EP0889487B1 - Bushing insulator with shielding of the electrical field, particularly for medium and high-voltage switchboards - Google Patents

Bushing insulator with shielding of the electrical field, particularly for medium and high-voltage switchboards Download PDF

Info

Publication number
EP0889487B1
EP0889487B1 EP98202137A EP98202137A EP0889487B1 EP 0889487 B1 EP0889487 B1 EP 0889487B1 EP 98202137 A EP98202137 A EP 98202137A EP 98202137 A EP98202137 A EP 98202137A EP 0889487 B1 EP0889487 B1 EP 0889487B1
Authority
EP
European Patent Office
Prior art keywords
shape memory
bushing insulator
metal insert
memory material
shielding
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
EP98202137A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0889487A2 (en
EP0889487A3 (en
Inventor
Antonio Giacomucci
Silvia Volponi
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.)
ABB Power Technologies SpA
Original Assignee
ABB SACE SpA
SACE SpA
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 ABB SACE SpA, SACE SpA filed Critical ABB SACE SpA
Publication of EP0889487A2 publication Critical patent/EP0889487A2/en
Publication of EP0889487A3 publication Critical patent/EP0889487A3/en
Application granted granted Critical
Publication of EP0889487B1 publication Critical patent/EP0889487B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime 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
    • H01B17/00—Insulators or insulating bodies characterised by their form
    • H01B17/26—Lead-in insulators; Lead-through insulators

Definitions

  • bushing insulators such as those for medium-voltage switchboards, for example, generally comprise a moulding of electrical insulating material that separates the grounded metal structure of the electrical equipment from the live conductor and which encloses a metal insert for shielding the electrical field. Said insert has the function of limiting the electrical stresses acting on the distribution of the field lines.
  • the inserts are normally made using a metal mesh that must be able to withstand the mechanical stresses that occur during the phase for moulding the insulating material to avoid deformations that could impact its correct positioning.
  • the task of the invention is precisely to overcome the drawbacks set forth above by making a bushing insulator with shielding of the electrical field to be used, for example, in medium and high-voltage air-insulated switchboards (AIS), gas-insulated switchboards (GIS), medium and high-voltage power transformers and reactance, instrument transformers, capacitors, and medium and high-voltage gas insulated busbar in which it is possible to use metal inserts that, while having a relatively low mass are able to maintain a predetermined shape and position at the moment of moulding, thus achieving the best characteristics from an electrical standpoint.
  • AIS air-insulated switchboards
  • GIS gas-insulated switchboards
  • GIS gas-insulated switchboards
  • VCS medium and high-voltage power transformers and reactance
  • instrument transformers capacitors
  • medium and high-voltage gas insulated busbar in which it is possible to use metal inserts that, while having a relatively low mass are able to maintain a predetermined shape and position at the moment of moulding, thus achieving the
  • one particular object of the invention is to develop a bushing insulator in which any deformations are eliminated with certainty at the moment of moulding, so that the metal insert has the optimal position and shape when the resin is polymerised.
  • a further object of the present invention is to develop a bushing having high reliability and safety in use due to its distinctive constructional characteristics.
  • the last object of the present invention is to develop a bushing insulator that can easily be obtained from commercially available parts and materials and that is, moreover, competitive from a purely economic standpoint.
  • a bushing insulator for shielding an electrical field comprising a moulding of electrical insulating material to be located in a passage hole in an electrical switchboard and enclosing a metal insert for shielding the electrical field.
  • the bushing insulator according to the invention is characterised in that said metal insert comprises a shape memory material capable to assume a predetermined shape upon thermal stress.
  • the bushing insulator with shielding of the electrical field according to the invention comprises a casting 2 of electrical insulating material, that it is preferably made of epoxy resin, which is located in a hole 3 provided in the metal wall of an electrical switchboard, generally indicated by reference number 4.
  • a metal insert is provided around the conductor 5 to be shielded, said metal insert being embedded in the moulding of electrical insulating material.
  • the distinctive feature of the invention is constituted by the fact that said metal insert, which has the function of limiting the electrical stress acting on the distribution of the field lines, is made using shape memory alloys that, when subjected to thermal stress, restore the correct geometry within the material.
  • the shape memory alloys for example alloys such as NiTi, CuAl, CuAlX, where X is Ni, Be, Zn or Mn, and CuZnY, where Y is Al, Si, Sn, Ga or Mn, are characterised by the possibility of restoring their original configuration determined in the design phase when they are subjected to an increase in temperature above a critical transition temperature; these shape memory alloys thus ensure the correct position and shape is restored within the insulator at the moment of moulding the plastic in liquid phase at high temperature.
  • the shape memory metal component in martensite phase is positioned in the moulding simply taking care to fix the insert correctly in the various fixing points, without having to pay any particular attention to the overall position of the insert.
  • the insert At the moment of moulding the liquid resin, at high temperature, the insert begins responding to the thermal stress, actuating the transformation from martensite to austenite phase and thus regaining the original design shape and assuming the predetermined shape that corresponds to the optimal positioning of the metal insert.
  • the response of the shape memory material to the thermal stress which is defined as the time required for the predetermined shape to be restored, is in the order of fractions of a second.
  • the polymerisation time of the resin consequently does not cause any limitation on this restoration of shape.
  • so-called “single shot” shape memory alloys defined as alloys that guarantee perfect functioning for a single operation or for a few operations. Indeed for this type of application it is not necessary for the alloy to be able to execute the restoration of shape more than once, given that the correct position is subsequently held due to the fact that the metal insert remains embedded in the resin moulding.
  • a metal insert is illustrated, indicated by 10a, which is shaped with a toroidal portion and is made using a mesh of shape memory material that enables easier passage of the resin during moulding.
  • Figure 4 illustrates a metal insert, indicated by 10b that is obtained using a foil that is also made of shape memory material.
  • the shape memory material may simply form a part of the metal insert and not necessarily the entire metal insert, provided that the portions used are able to restore -the entire metal insert to its predetermined shape.
  • the insert 10 comprises inserts 10c of shape memory material that are positioned parallel to the axis and extend over the entire circumferential development of the insert.
  • inserts of shape memory alloy indicated by 10d that have an annular configuration and are uniformly distributed.
  • the inserts 10e are positioned so that they cross over one another and are made of shape memory alloy applied to an insert 10 that can have different shapes.
  • the shape memory alloy insert 10f assumes a helical position within a metal insert that can be made in a variety of ways.
  • thermo-mechanical stress that is applied by the liquid resin has a positive effect, since it causes the automatic restoration of the designed shape and consequently of the optimal characteristics of the insert that is always positioned perfectly.
  • traditional shielding undergoes a distortion in the designed shape and consequently has a negative effect.

Landscapes

  • Insulators (AREA)
  • Insulating Bodies (AREA)
  • Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
  • Cable Accessories (AREA)
  • Installation Of Bus-Bars (AREA)
EP98202137A 1997-07-01 1998-06-26 Bushing insulator with shielding of the electrical field, particularly for medium and high-voltage switchboards Expired - Lifetime EP0889487B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT97MI001558A IT1292447B1 (it) 1997-07-01 1997-07-01 Isolatore passante con schermatura del campo elettrico,particolarmente per quadri di media e alta tensione
ITMI971558 1997-07-01

Publications (3)

Publication Number Publication Date
EP0889487A2 EP0889487A2 (en) 1999-01-07
EP0889487A3 EP0889487A3 (en) 1999-02-24
EP0889487B1 true EP0889487B1 (en) 2004-03-03

Family

ID=11377475

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98202137A Expired - Lifetime EP0889487B1 (en) 1997-07-01 1998-06-26 Bushing insulator with shielding of the electrical field, particularly for medium and high-voltage switchboards

Country Status (5)

Country Link
EP (1) EP0889487B1 (da)
AT (1) ATE261179T1 (da)
DE (1) DE69822041T2 (da)
ES (1) ES2217499T3 (da)
IT (1) IT1292447B1 (da)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR200449360Y1 (ko) 2008-10-09 2010-07-05 김태선 부싱용 쉴드
EP4001928A1 (en) * 2020-11-19 2022-05-25 3M Innovative Properties Company Sensored insulation plug

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19547120A1 (de) * 1995-12-16 1997-06-19 Sachsenwerk Ag Elektrode

Also Published As

Publication number Publication date
EP0889487A2 (en) 1999-01-07
ITMI971558A1 (it) 1999-01-01
DE69822041T2 (de) 2005-03-03
EP0889487A3 (en) 1999-02-24
ES2217499T3 (es) 2004-11-01
ATE261179T1 (de) 2004-03-15
ITMI971558A0 (da) 1997-07-01
DE69822041D1 (de) 2004-04-08
IT1292447B1 (it) 1999-02-08

Similar Documents

Publication Publication Date Title
KR101098488B1 (ko) 진공 절연 스위치 기어
US8168909B2 (en) Vacuum switchgear
US6462295B1 (en) High-voltage power circuit breaker comprising an insulating nozzle
EP0889487B1 (en) Bushing insulator with shielding of the electrical field, particularly for medium and high-voltage switchboards
US20040232113A1 (en) Electric switching device for medium or high voltage
CA2542300C (en) Encapsulated fuse with corona shield
US3684995A (en) Electrical bushing assembly
US4280015A (en) High-tension line
US2883448A (en) Insulated clamping means
EP2865058A1 (en) Disk-shaped insulator for gas-insulated switchgear
JPH06325648A (ja) 光ファイバ内蔵碍子
JP2006197730A (ja) 固体絶縁導体
JP2804040B2 (ja) 電気的接続導体
JPH0382305A (ja) ガス絶縁開閉装置
JPH09180562A (ja) 絶縁スペ−サ
EP4345433A1 (en) Switchgear device
Woods et al. Cast epoxy insulation for high voltage switchgear and power transformers
JPH08125242A (ja) 永久電流スイッチ
EP0832492B1 (en) Electric insulator and method for manufacturing the same
JPS5844581Y2 (ja) モ−ルド形乾式変圧器
Feng et al. Enhancement of External Insulation Performance for Vacuum Interrupters by External Shields
Kobari et al. Epoxy insulation for completely solid insulated compact switchgear with vacuum interrupter
JPH0749690Y2 (ja) 碍子，碍管の破損防止装置
SU1690088A1 (ru) Статор электрической машины переменного тока
JPH0224927A (ja) 断路器

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

Kind code of ref document: A2

Designated state(s): AT BE CH DE DK ES FI FR GB IT LI NL SE

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17P Request for examination filed

Effective date: 19990805

AKX Designation fees paid

Free format text: AT BE CH DE DK ES FI FR GB IT LI NL SE

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

17Q First examination report despatched

Effective date: 20011130

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT BE CH DE DK ES FI FR GB IT LI NL SE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20040303

Ref country code: LI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20040303

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20040303

Ref country code: CH

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20040303

Ref country code: BE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20040303

Ref country code: AT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20040303

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REF Corresponds to:

Ref document number: 69822041

Country of ref document: DE

Date of ref document: 20040408

Kind code of ref document: P

RAP2 Party data changed (patent owner data changed or rights of a patent transferred)

Owner name: ABB POWER TECHNOLOGIES S.P.A.

NLT2 Nl: modifications (of names), taken from the european patent patent bulletin

Owner name: ABB POWER TECHNOLOGIES S.P.A.

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20040603

Ref country code: DK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20040603

NLV1 Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act
REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2217499

Country of ref document: ES

Kind code of ref document: T3

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20041206

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 20080627

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20080624

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20080620

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20080613

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20080620

Year of fee payment: 11

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20090626

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20100226

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20090630

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20090626

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20100101

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20090627

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20090627

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20090626