US3652778A - Insulating spacer - Google Patents

Insulating spacer Download PDF

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Publication number
US3652778A
US3652778A US78373A US3652778DA US3652778A US 3652778 A US3652778 A US 3652778A US 78373 A US78373 A US 78373A US 3652778D A US3652778D A US 3652778DA US 3652778 A US3652778 A US 3652778A
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US
United States
Prior art keywords
central conductor
insulating member
shield
thermosetting resin
insulating
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
US78373A
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English (en)
Inventor
Yoshikazu Sakai
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.)
NGK Insulators Ltd
Original Assignee
NGK Insulators Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NGK Insulators Ltd filed Critical NGK Insulators Ltd
Application granted granted Critical
Publication of US3652778A publication Critical patent/US3652778A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
    • H02G5/00—Installations of bus-bars
    • H02G5/06—Totally-enclosed installations, e.g. in metal casings
    • H02G5/066—Devices for maintaining distance between conductor and enclosure
    • H02G5/068—Devices for maintaining distance between conductor and enclosure being part of the junction between two enclosures
    • 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
    • H01B17/26—Lead-in insulators; Lead-through insulators
    • H01B17/28—Capacitor type

Definitions

  • ABSTRACT PP 78373 An insulating spacer comprising a central conductor, a cylindrically shaped metallic shield which is arranged around said [30] Foreign Applicatlon Priority Data central conductor and is partially in contact with said central I conductor, an insulating member made of a thermosetting Oct. 16, 1969 Japan ..44/98379 resin Said shield is embedded into the inner diameter thereof and said central conductor is enclosed thereby, and a shield of [52] US. Cl. ..174/28, 174/16 B, 174/36, the earth side which is deeply embedded into a outwardly 174/99 B tending flange portion of said insulating member, and also [51] Int, Cl. ..H0lb 9/04 preferably comprises fib i f d resin f d f fib [58] Field olSearch ..174/28,29, 16 5,99 8,21,
  • the present invention relates to an insulating spacer, and more particularly to an insulating spacer which is to be employed for a duct line air power transmission bus bar, a gasfilled breaker or the like in which a sulfur hexafluoride gas is mainly used as an insulating medium.
  • a type of insulating spacer having an insulating member formed of a thermosetting resin such as epoxy resin in the prior arts has been customarily constructed in the manner that metallic flanges are fixed to the periphery of the insulating member for said insulating member to be secured to an external duct and a central contuctor is fixedly connected to the center of the insulating member for said central conductor to penetrate through the insulating member.
  • the construction as described above tends to cause gap spaces at the boundary portions between themetallic flange and the insulating member and as well between the central conductor and the insulating member in manufacturing steps, and moreover in operation of the insulating spacer said gap spaces being caused and spread by respective differences of the thermal expansion coeficients thereof while the expansion and contraction due to the variable heat exerted. Accordingly, it is impossible to obtain any satisfactory gas-tightness and as well to prevent corona discharge from being generated even under low voltage.
  • an insulating spacer according to this invention comprises a central conductor, a cylindrically shaped metallic shield arranged around said central conductor and partially in contact with said central conductor, an insulating member consisting of a thermosetting resin with said cylindrically shaped metallic shield being embedded into the inner wall thereof as to enclose said central conductor therewithin,
  • I and a shield of the earth side which is deeply embedded into a flange portion of said insulating member and also preferably comprises fiber-reinforced resin formed of fibrous tissues which is tightly wound arround a plurality of. independent grooves provided on the periphery of said central conductor and a thermosetting resin which is infiltrated into said fibrous tissues so that said insulating member formed of a thermosetting resin may be firmly fixed around over said central conductor, thus said insulating spacer being adapted to be applied to a duct line air powertransmission bus bar, gas-filled breaker or the like in which a sulfur hexafluoride gas is employed as an insulating medium.
  • the insulating spacer of the present invention comprises a central conductor and an insulating member provided around said central conductor, and as Well is characterized in that a cylindrically shaped metallic shield being arranged on the periphery of said central conductor and made partially in contact with said central conductor, said central conductor being enclosed by the insulating member formed of a thermosetting resin for said cylindrically shaped shield to be embedded into said insulating member, and a shield portion of an earth side shield being deeply embedded into an outwardly extending flange portion of said insulating member, and further preferably characterized in that said central conductor being provided with a plurality of annular grooves on the periphery thereof, and each of said grooves being filled with reinforced plastic layer formed of fibrous tissues which is tightly wound with tension around each of said grooves and a thermosetting resin which is infiltrated into said fibrous tissues.
  • the primary object of the present invention is to provide a much more highly efficient insulating spacer means which is adapted to be applied to a duct line air power transmission bus bar, gas-filled breaker or the like for extremely high voltage.
  • Another object of the present invention is to provide an insulating spacer improved in that the insulating member formed of a thermosetting resin is firmly fixed around over the central conductor for eliminating gap spaces which tends to cause undesirable condition, that is corona discharge or deterioration of insulation.
  • the reference numeral 1 designates a tubular or rod like central conductor, and the central conductor is arranged to be embedded as to penetrate through the center of an insulating member 2 formed of a thermosetting resin such as epoxy resin or the like and is also provided with annular projections 3,3 at the embedded portion therearound in'a suitably spaced relation.
  • a cylinder 4 made of a conductive material such as a metallic foil, a metal plate or ametallic meshes is closely arranged around the central conductor 1 between the annular projections 3,3 and is connected to the central conductor, thereby a shield 4 of the conductor side is provided as to be embedded into the inner wall of said insulating member 2.
  • the reference numeral 5 designates a shield of the earth side, which is embedded coaxially with the central conductor 1 into a flange portion 2 of the insulating member 2, and this earth side shield 5 consists of an annular shield portion 6 made of a conductive material such as a metallic foil, a metal plate or a metallic meshes as similar to that of the shield 4' and formed into the shape of a channel in cross section as shown in FIG. 1b, a plurality of conductive portions 7 provided on the annular shield portion 6, and cylindrical brackets 8 provided at the respective ends of the conductive portions 7.
  • Each of the brackets 8 is made to penetrate through the flange portion 2' of the insulating member 2 so that adjacent external ducts 10 may be fixedly joined at the projected flanges 10 thereof together with the insulating member 2 by means of bolts 9 inserted through the brackets 8.
  • the central conductor 1 is provided with a plurality of independent annular grooves 11 having the dimensions, for an example, of approximately 10 mm. in width, approximately 3 mm. in depth and approximately 10 mm. in pitch, and each of the grooves is filled with reinforced plastic layer 12 that is so called FRP formed of fibrous tissues such as roving, cloth or tape which is tightly wound with tension around said annular grooves 11 and a thermosetting resin such as epoxy resin or the like which is infiltrated into said fibrous tissues.
  • FRP reinforced plastic layer 12 that is so called FRP formed of fibrous tissues such as roving, cloth or tape which is tightly wound with tension around said annular grooves 11 and a thermosetting resin such as epoxy resin or the like which is infiltrated into said fibrous tissues.
  • the insulating member 2 formed of a thermosetting resin material such as epoxy resin or the like as above mentioned is put over around the central conductor after each of the annular grooves 11 have been previously filled with the reinforced plastic layer 12, since the reinforced plastic layer 12 is also formed of substantially the same thermosetting resin as the insulating member 2, the insulating member may be I V positively integrated together with the reinforced plastic layer.
  • the thermal expansion coefficient of the reinforced plastic layer 12 is provided with an intermediate value between that of the central conductor 1 made of a metal and that of the insulating member 2 made of a thermosetting resin, the reinforced plastic layer 12 serves as a buffer layer against the thermal shock caused between the central conductor l and the insulating member 2.
  • any occurrence of corona discharge due to foams involved in the reinforced plastic layer 12 may be prevented by means of the metallic shield 4, and in case of this shield being formed of a metallic meshes the insulating member 2 formed of a thermosetting resin can be rigidly fixed to the reinforced plastic layer 12 by impregnating said meshes with said resin without gap spaces.
  • each of the annular grooves l l filled with the reinforced plastic layer 12 is independently arranged, assuming that partial break away would be caused between the central conductor 1 and the reinforced plastic layer 12, this break away is effectively prevented from further spreading into the other portion of the layer.
  • FIG. 2 shows an another embodiment of the present invention which is different from FIG. 1a only in that annular projections as indicated 3,3 in FIG. la are omitted and an insulating member 2 is formed upright.
  • FIG. 3 shows an insulating spacer of the prior art in which gap spaces tends to be brought about at the adhesive boundary area 14 between the insulating member '2 and the metallic flange portion 13 arranged on the periphery of the insulating member 2 and at the boundary area 15 between the central conductor 1 and the insulating member 2.
  • the insulating spacer which is constituted as above mentioned according to this invention is practiced with sulfur hexafluoride gas being charged into each of closed chambers defined by the central conductors 1, external ducts 10 and the insulating spacers, since the shield portion 6 of the earth side shield 5 is deeply embedded into the flange portion 2' of the insulating member 2 formed of thermosetting resin such as epoxy resin or the like, any gap space is not brought about at the area of the earth side shield 5, and since the conductor side shield 4 is also firmly embedded into the insulating member 2 in connection with the central conductor 1, any gap space is not brought about as well at the area of the conductor side shield 4.
  • the insulating material is eroded by a resolved gases of the sulfur hexafluoride gas caused by the corona discharge, thus resulting in the insulation deterioration and damage of the insulating spacer being eliminated.
  • An insulating spacer comprising a central conductor and an insulating member provided around said central conductor, characterized in that said central conductor is provided with a plurality of grooves on the periphery thereof, each of said grooves is filled with reinforced plastic layer formed of fibrous tissues which is tightly wound with tension around each of said grooves and a thermosetting resin which is infiltrated into said fibrous tissues, a cylindrically shaped metallic shield is arranged on the periphery of said central conductor and made partially in contact with said central conductor, said central conductor is enclosed by the insulating member formed of a thermosetting resin for said cylindrically shaped shield to be embedded into said insulating member, and a shield portion of an earth side shield is deeply embedded into an outwardly extending flange portion of said insulating member.
  • thermosetting resin infiltrated into the reinforced plastic layers and the thermosetting resin formed into the insulating member are epoxy resin.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Installation Of Bus-Bars (AREA)
  • Insulating Bodies (AREA)
  • Gas-Insulated Switchgears (AREA)
US78373A 1969-10-16 1970-10-06 Insulating spacer Expired - Lifetime US3652778A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1969098379U JPS4791Y1 (enrdf_load_stackoverflow) 1969-10-16 1969-10-16

Publications (1)

Publication Number Publication Date
US3652778A true US3652778A (en) 1972-03-28

Family

ID=14218225

Family Applications (1)

Application Number Title Priority Date Filing Date
US78373A Expired - Lifetime US3652778A (en) 1969-10-16 1970-10-06 Insulating spacer

Country Status (2)

Country Link
US (1) US3652778A (enrdf_load_stackoverflow)
JP (1) JPS4791Y1 (enrdf_load_stackoverflow)

Cited By (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3829707A (en) * 1973-02-09 1974-08-13 Allis Chalmers Gas insulated high voltage electrical transmission line with means for damping transients
US3874237A (en) * 1973-02-15 1975-04-01 Canadian Patents Dev Liquid level height measuring apparatus
US3898368A (en) * 1973-09-24 1975-08-05 Siemens Ag Control electrode in a support insulator of an encapsulated gas-insulated tubular line
US3911198A (en) * 1974-01-08 1975-10-07 Siemens Ag Contact assembly for a metal-clad, gas-insulated high-voltage line
US3914530A (en) * 1973-09-18 1975-10-21 Siemens Ag Bearing for the support of the inner conductor of an encapsulated tubular line support in a support insulator
US3920885A (en) * 1975-03-14 1975-11-18 Gen Electric High-voltage, compressed-gas-insulated bus
US3962609A (en) * 1973-05-17 1976-06-08 Siemens Aktiengesellschaft Voltage transformer for a completely insulated high-voltage installation
US3990001A (en) * 1973-05-17 1976-11-02 Siemens Aktiengesellschaft Measuring transformer for installation in the metal enclosure of a switching installation
US4024339A (en) * 1975-06-19 1977-05-17 Westinghouse Electric Corporation Supporting insulator assembly for gas-insulated equipment
US4038486A (en) * 1975-06-10 1977-07-26 Westinghouse Electric Corporation Supporting insulator assembly for gas-insulated equipment
US4277746A (en) * 1978-02-03 1981-07-07 Hitachi, Ltd. Gas-insulated electric apparatus and method of detecting partial discharge therein
US4316051A (en) * 1978-03-13 1982-02-16 Bbc Brown, Boveri & Company, Ltd. Partition insulator having a predetermined rupture behavior
US4354154A (en) * 1974-02-27 1982-10-12 Siemens Aktiengesellschaft Measuring transformer for high-voltage switch-gear with metal encapsulation
US4562303A (en) * 1983-03-04 1985-12-31 Bbc Brown, Boveri & Company, Ltd. Disc-type insulator with a cast-in electrode and process for its manufacture
US5185497A (en) * 1990-10-30 1993-02-09 Siemens Aktiengesellschaft Single-pole gas-insulated line duct
US5571989A (en) * 1993-12-21 1996-11-05 Gec Alsthom T & D Sa Gas-insulated high-tension line for long distances
US5571990A (en) * 1993-12-21 1996-11-05 Gec Alsthom T & D Sa Gas-insulated single-phase cable for transporting electricity
US5608187A (en) * 1993-12-23 1997-03-04 Abb Research Ltd. Post insulator
EP0771999A3 (de) * 1995-11-02 1998-04-29 Briloner Leuchten GmbH Niedervoltstromschienensystem für Leuchten
US6268562B1 (en) * 1993-03-16 2001-07-31 Hitachi, Ltd. Sealed container and method for assembling it
US20020050746A1 (en) * 2000-10-26 2002-05-02 Mitsubishi Denki Kabushiki Kaisha Electromagnetic device
US6700234B2 (en) * 2000-10-26 2004-03-02 Mitsubishi Denki Kabushiki Kaisha Electromagnetic device
RU2295791C1 (ru) * 2005-06-14 2007-03-20 Институт систем обработки изображений Российской академии наук (ИСОИ РАН) Кабель для электропитания генераторов низкотемпературной плазмы
US20120103645A1 (en) * 2009-07-17 2012-05-03 Mitsubishi Electric Corporation Gas-insulated bus
US20120118600A1 (en) * 2009-07-10 2012-05-17 Ls Cable Ltd. Termination structure for superconducting cable
US20130025933A1 (en) * 2010-03-19 2013-01-31 Hitachi, Ltd. Insulating Spacer with Built-In Optical Fiber
CN103515898A (zh) * 2012-06-21 2014-01-15 西门子公司 一种盘形绝缘子
CN103563198A (zh) * 2011-06-08 2014-02-05 Abb研究有限公司 激光处理的导电衬底及其预先处理方法
US20160006224A1 (en) * 2013-03-15 2016-01-07 Siemens Aktiengesellschaft Dismantlable insulator for gas insulated switchgear
US20220021193A1 (en) * 2019-04-25 2022-01-20 Mitsubishi Electric Corporation Gas insulated bus

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3155787A (en) * 1961-05-30 1964-11-03 Moser Glaser Transformatoren A High voltage switch arrangement for insulated conductors
US3324272A (en) * 1965-07-26 1967-06-06 Westinghouse Electric Corp Termination of insulators
US3356785A (en) * 1963-11-19 1967-12-05 Sumitomo Electric Industries Electric transmission coaxial cables
US3391243A (en) * 1965-07-26 1968-07-02 Westinghouse Electric Corp Enclosed electric power transmission conductor
GB1133270A (en) * 1966-09-02 1968-11-13 Central Electr Generat Board Improvements in or relating to electric cables
CH476379A (de) * 1968-11-15 1969-07-31 Sprecher & Schuh Ag Metallgekapselte gasisolierte Hochspannungsleitung

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3155787A (en) * 1961-05-30 1964-11-03 Moser Glaser Transformatoren A High voltage switch arrangement for insulated conductors
US3356785A (en) * 1963-11-19 1967-12-05 Sumitomo Electric Industries Electric transmission coaxial cables
US3324272A (en) * 1965-07-26 1967-06-06 Westinghouse Electric Corp Termination of insulators
US3391243A (en) * 1965-07-26 1968-07-02 Westinghouse Electric Corp Enclosed electric power transmission conductor
GB1133270A (en) * 1966-09-02 1968-11-13 Central Electr Generat Board Improvements in or relating to electric cables
CH476379A (de) * 1968-11-15 1969-07-31 Sprecher & Schuh Ag Metallgekapselte gasisolierte Hochspannungsleitung

Cited By (38)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3829707A (en) * 1973-02-09 1974-08-13 Allis Chalmers Gas insulated high voltage electrical transmission line with means for damping transients
US3874237A (en) * 1973-02-15 1975-04-01 Canadian Patents Dev Liquid level height measuring apparatus
US3990001A (en) * 1973-05-17 1976-11-02 Siemens Aktiengesellschaft Measuring transformer for installation in the metal enclosure of a switching installation
US3962609A (en) * 1973-05-17 1976-06-08 Siemens Aktiengesellschaft Voltage transformer for a completely insulated high-voltage installation
US3914530A (en) * 1973-09-18 1975-10-21 Siemens Ag Bearing for the support of the inner conductor of an encapsulated tubular line support in a support insulator
US3898368A (en) * 1973-09-24 1975-08-05 Siemens Ag Control electrode in a support insulator of an encapsulated gas-insulated tubular line
US3911198A (en) * 1974-01-08 1975-10-07 Siemens Ag Contact assembly for a metal-clad, gas-insulated high-voltage line
US4354154A (en) * 1974-02-27 1982-10-12 Siemens Aktiengesellschaft Measuring transformer for high-voltage switch-gear with metal encapsulation
US3920885A (en) * 1975-03-14 1975-11-18 Gen Electric High-voltage, compressed-gas-insulated bus
US4038486A (en) * 1975-06-10 1977-07-26 Westinghouse Electric Corporation Supporting insulator assembly for gas-insulated equipment
US4024339A (en) * 1975-06-19 1977-05-17 Westinghouse Electric Corporation Supporting insulator assembly for gas-insulated equipment
US4277746A (en) * 1978-02-03 1981-07-07 Hitachi, Ltd. Gas-insulated electric apparatus and method of detecting partial discharge therein
US4316051A (en) * 1978-03-13 1982-02-16 Bbc Brown, Boveri & Company, Ltd. Partition insulator having a predetermined rupture behavior
US4562303A (en) * 1983-03-04 1985-12-31 Bbc Brown, Boveri & Company, Ltd. Disc-type insulator with a cast-in electrode and process for its manufacture
US5185497A (en) * 1990-10-30 1993-02-09 Siemens Aktiengesellschaft Single-pole gas-insulated line duct
US6268562B1 (en) * 1993-03-16 2001-07-31 Hitachi, Ltd. Sealed container and method for assembling it
US5571989A (en) * 1993-12-21 1996-11-05 Gec Alsthom T & D Sa Gas-insulated high-tension line for long distances
US5571990A (en) * 1993-12-21 1996-11-05 Gec Alsthom T & D Sa Gas-insulated single-phase cable for transporting electricity
US5608187A (en) * 1993-12-23 1997-03-04 Abb Research Ltd. Post insulator
EP0771999A3 (de) * 1995-11-02 1998-04-29 Briloner Leuchten GmbH Niedervoltstromschienensystem für Leuchten
US6700234B2 (en) * 2000-10-26 2004-03-02 Mitsubishi Denki Kabushiki Kaisha Electromagnetic device
US6960850B2 (en) 2000-10-26 2005-11-01 Mitsubishi Denki Kabushiki Kaisha Electromagnetic device in an automotive transmission with sulfur corrosion resistant insulating layer
US20020050746A1 (en) * 2000-10-26 2002-05-02 Mitsubishi Denki Kabushiki Kaisha Electromagnetic device
RU2295791C1 (ru) * 2005-06-14 2007-03-20 Институт систем обработки изображений Российской академии наук (ИСОИ РАН) Кабель для электропитания генераторов низкотемпературной плазмы
US20120118600A1 (en) * 2009-07-10 2012-05-17 Ls Cable Ltd. Termination structure for superconducting cable
US8912446B2 (en) * 2009-07-10 2014-12-16 Ls Cable Ltd. Termination structure for superconducting cable
US20120103645A1 (en) * 2009-07-17 2012-05-03 Mitsubishi Electric Corporation Gas-insulated bus
US8587930B2 (en) * 2009-07-17 2013-11-19 Mitsubishi Electric Corporation Gas-insulated bus
US20130025933A1 (en) * 2010-03-19 2013-01-31 Hitachi, Ltd. Insulating Spacer with Built-In Optical Fiber
US8847084B2 (en) * 2010-03-19 2014-09-30 Hitachi, Ltd. Insulating spacer with built-in optical fiber
CN103563198B (zh) * 2011-06-08 2017-05-24 Abb研究有限公司 激光处理的导电衬底及其预先处理方法
CN103563198A (zh) * 2011-06-08 2014-02-05 Abb研究有限公司 激光处理的导电衬底及其预先处理方法
CN103515898A (zh) * 2012-06-21 2014-01-15 西门子公司 一种盘形绝缘子
US9548600B2 (en) * 2012-06-21 2017-01-17 Siemen Aktiengesellschaft Disk-shaped insulator
US20150325993A1 (en) * 2012-06-21 2015-11-12 Siemens Aktiengesellschaft Disk-shaped insulator
US20160006224A1 (en) * 2013-03-15 2016-01-07 Siemens Aktiengesellschaft Dismantlable insulator for gas insulated switchgear
US20220021193A1 (en) * 2019-04-25 2022-01-20 Mitsubishi Electric Corporation Gas insulated bus
US12113345B2 (en) * 2019-04-25 2024-10-08 Mitsubishi Electric Corporation Gas insulated bus

Also Published As

Publication number Publication date
JPS4791Y1 (enrdf_load_stackoverflow) 1972-01-06

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