EP4576144B1 - Laststufenschalter mit befestigungselement - Google Patents

Laststufenschalter mit befestigungselement

Info

Publication number
EP4576144B1
EP4576144B1 EP23220104.6A EP23220104A EP4576144B1 EP 4576144 B1 EP4576144 B1 EP 4576144B1 EP 23220104 A EP23220104 A EP 23220104A EP 4576144 B1 EP4576144 B1 EP 4576144B1
Authority
EP
European Patent Office
Prior art keywords
bushing
housing body
resilient member
load tap
tap changer
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.)
Active
Application number
EP23220104.6A
Other languages
English (en)
French (fr)
Other versions
EP4576144A1 (de
Inventor
Jean Louis Gérard Mathae
Thomas Eriksson
Daniel FORSMAN
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.)
Hitachi Energy Ltd
Original Assignee
Hitachi Energy 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 Hitachi Energy Ltd filed Critical Hitachi Energy Ltd
Priority to EP23220104.6A priority Critical patent/EP4576144B1/de
Priority to PCT/EP2024/086366 priority patent/WO2025132116A1/en
Priority to CN202480068848.XA priority patent/CN122122686A/zh
Priority to KR1020267010537A priority patent/KR20260052205A/ko
Publication of EP4576144A1 publication Critical patent/EP4576144A1/de
Application granted granted Critical
Publication of EP4576144B1 publication Critical patent/EP4576144B1/de
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • 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
    • H01H9/0005—Tap change devices
    • H01H9/0044—Casings; Mountings; Disposition in transformer housing
    • 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
    • H01H9/0005—Tap change devices
    • H01H9/0044—Casings; Mountings; Disposition in transformer housing
    • H01H2009/005—Details concerning the sealing of the oil filled casings

Definitions

  • the present invention relates to improvements to fasteners between members of an on-load tap changer (OLTC). Specifically, the invention relates to fasteners for OLTCs designed for use in moving working conditions, such as at sea.
  • OLTC on-load tap changer
  • On-load tap changers typically comprise a housing formed by a housing body having opposite open ends, each end being closed by a respective lid attached to the housing body using fasteners.
  • the housing body may be made from a rigid material, such as a fiber-reinforced plastic material.
  • EP 01 03 299 A1 describes a cylindrical oil vessel for tap switches in tapped transformers, featuring an insulating cylinder that carries outer terminal and output contacts.
  • the base part includes shaped-on eyelets through which tie bolts are passed and anchored in the output contacts seated in the cylinder wall.
  • the disclosed design focuses on a rigid structural assembly using tie bolts, output contacts, and a sealed interface between the base and the insulating cylinder. Accordingingly, it is an object of the invention to make the OLTC more robust.
  • the object is achieved by an OLTC according to claim 1, with alternative embodiment defined in the dependent claims.
  • the OLTC comprises a housing, said housing comprising a housing body and a metal body attached to the housing body using a plurality of fasteners.
  • Each respective one of said fasteners comprises: a bolt configured to extend from an outside of the housing body, through a respective hole of the housing body, and to engage with a threaded hole of the metal body on an inside of the housing body.
  • the fastener further comprises a bushing inserted in the respective hole of the housing body, said bushing comprising a central opening through which the bolt extends.
  • the bushing provides a smooth interface towards the bolt which mitigates abrasion on the bolt whilst the larger outer diameter of the bushing provides an enlarged wear surface facing the housing body.
  • a resilient member such as rubber or an elastomer, is provided between the bushing and the housing body and is configured to align the bushing with the respective hole of the housing body.
  • the resilient member enables proper alignment of the bushing with respect to the housing body whilst enabling relative movement between the bushing and the housing body.
  • the bushing may extend into a respective recess of the metal body, said recess extending around each respective threaded hole in the metal body and said recess being configured to provide a tight fit with the bushing.
  • the bushing extends into the recess of the metal body, and since the bushing has a tight fit with the recess, relative movements between the bushing and the metal body are prevented, which in turn reduces relative movement between the bolt and the bushing, thus reducing wear on the bolt.
  • the metal body may be a lid configured to cover an open end of the housing body.
  • one lid is typically provided at each open end of the housing body.
  • the fasteners are able to attach any metal member component to the housing body.
  • the resilient member may be attached to the bushing using moulding or vulcanization.
  • the resilient member may alternatively be attached to the housing body on a radial circumference of the respective hole of the housing body.
  • Affixing the resilient member to either the bushing or the housing body enables more exact positioning of the resilient member and reduces the risk of misplacing the resilient member at manufacturing or maintenance of the OLTC.
  • the bushing may be provided with a circumferential recess, wherein the resilient member extends into said recess and protrudes radially outside of the recess with respect to a central axis of the bolt.
  • the radially protruding portion of the resilient member will deform elastically upon relative movements between the bushing and the metal member. Since the resilient member extends into the circumferential recess, a portion of the resilient member within the circumferential recess will also deform, allowing greater movement of the protruding portion of the resilient member, which in turn enables use of a tougher material of the resilient member, thus increasing resistance to wear of the resilient member.
  • the resilient member may be formed by a gasket, such as an O-ring or cylindrical member.
  • the bushing may be made of an electrically conductive material.
  • the electrical conductivity of the bushing enables the bushing to improve distribution of an electric field extending by the bolt/bushing.
  • the bushing may comprise a collar extending around a head of the bolt.
  • the collar protects a head of the bolt from wear and tear and if the collar is made from an electrically conductive material, the electrically conductive properties of the bushing 6 enables the collar to improve distribution of an electric field extending by the bolt/bushing.
  • Figs. 2 and 4-12 are cross-sectional views.
  • the OLTC comprises a housing, said housing comprising a housing body 2 and a metal body 3 attached to the housing body 2 using a plurality of fasteners 4.
  • Each respective one of said fasteners 4 comprises: a bolt 5 configured to extend from an outside of the housing body 2, through a respective hole of the housing body 2, and to engage with a threaded hole of the metal body 3 on an inside of the housing body 2.
  • the fastener 4 further comprises a bushing 6 inserted in the respective hole of the housing body 2, said bushing 6 comprising a central opening through which the bolt 5 extends.
  • the bushing 6 comprises a collar 7 extending around a head of the bolt 5.
  • the collar 7 protects the head of the bolt 5, thereby making subsequent service of the OLTC 1 easier by ensuring the bolt head is not damaged and can thus be easily rotated.
  • the collar 7 may optionally be omitted.
  • the bushing 6 provides a smooth interface towards the bolt 5 which mitigates abrasion on the bolt 5 whilst the larger outer diameter of the bushing 6 provides an enlarged wear surface facing the housing body 2.
  • the bushing 6 is made of an electrically conductive material.
  • the electrically conductive properties of the bushing 6 enables the collar 7 to improve distribution of an electric field extending by the bolt 5/bushing 6.
  • the screw is made from an isolation material, such as a ceramic material or a fibre-composite material, a collar is typically not needed on the bushing.
  • the bushing 6 may extend into a respective recess 9 of the metal body 3, said recess 9 extending around each respective threaded hole in the metal body 3 and said recess 9 being configured to provide a tight fit with the bushing 6.
  • the bushing 6 may optionally instead not engage with a recess of the metal member 3.
  • the metal body 3 is a lid of the OLTC 1 configured to cover an open end of the housing body 2.
  • the metal body 3 may be any member of the OLTC 1 attached to the housing body 2, such as a bracket or frame.
  • a resilient member 8 such as rubber or an elastomer, is, in any embodiment provided between the bushing 6 and the housing body 2.
  • the resilient member 8 is configured to align the bushing 6 with the respective hole of the housing body 2.
  • the resilient member 8 enables proper alignment of the bushing with respect to the housing body 2 whilst enabling relative movement between the bushing and the housing body 2.
  • dynamic loading conditions on the OLTC typically occurring when used at sea, may be absorbed without excessive internal stress on or around fasteners.
  • higher tolerances may be used at production of the OLTC 1 without affecting assembly of the OLTC 1 negatively.
  • the resilient member 8 may be attached to the bushing 6 using moulding or vulcanization. As shown in fig. 10 , the resilient member 8 may alternatively be attached to the housing body 2 on a radial circumference of the respective hole of the housing body 2.
  • Affixing the resilient member to either the bushing 6 or the housing body 2 enables more exact positioning of the resilient member 8 and reduces the risk of misplacing the resilient member 8 at manufacturing or maintenance of the OLTC 1.
  • the bushing 6 may be provided with a circumferential recess 10, wherein the resilient member 8 extends into said recess 10 and protrudes radially outside of the recess 10 with respect to a central axis of the bolt 5.
  • the radially protruding portion of the resilient member 8 will deform elastically upon relative movements between the bushing 6 and the metal member 3. Since the resilient member 8 extends into the circumferential recess 10, a portion of the resilient member 8 within the circumferential recess 10 will also deform, allowing greater movement of the protruding portion of the resilient member 8, which in turn enables use of a tougher material of the resilient member 8, thus increasing resistance to wear of the resilient member 8.
  • the resilient member 8 may be formed by any suitable gasket, such as an O-ring or cylindrical member.
  • the resilient member 8 may be provided with geometries for engaging with corresponding geometries formed on the bushing 6 and/or on the housing body 2, thus improving alignment of the resilient member 8 with the bushing 6 and/or with the housing body 2.
  • the invention is not limited to the specific combination of features illustrated in the examples of the appended figures.
  • the recess of the metal body 3 receiving an end of the bushing 6 (examples in figs. 4 and 7-12 ) may be omitted from any of the embodiments in figs. 4 and 7-12
  • the collar 7 omitted in fig. 12 may be omitted in any embodiment of the bushing 6.
  • a washer is typically used between the head of the bolt 5 and the bushing, although that washer may be omitted.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Insulators (AREA)

Claims (9)

  1. Laststufenschalter (1), der ein Gehäuse umfasst, wobei das Gehäuse einen Gehäusekörper (2) und einen Metallkörper (3) umfasst, der unter Verwendung mehrerer Befestigungselemente (4) an dem Gehäusekörper (2) angebracht ist,
    wobei jedes der Befestigungselemente (4) jeweils Folgendes umfasst:
    einen Bolzen (5), der dazu ausgelegt ist, sich von einer Außenseite des Gehäusekörpers (2) durch ein jeweiliges Loch des Gehäusekörpers (2) zu erstrecken und mit einem Gewindeloch des Metallkörpers (3) auf einer Innenseite des Gehäusekörpers (2) in Eingriff zu kommen, wobei das Befestigungselement (4) ferner eine Durchführung (6) umfasst, die in das jeweilige Loch des Gehäusekörpers (2) eingesetzt ist, wobei die Durchführung (6) eine zentrale Öffnung umfasst, durch die sich der Bolzen (5) erstreckt, dadurch gekennzeichnet, dass ein elastisches Element (8), wie Gummi oder ein Elastomer, zwischen der Durchführung (6) und dem Gehäusekörper (2) bereitgestellt und dazu ausgelegt ist, die Durchführung (6) mit dem jeweiligen Loch des Gehäusekörpers (2) auszurichten.
  2. Laststufenschalter (1) nach Anspruch 1, wobei sich die Durchführung (6) in eine jeweilige Aussparung (9) des Metallkörpers (3) erstreckt, wobei sich die Aussparung (9) jeweils um jedes Gewindeloch in dem Metallkörper (3) erstreckt und die Aussparung (9) dazu ausgelegt ist, einen festen Sitz mit der Durchführung (6) bereitzustellen.
  3. Laststufenschalter (1) nach einem der Ansprüche 1-2, wobei der Metallkörper (3) ein Deckel ist, der dazu ausgelegt ist, ein offenes Ende des Gehäusekörpers (2) abzudecken.
  4. Laststufenschalter (1) nach einem der Ansprüche 1-3, wobei das elastische Element (8) unter Verwendung von Formpressen oder Vulkanisierung an der Durchführung (6) angebracht ist.
  5. Laststufenschalter (1) nach einem der Ansprüche 1-3, wobei das elastische Element (8) auf einem radialen Umfang des jeweiligen Lochs des Gehäusekörpers (2) an dem Gehäusekörper (2) angebracht ist.
  6. Laststufenschalter (1) nach Anspruch 5, wobei die Durchführung (6) mit einer umlaufenden Aussparung (10) versehen ist, und wobei sich das elastische Element (8) in die Aussparung (10) erstreckt und in Bezug auf eine Mittelachse des Bolzens (5) radial an einer Außenseite der Aussparung (10) hervorsteht.
  7. Laststufenschalter (1) nach einem der Ansprüche 1-3, wobei das elastische Element (8) durch eine Dichtung, wie etwa einen O-Ring oder ein zylindrisches Element, ausgebildet ist.
  8. Laststufenschalter (1) nach einem der Ansprüche 1-7, wobei die Durchführung (6) aus einem elektrisch leitfähigen Material besteht.
  9. Laststufenschalter (1) nach einem der Ansprüche 1-8, wobei die Durchführung (6) einen Kragen (7) umfasst, der sich um einen Kopf des Bolzens (5) erstreckt.
EP23220104.6A 2023-12-22 2023-12-22 Laststufenschalter mit befestigungselement Active EP4576144B1 (de)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP23220104.6A EP4576144B1 (de) 2023-12-22 2023-12-22 Laststufenschalter mit befestigungselement
PCT/EP2024/086366 WO2025132116A1 (en) 2023-12-22 2024-12-13 An on-load tap changer comprising a fastener
CN202480068848.XA CN122122686A (zh) 2023-12-22 2024-12-13 具有紧固件的有载分接开关
KR1020267010537A KR20260052205A (ko) 2023-12-22 2024-12-13 패스너를 포함하는 부하시 탭 절환기

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP23220104.6A EP4576144B1 (de) 2023-12-22 2023-12-22 Laststufenschalter mit befestigungselement

Publications (2)

Publication Number Publication Date
EP4576144A1 EP4576144A1 (de) 2025-06-25
EP4576144B1 true EP4576144B1 (de) 2026-08-12

Family

ID=89322008

Family Applications (1)

Application Number Title Priority Date Filing Date
EP23220104.6A Active EP4576144B1 (de) 2023-12-22 2023-12-22 Laststufenschalter mit befestigungselement

Country Status (4)

Country Link
EP (1) EP4576144B1 (de)
KR (1) KR20260052205A (de)
CN (1) CN122122686A (de)
WO (1) WO2025132116A1 (de)

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD159687A1 (de) * 1981-06-16 1983-03-23 Helmut Kuntzsch Oelgefaess fuer lastumschalter von stufenschaltern
DE3234213C2 (de) * 1982-09-15 1985-10-17 Maschinenfabrik Reinhausen Gebrüder Scheubeck GmbH & Co KG, 8400 Regensburg Zylindrisches Ölgefäß für Stufenschalter von Stufentransformatoren
DE4435358C2 (de) * 1994-09-20 2003-05-08 Siemens Ag Polsäule eines Hochspannungs-Leistungsschalters

Also Published As

Publication number Publication date
KR20260052205A (ko) 2026-04-17
CN122122686A (zh) 2026-05-29
EP4576144A1 (de) 2025-06-25
WO2025132116A1 (en) 2025-06-26

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Inventor name: MATHAE, JEAN LOUIS GERARD

Inventor name: ERIKSSON, THOMAS

Inventor name: FORSMAN, DANIEL