EP0012560A1 - Equipement électrique utilisant des isolants - Google Patents

Equipement électrique utilisant des isolants Download PDF

Info

Publication number
EP0012560A1
EP0012560A1 EP79302793A EP79302793A EP0012560A1 EP 0012560 A1 EP0012560 A1 EP 0012560A1 EP 79302793 A EP79302793 A EP 79302793A EP 79302793 A EP79302793 A EP 79302793A EP 0012560 A1 EP0012560 A1 EP 0012560A1
Authority
EP
European Patent Office
Prior art keywords
insulant
electrical equipment
fluid
maintaining
cable
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.)
Withdrawn
Application number
EP79302793A
Other languages
German (de)
English (en)
Inventor
Edward Arthur Burton
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.)
Dielectrics International Ltd
Original Assignee
Dielectrics International 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 Dielectrics International Ltd filed Critical Dielectrics International Ltd
Publication of EP0012560A1 publication Critical patent/EP0012560A1/fr
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B9/00—Power cables
    • H01B9/06—Gas-pressure cables; Oil-pressure cables; Cables for use in conduits under fluid pressure
    • H01B9/0611—Oil-pressure cables
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B7/00—Insulated conductors or cables characterised by their form
    • H01B7/02—Disposition of insulation
    • H01B7/0208—Cables with several layers of insulating material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B7/00—Insulated conductors or cables characterised by their form
    • H01B7/02—Disposition of insulation
    • H01B7/0208—Cables with several layers of insulating material
    • H01B7/0216—Two layers

Definitions

  • This invention relates to electrical equipment employing insulants.
  • the British Patent Specification No. 1 296 032 discloses electrical equipment having a conductor member surrounded by insulants.
  • the insulant comprises finely divided particles of a solid insulating material in an insulating fluid, which fluid acts as a discharge suppressant which is effectively in the form of a thin film as the fluid e.g. mineral fills the space between adjacent particles.
  • the fluid e.g. mineral fills the space between adjacent particles.
  • means are provided for maintaining the fluid above atmospheric pressure and further means are provided for maintaining the interparticle pressure of the insulating material, that is, for applying a pressure to the insulant which limits movement of the particles.
  • Prevention of particle movement ensures that the fluid remains in the form of a thin fluid. Particle movement tends to occur during thermal cycling and limitation of particle movement permits increased current loading.
  • transient electrical strength is that, e.g., during switching and when lightning strikes the electrical equipment.
  • electrical equipment comprising a conductive member surrounded by a taped or extruded insulant in turn surrounded by finely divided particles of solid insulating material in an insulating fluid, which insulating fluid acts as a discharge suppressant and is effectively in the form of a thin film, and means for maintaining the insulating fluid above atmospheric pressure.
  • means for maintaining the interparticle pressure such means apply pressure to the insulant to inhibit particle movement of the insulant.
  • a suitable tape insulant is fused silica tape or polypropelene/paper tape; if an extruded insulant is used it may, for example, be an extrusion of polypropelene or polytetrafluorethylene.
  • the solid insulating material may, for example, be quartz, fused silica, mica, glass or porcelain.
  • the fluid may be a mineral oil, fluorocarbon, silicon oil or sulphur hexafluoride.
  • Maintaining the interparticle pressure has advantages, for example, to inhibit conductor migration through the particle insulant in the case of a cable.
  • the insulation of such a cable may have good thermal conductivity, low dielectric loss and high transient and quiescent electrical strength.
  • the illustrated supertension cable is generally similar to that shown in Figure 2 of British Patent Specification No. 1 296 032 and comprises a stranded cable 1 which is hollow, the duct 2 formed within the conductor 1 being filled with mineral oil under pressure and it will be appreciated that oil from the duct 2 can pass through the stranded conductor 1.
  • the oil pressure in the duct 2 is maintained by a pump connected to the duct.
  • the conductor 2 is surrounded by an oil permeable membrane 3 which may consist of paper tape wound onto the conductor 1; the membrane 4 has wound onto it a layer of fused silica tape 4, the tape 4 having a thickness of 100 to 130 microns.
  • a concentric membrane 5 surrounds the tape 4, the space therebetween being filled with an insulant 6 comprising finely divided particles of a solid insulating material in mineral oil.
  • the oil from the duct 2 cannot only pass through the stranded conductor 1 and the membrane 3 but can also pass through the layer of tape 4 to reach the insulant 6.
  • the membrane 3 is impermeable to particles and will also act as an electrostatic screen.
  • Membrane 5 is impermeable to oil and particles and is surrounded by an electrostatic screen 7 in turn surrounded by a helically wound layer of metal tape 8; the metal tape which is under tension, exerts an inward radial force on the impermeable membrane 5.
  • the layer of metal tape 8 is surrounded by an impermeable metal sheath 9.
  • a pressure is applied to the mineral oil in the s duct 2 and this extends to the oil in the insulant 6.
  • the inward force of the metal tape 8 provides the interparticle pressure.
  • the oil within the space between the tape 4 and the membrane 5 is maintained in the form of a thin film by the particles and acts as a discharge suppressant.
  • the particles may be of any shape but in many applications are desirably spherical for ease of composition.
  • the layer of metal tape may be replaced by a space containing oil under pressure as in Figure 1 of British Patent Specification No. 1 296 032.
  • the provision of the layer of fused silica tape in the region of high electrical stress increases the electrical strength under transient voltages and the use of silica tape as opposed to tapes of organic material has the advantage of relatively great thermal conductivity.
  • the layer of fused silica tape may be replaced by an extruded insulant.
  • An extruded insulant is normally impervious to oil and consequently it will be necessary to connect an oil pump to the space between the membrane 5 and the extruded insulant.
  • the invention is applicable to electrical equipment other than a cable, for example, a transformer bushing and any two electrical member construction which is asymmetrical.
  • a bushing in accordance with this invention may comprise a conductor surrounded by a casing and a corona shield of sheath material which surrounds the central part of the conductor and is secured to the casing so as to define a space which is filled with the fluid which acts as a discharge suppressant, above atmospheric pressure, the remainder of the space within the casing being filled with the said insulant, there being formed a passage permeable to the said fluid but not to the particles of insulating material between the first mentioned space and the remainder of the space within the casing.
  • the particle and fluid insulant is electrically isotropic which has certain advantages in electrical equipment where the electrical stress departs from the radial direction.
  • this has the advantage in the jointing and terminating of transmission cables providing economy in length of the accessory since such a composite being isotropic in nature can tolerate axial stresses within the accessory greater than those which are tolerable using a taped construction.

Landscapes

  • Organic Insulating Materials (AREA)
EP79302793A 1978-12-11 1979-12-05 Equipement électrique utilisant des isolants Withdrawn EP0012560A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB4796478 1978-12-11
GB7847964 1978-12-11

Publications (1)

Publication Number Publication Date
EP0012560A1 true EP0012560A1 (fr) 1980-06-25

Family

ID=10501649

Family Applications (1)

Application Number Title Priority Date Filing Date
EP79302793A Withdrawn EP0012560A1 (fr) 1978-12-11 1979-12-05 Equipement électrique utilisant des isolants

Country Status (2)

Country Link
EP (1) EP0012560A1 (fr)
JP (1) JPS55126911A (fr)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1969720A (en) * 1932-12-21 1934-08-14 Okonite Callender Cable Co Inc Electric power cable
US2532152A (en) * 1944-02-25 1950-11-28 Comp Generale Electricite Thin paper insulated electric cable
FR1011806A (fr) * 1949-03-24 1952-06-27 Electro Cable Soc Câble à haute tension et son procédé de fabrication
US2658939A (en) * 1948-07-29 1953-11-10 Anaconda Wire & Cable Co Power cable containing fluid under pressure
GB1296032A (fr) * 1968-10-22 1972-11-15

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1969720A (en) * 1932-12-21 1934-08-14 Okonite Callender Cable Co Inc Electric power cable
US2532152A (en) * 1944-02-25 1950-11-28 Comp Generale Electricite Thin paper insulated electric cable
US2658939A (en) * 1948-07-29 1953-11-10 Anaconda Wire & Cable Co Power cable containing fluid under pressure
FR1011806A (fr) * 1949-03-24 1952-06-27 Electro Cable Soc Câble à haute tension et son procédé de fabrication
GB1296032A (fr) * 1968-10-22 1972-11-15

Also Published As

Publication number Publication date
JPS55126911A (en) 1980-10-01

Similar Documents

Publication Publication Date Title
US5606149A (en) Closure for high voltage cable connections having an insulating gel to form gel to gel interface with other insulating gel
US10355470B2 (en) Cable fitting for connecting a high-voltage cable to a high-voltage component
US5936825A (en) Rise pole termination/arrestor combination
US2322702A (en) Shielded cable
US3796821A (en) High voltage cable termination
US3585274A (en) Relief of dielectric stress in high voltage cable connections
JPH0715310Y2 (ja) 端末処理された高電圧ケーブル
JPS62254319A (ja) ストレス勾配緩和装置およびその製造方法
WO2006049567A1 (fr) Isolateur de traversee et son procede de fabrication
JP2771505B2 (ja) 直流ブッシング
EP0571386A1 (fr) Terminaison de cable electrique a haute tension et a haute intensite comprenant un seul empilement de condensateurs de calibrage
US4418240A (en) Electrical stress control electrode in combination with a junction end of a shielded insulated electrical conductor
US3843830A (en) Electric cable with corrugated sheath and semi-conductive protective layer between the sheath and the core
US3539706A (en) Thermal expansion resistant cable accessory installation for heavy current electric cables
US3551582A (en) Accessories for cables carrying very heavy currents
EP0012560A1 (fr) Equipement électrique utilisant des isolants
Mackevich et al. Insulation enhancement with heat-shrinkable components. III. Shielded power cable
CN110235208B (zh) 中压和高压线缆应用的多层应力控制制品及干式接线端
US3792191A (en) Enclosure for conductor of electrical transmission system
US3617606A (en) Shielded bushing construction
US4454375A (en) Power cable joint structure having sheath isolation member containing electrode spheres
JP2753097B2 (ja) ガス絶縁機器
US2401996A (en) Cable terminal
US3080447A (en) Inorganic shielded cable termination system
JPS6036981Y2 (ja) ガス絶縁機器の粒子捕捉器

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Designated state(s): DE FR GB IT

17P Request for examination filed
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19820507

RIN1 Information on inventor provided before grant (corrected)

Inventor name: BURTON, EDWARD ARTHUR