
  • a terminal connector 12 is attached to what may be called a terminal pad 11 for connecting a power conductor (not shown) to the switch.
  • a stationary contact or break jaw 13 is attached to the terminal pad 11.
  • a main switch blade 14 engages the stationary contact 13 when the blade is in the closed position.
  • a generally hemispherically-shaped corona ball 15 is secured to the end of the blade 14.
  • the blade 14 is of the swinging type and the ball 15 follows an arcuate path 16 during opening and closing of the switch blade.
  • An actuating mechanism (not shown) which may be of any suitable type such as, for example, the one described in Patent 2,436,296, issued February 17, 1948, to H. W. Graybill and P. Olsson, may be utilized for operating the switch blade 14.
  • the blade operating mechanism may be supported by insulator supports similar to the insulator stack 10.
  • a power conductor may be connected to the blade operating mechanism thereby completing an electric circuit through the switch when the main blade 14 is closed.
  • the impedance assembly comprises three resistor sections 17 which are inserted in three successive stages A, B and C in series with the are drawn during opening of the switch.
  • Each resistor section 17 may comprise a hollow insulating cylinder 18 inside of which is disposed a suitable resistance element which may be of the carbon block type.
  • the cylinder 18 may be composed of porcelain or other suitable insulating material, such as an epoxy resin.
  • a supporting casting 19, having an external flange 20 thereon, may be cemented to each end of each cylinder 18.
  • the bottom casting 19 of the lowermost resistor section 17 may be attached to the terminal pad 11 by mounting bolts 21.
  • the mounting castings 19 on the adjacent ends of the resistor sections 17 may be joined together by similar mounting bolts 21 which extend through the flanges 20 on the mounting castings. If desired, a single wire-wound resistor with taps thereon may be utilized in place of separate sections of resistance.
  • a generally U-shaped corona shield 22 is attached to a mounting plate 23 which is disposed between the mounting castings 19 of the resistor sections 17 of the impedance stages A and B. As shown in FIGS. 1 and 2, the legs of the shield 22 are bent inwardly and upwardly.
  • the shield 22 is preferably formed from a hollow metal tube.
  • a generally ring or doughnut-shaped corona shield 24 is attached to a mounting plate 25.
  • the plate 2.5 is secured between the mounting castings 19 for the resistor sections 17 of impedance stages B and C.
  • a generally ovalshaped corona shield 26 is attached to a mounting plate 27.
  • the plate 27 is attached to the top casting 19 of the resistor section 17 of the impedance stage C.
  • the corona shields 24 and 26 are also formed from cylindrical metal tubing.
  • the rings 28 are preferably formed from cylindrical metal tubing.
  • the supporting plate 23 and the corona shields 24 and 26 are spaced from the arcuate path 16 traveled by the end 15 of the main blade 14.
  • these members function as arcing contacts during opening of the switch. The are transfers from one arcing contact to the next as the blade 14 swings open. In this manner, the resistance of the impedance assembly is inserted into the circuit by increments until the entire resistance is in the circuit;
  • a spring-biased flipper or auxiliary switch blade 31 is disposed to engage I the end 15 of the main switch blade 14 when the main blade engages the break jaws or stationary contact 13.
  • the auxiliary blade 31 is generally of a hair-pin shape with the ends of its legs formed into a torsion spring and attached to the mounting plate 23 to bias the blade 31 against the corona ball 15 on the main blade 14.
  • the first stage A of the impedance assembly is connected in parallel circuit relation with the circuit through the break jaw 13 when the main blade 14 is closed.
  • the parallel circuit extends through the auxiliary blade 31 and the lowermost resistor section 117 to the terminal pad 11 to which the break jaw 13 is also attached. It, however, carries negligible current in the closed position since it is a high resistance path relative to the main switch blade contacts.
  • the auxiliary blade 31 follows the main blade and remains in contact with the ball 15 until the auxiliary blade 31 engages the mounting plate 23 which functions as a stop member to stop the upward movement of the auxiliary blade 31, thereby separating the auxiliary blade from the main blade as the main blade continues to travel upwardly.
  • the circuit to the resistor sections 17 becomes a series circuit and the first increment of resistance is inserted in series with the arc to be initiated after the end 15 f the main blade 14 leaves the auxiliary blade 31.
  • the auxiliary blade 31 prevents arcing Therefore, the auxiliary blade 31 is encompassed by the shield 22 when the blade 31 is in the open position.
  • an arc is first drawn between the auxiliary blade 31 or the corona shield 22 which function as an arcing contact and the main switch blade corona ball as the main blade travels upwardly.
  • the first stage A of the impedance assembly is in series with the arc path.
  • the arc transfers to the corona shield 24 which functions as an arcing contact.
  • the resistance of the second stage B is added to the first stage A which are now connected in series in the arc circuit.
  • the arc transfers to the corona shield 26 thereby connecting the third stage C until after the main switch blade has completely cleared the break jaw and the corona shields 28.
  • the insertion of resistance into the circuit before any arcing takes place makes the surge suppressing resistor most effective in eliminating overvoltages or surges during the interruption of the circuit through the disconnecting switch.
  • the corona ball 15 retrieves the auxiliary blade 31 from within the first stage corona shield 22 and drives it downward against the torsion spring bias to the closed position shown in FIG. 1 of the drawing.
  • auxiliary blade which incorporates its own torsion spring must inherently be of small diameter material. It is, therefore, necessary for the auxiliary blade to be within the protective shield of the jaw corona shield 28 when the switch is closed. In the open position, the auxiliary blade comes to rest within the protective shield of the first stage corona shield and arcing contact. Therefore, it is shielded in both the open and the closed positions and is within the protective Zone of both shields during operation. It will be noted that the auxiliary bade 31 is bent in a manner similar to the manner in which the legs of the shield 22 are bent.
  • the particular numerical value of the resistance in ohms employed in the impedance assemblage depends upon the circuit components and the voltage. Its electrical dimensioning is described in detail and claimed in the aforesaid Patent 3,004,116. Generally, the resistance value is preferably several times the surge impedance of the circuit connected to the disconnecting switch. The current magnitude encountered in the application of switches of the present type is relatively low. Therefore, there isno burning or pitting of the auxiliary blade 31, corona ball 15 and the corona shields 22, Z4, 26 which function as arcing contacts.
  • the present invention provides for inserting resistance into the circuit through a disconnecting switch before any arcing is initiated during opening of the switch. In this manner, the effectiveness of a surge suppressing resistor in eliminating overvoltages or surges on a power system during switching operations is increased. Any overvoltage associated with restriking of the arc drawn during opening of the switch is damped by the external resistance and the system is protected.
  • a disconnecting switch comprising a relatively stationary contact, a swinging main switch blade engageable with the stationary contact to complete an electrical circuit through the switch and movable to open the switch, a resistor having one terminal electrically connected to the stationary contact, a spring-biased auxiliary switch blade electrically connected to another terminal of the resistor, said auxiliary switch blade being disposed to engage the main switch blade to establish a circuit through the resistor in parallel with the circuit through the stationary contact when the main blade engages the stationary contact and to follow at least a portion of the movement of said main switch blade, said parallel circuit becoming a series circuit through the main blade, the auxiliary blade and the resistor as soon as the main blade is separated from the stationary contact during opening of the switch, and stop means for disengaging the auxiliary blade from the main blade after the main blade is completely separated from the stationary contact.
  • a disconnecting switch comprising a relatively stationary contact, a swinging main switch blade engageable with the stationary contact to complete an electrical circuit through the switch and movable to open the switch, a resistor having one terminal electrically connected to the stationary contact, an auxiliary switch blade electrically connected to another terminal of the resistor, spring means for biasing the auxiliary blade against the main blade to establish a circuit through the resistor when the main blade engages the stationary contact to cause said auxiliary blade to follow the main blade for at least a portion of the movement of said main blade, said circuit through the auxiliary blade and the resistor being maintained in series with said main blade immediately upon and during opening of the switch until after the main blade is completely separated from the stationary contact, and stop means for disengaging the auxiliary blade from the main blade when the main blade has traveled a pre determined distance from the stationary contact.
  • a disconnecting switch comprising a relatively stationary contact, a swinging main switch blade engageable with the stationary contact to complete an electrical circuit through the switch, a resistor having one terminal electrically connected to the stationary contact, an auxiliary switch blade electrically connected to another terminal of the resistor, spring means for biasing the auxiliary blade against the main blade to establish a circuit through the resistor when the main blade engages the stationary contact, said circuit through the auxiliary blade and the resistor being maintained during opening of the switch until after the main blade is completely separated from the stationary contact, stop means for disengaging the auxiliary blade from the main blade when the main blade has traveled a predetermined distance from the stationary contact, and a corona shield encompassing the auxiliary blade when it engages the stop means.
  • a disconnecting switch in combination, a relatively stationary contact, a main switch blade engageable with the stationary contact to complete an electrical circuit through the switch and movable to open the switch, said main blade being movable through an arcuate path of travel, an impedance assembly comprising a plurality of resistor sections disposed adjacent the stationary contact and extending therefrom in the general direction of said path of travel, a plurality of arcing contacts tapped into said impedance assembly to insert impedance into the circuit during opening of the switch, said arcing contacts being spaced from said arcuate path of travel, an auxiliary switch blade engaging the main blade to connect one resistor section in the circuit when the main blade is closed, spring means biasing the auxiliary blade against the main blade to follow the movement of said main blade during at least a portion of the movement of said main blade and to maintain the circuit through the auxiliary blade and the resistor in series with said main switch blade immediately upon and during the opening of said switch until after the main blade is separated from the stationary contact during opening of the switch and corona shielding
  • a disconnecting switch in combination, a relatively stationary contact, a main switch blade engageable with the stationary contact to complete an electrical circuit through the switch and movable to open the switch, said main blade being movable through an arcuate path of travel, an impedance assembly comprising a plurality of resistor sections disposed adjacent the stationary contact and extending therefrom in the general direction of said path of travel, a plurality of arcing contacts tapped into said impedance assembly to insert impedance into the circuit during opening of the switch, said arcing contacts being spaced from said arcuate path of travel, an auxiliary switch blade engaging the main blade to connect one resistor section in the circuit when the main blade is closed, spring means biasing the auxiliary blade against the main blade to cause said auxiliary blade to follow said main switch blade during at least a portion of the movement thereof to maintain the circuit through the auxiliary blade and the resistor in series with the main switch blade until after the main blade is separated from the stationary contact immediately upon and during opening of the switch, and stop means for disengaging the auxiliary blade
  • a disconnecting switch in combination, a relatively stationary contact, a main switch blade engageable with the stationary contact to complete an electrical circuit through the switch, said main blade being movable through an arcuate path of travel, an impedance assembly comprising a plurality of resistor sections disposed adjacent the stationary contact and extending therefrom in the general direction of said path of travel, a plurality of arcing contacts tapped into said impedance assembly to insert impedance into the circuit during opening of the switch, said arcing contacts being spaced from said arcuate path of travel, an auxiliary switch blade engaging the main blade to connect one resistor section in the circuit when the main blade is closed, spring means biasing the auxiliary blade against the main blade to maintain the circuit through the auxiliary blade and the resistor until after the main blade is separated from the stationary contact during opening of the switch, stop means for disengaging the auxiliary blade from the main blade when the main blade has traveled a predetermined distance along said arcuate path, and corona shielding means encompassing the auxiliary blade when it engages the

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Arc-Extinguishing Devices That Are Switches (AREA)
US185575A 1962-04-06 1962-04-06 Disconnecting switch having surge suppressing impedance Expired - Lifetime US3148260A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
BE630613D BE630613A (en(2012)) 1962-04-06
US185575A US3148260A (en) 1962-04-06 1962-04-06 Disconnecting switch having surge suppressing impedance
GB7504/63A GB974156A (en) 1962-04-06 1963-02-25 Electric disconnecting switch

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US185575A US3148260A (en) 1962-04-06 1962-04-06 Disconnecting switch having surge suppressing impedance

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US3148260A true US3148260A (en) 1964-09-08

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BE (1) BE630613A (en(2012))
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4695918A (en) * 1986-07-24 1987-09-22 S&C Electric Company Pre-insertion inductor arrangement
FR2674985A1 (fr) * 1991-04-08 1992-10-09 Gec Alsthom Engergie Inc Sectionneur a ouverture brusque.
US6483679B1 (en) 2001-06-18 2002-11-19 Southern States, Inc. Capacitor switch with external resistor and insertion whip
EP2341515A1 (en) * 2009-12-30 2011-07-06 ABB Technology A block of bushings of a three-phase rotary switch-disconnector
CN106024494A (zh) * 2016-07-27 2016-10-12 山东泰开隔离开关有限公司 一种1100kv开合超b类感应电流的户外高压交流接地开关
WO2019186308A1 (en) * 2018-03-28 2019-10-03 Abb Schweiz Ag Spring loaded auxiliary contact system for bus transfer switching in a center break switch

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
US1861129A (en) * 1929-08-26 1932-05-31 Milliken Humphreys Circuit breaker
US2571864A (en) * 1947-08-21 1951-10-16 Westinghouse Electric Corp Arc extinguishing circuit interrupter
US2840671A (en) * 1954-08-30 1958-06-24 Siemens Ag Circuit interrupter
US3004117A (en) * 1958-04-30 1961-10-10 Westinghouse Electric Corp Air-break disconnecting switches

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
US1861129A (en) * 1929-08-26 1932-05-31 Milliken Humphreys Circuit breaker
US2571864A (en) * 1947-08-21 1951-10-16 Westinghouse Electric Corp Arc extinguishing circuit interrupter
US2840671A (en) * 1954-08-30 1958-06-24 Siemens Ag Circuit interrupter
US3004117A (en) * 1958-04-30 1961-10-10 Westinghouse Electric Corp Air-break disconnecting switches

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4695918A (en) * 1986-07-24 1987-09-22 S&C Electric Company Pre-insertion inductor arrangement
FR2674985A1 (fr) * 1991-04-08 1992-10-09 Gec Alsthom Engergie Inc Sectionneur a ouverture brusque.
US5228559A (en) * 1991-04-08 1993-07-20 Gec Alsthom Energie Inc. Section switch that opens suddenly
EP0591591A1 (fr) * 1991-04-08 1994-04-13 Gec Alsthom Energie Inc. Sectionneur à ouverture brusque
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
EP2341515A1 (en) * 2009-12-30 2011-07-06 ABB Technology A block of bushings of a three-phase rotary switch-disconnector
WO2011079926A3 (en) * 2009-12-30 2011-09-09 Abb Technology Ag A block of bushings of a three-phase rotary switch-disconnector
CN102667999A (zh) * 2009-12-30 2012-09-12 Abb技术有限公司 三相旋转开关断路器的套管组件
CN102667999B (zh) * 2009-12-30 2014-12-24 Abb技术有限公司 三相旋转开关断路器的套管组件
CN106024494A (zh) * 2016-07-27 2016-10-12 山东泰开隔离开关有限公司 一种1100kv开合超b类感应电流的户外高压交流接地开关
CN106024494B (zh) * 2016-07-27 2017-11-07 山东泰开隔离开关有限公司 一种1100kv开合超b类感应电流的户外高压交流接地开关
WO2019186308A1 (en) * 2018-03-28 2019-10-03 Abb Schweiz Ag Spring loaded auxiliary contact system for bus transfer switching in a center break switch
US11264183B2 (en) 2018-03-28 2022-03-01 Hitachi Energy Switzerland Ag Spring loaded auxiliary contact system for bus transfer switching in a center break switch

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GB974156A (en) 1964-11-04
BE630613A (en(2012))

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