US3321725A - Current transformers having multiturn primary windings - Google Patents

Current transformers having multiturn primary windings Download PDF

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Publication number
US3321725A
US3321725A US514221A US51422165A US3321725A US 3321725 A US3321725 A US 3321725A US 514221 A US514221 A US 514221A US 51422165 A US51422165 A US 51422165A US 3321725 A US3321725 A US 3321725A
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US
United States
Prior art keywords
primary
core
transformer
primary conductors
secondary winding
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
US514221A
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English (en)
Inventor
Robert S Canney
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.)
General Electric Co
Original Assignee
General Electric Co
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 General Electric Co filed Critical General Electric Co
Priority to US514221A priority Critical patent/US3321725A/en
Priority to GB44962/66A priority patent/GB1118537A/en
Priority to DE19661563195 priority patent/DE1563195A1/de
Priority to CH1648866A priority patent/CH459353A/de
Priority to FR87218A priority patent/FR1505009A/fr
Application granted granted Critical
Publication of US3321725A publication Critical patent/US3321725A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01FMAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F38/00Adaptations of transformers or inductances for specific applications or functions
    • H01F38/20Instruments transformers
    • H01F38/22Instruments transformers for single phase ac
    • H01F38/28Current transformers
    • H01F38/30Constructions

Definitions

  • the primary winding is in the form of a bar or other conductor extending through a window opening in the cast core and secondary winding unit. These transformers are very satisfactory for their intended use. However, in many current transformers it is necessary to provide a number of turns of the primary winding to obtain the desired ratio of current transformation.
  • a further object of this invention is to provide a current transformer having a multi-turn primary winding which may be adjusted to any of a plurality of ratios.
  • a still further object of this invention is to provide a current transformer having a multi-turn primary winding comprising a plurality of individual conductors which can be terminated in any desired manner to provide any of a plurality of transformer ratios.
  • this invention comprises a current transformer having a core and secondary winding unit encased in a resinous material to form a single unit.
  • a plurality of primary conductors are placed through the window opening of the core and secondary winding unit.
  • a second plurality of primary conductors are placed about the outside of the core and secondary winding unit substantially parallel to the first plurality of primary conductors.
  • End caps are provided, secured to the core and secondary winding unit, holding the primary conductors in the desired position.
  • the entire device is then enclosed in an insulating casting resin to provide a current transformer having a plurality of primary conductors extending from each end thereof.
  • the primary conductors may then be terminated to provide a current transformer of a desired ratio.
  • FIGURE 1 is a perspective view of the transformer portion of a current transformer according to this invention.
  • FIGURE 2 is an exploded perspective view of a current transformer according to a preferred form of this invention prior to casting in an insulated resin;
  • FIGURE 3 is a perspective view of a current transformer according to the preferred embodiment of this invention showing one form of termination of the primary conductors;
  • FIGURES 4 and 5 are end views of each end of a current transformer according to this invention showing one form of termination of the primary conductors to obtain 7 a desired ratio.
  • FIG. 1 of the drawing there is shown the transformer portion 10 of a current transformer having primary terminals 12 and 14 at each end of unit 10. Secondary leads 16 extend from bottom 18 to a secondary terminal box (not shown). As will be understood, transformer 10 is usually mounted on a high voltage bushing (not shown) with the secondary leads 16 brought through such bushing to the secondary terminal box at the bottom of the bushing. The current to be monitored is provided to the transformer ll) through the primary terminals 12 and 14.
  • FIG. 2 of the drawing there is shown an exploded perspective view of one form of the current transformer according to a preferred embodiment of this invention.
  • a cast core and secondary winding unit 20 is shown having a Window opening 22 therein.
  • Secondary leads 16 extend from the bottom of the core and coil unit 20.
  • One group of primary conductors 24 extend through the window opening 22.
  • a second group of primary conductors 26 are preferably formed substantially in a hat-shape, as shown, and are placed around the outside of the core and secondary winding unit 20.
  • a pair of end caps 28, only one being shown in the drawing, are secured to opposite ends of the core and winding unit 20. End caps 28 have a plurality of slots 30 and 32 for receiving primary conductors 24 and 26 respectively.
  • End cap 28 holds conductors 24 and 26 in a predetermined position within and around the core and secondary winding unit 20. End caps 28 are also provided with a plurality of studs 34 for securing a terminating ring 36 and a terminal bell 38 to each end of the transformer 10.
  • the primary conductors 24 and 26 When an order is received for a certain ratio the primary conductors 24 and 26 would be terminated by attaching terminating rings 36 to end caps 28 by means of studs 34, in the manner particularly shown in FIG. 3.
  • One or more tabs 40 are provided on terminating rings 36 and the primary conductors 24 and 26 are secured to the rings 36 and to each other to provide the desired transformer ratio.
  • terminal bells 38 are secured to the ends of the transformer by means of studs 34 providing units substantially as shown in FIG. 1.
  • studs 34 provide an electrical connection betwen terminal bells 38 and terminating rings 36.
  • FIGURES 4 and 5 show an end view of each end of transformer 10, showing one form of termination.
  • twenty-four primary conductors 24 and twenty-four primary conductors 26 are shown.
  • Terminating rings 36 are shown with a single tab 40 to which one of the primary conductors 24 is connected, for example, as by welding.
  • a twenty-four turn primary is provided by connecting all of the primary conductors 24 and 26 in series.
  • a plurality of tabs 40 could be provided and twelve conductors could be connected in parallel to provide a two-turn primary.
  • One advantage of the disclosed construction occurs when testing of the unit discloses a turn-to-turn failure in the primary conductors 24 and 26. This could occur, for example, due to the shifting of conductors 24 and 26 during the casting of the unit in the resinous insulating material.
  • Such transformer having a turn-to-turn failure may still be used by merely selecting a transformer ratio which would place the two turns in parallel. In this manner it is possible to use many transformers which would otherwise either have to be scrapped or else be subjected to expensive re-work.
  • a current transformer having a multi-turn primary winding comprising a core and secondary winding unit having a window opening therein, a first plurality of primary conductors extending through said window opening, a second plurality of primary conductors extending around the outisde of said core and secondary winding unit, end caps secured to opposite ends of said core and secondary winding unit, said end caps provided with slots for receiving said first and said second plurality of primary conductors and holding them in position within and around said core and said secondary winding unit.
  • a current transformer as claimed in claim 1 in which a resinous insulating material is molded about said core and secondary winding unit, said first and said second plurality of primary conductors, and said end caps.
  • a current transformer as claimed in claim 2 in which terminating rings are provided on opposite ends of said core and secondary winding unit for terminating said first and said second plurality of primary conductors to provide a desired ratio.
  • a current transformer as claimed in claim 2 in which said end caps are provided with a plurality of studs, terminating rings are provided being secured to said end caps by said plurality of studs, said terminating rings terminating said first and said second plurality of primary conductors to provide a desired transformer ratio.
  • a current transformer as claimed in claim 3 in which terminal bells are provided on opposite ends of said core and winding unit, said terminal bells secured to said terminating rings and electrically connected thereto, said terminal bells having terminals thereon as the primary terminals of said current transformer.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Transformers For Measuring Instruments (AREA)
US514221A 1965-12-16 1965-12-16 Current transformers having multiturn primary windings Expired - Lifetime US3321725A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US514221A US3321725A (en) 1965-12-16 1965-12-16 Current transformers having multiturn primary windings
GB44962/66A GB1118537A (en) 1965-12-16 1966-10-07 Improvements in current transformers having multi-turn primary windings
DE19661563195 DE1563195A1 (de) 1965-12-16 1966-10-18 Stromwandler
CH1648866A CH459353A (de) 1965-12-16 1966-11-16 Stromwandler
FR87218A FR1505009A (fr) 1965-12-16 1966-12-13 Transformateurs de courant

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US514221A US3321725A (en) 1965-12-16 1965-12-16 Current transformers having multiturn primary windings

Publications (1)

Publication Number Publication Date
US3321725A true US3321725A (en) 1967-05-23

Family

ID=24046290

Family Applications (1)

Application Number Title Priority Date Filing Date
US514221A Expired - Lifetime US3321725A (en) 1965-12-16 1965-12-16 Current transformers having multiturn primary windings

Country Status (5)

Country Link
US (1) US3321725A (de)
CH (1) CH459353A (de)
DE (1) DE1563195A1 (de)
FR (1) FR1505009A (de)
GB (1) GB1118537A (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2409584A1 (fr) * 1977-11-22 1979-06-15 Nippon Kinzoku Co Ltd Bobine de reactance
US5015983A (en) * 1990-06-18 1991-05-14 General Electric Company Compact circuit interrupter having multiple ampere ratings
US20080012675A1 (en) * 2004-08-12 2008-01-17 Epcos Ag Inductive Component For High Currents And Method For The Production Thereof
US20080164968A1 (en) * 2005-02-11 2008-07-10 Feist Guenter Insulation Alement And Toroidal Core Throttle
CN113484800A (zh) * 2021-07-15 2021-10-08 杭州电力设备制造有限公司 一种变压器绕组匝间故障的检测方法、装置、设备及介质

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES435986A1 (es) * 1974-08-21 1976-12-16 Condor Werk Frede Kg Geb Perfeccionamientos introducidos en los interruptores de proteccion contra corriente de defecto.
DE3243274C2 (de) * 1982-10-28 1985-04-04 LGZ Landis & Gyr Zug AG, Zug Vorrichtung für die Anpassung des Meßstromes an ein Meßgerät zur Messung von elektrischen Strömen
DE10160860A1 (de) * 2000-12-12 2002-09-26 Abb Patent Gmbh Stromwandler, vorzugweise für einen Fehlerstrom-Schutzschalter

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2409584A1 (fr) * 1977-11-22 1979-06-15 Nippon Kinzoku Co Ltd Bobine de reactance
US5015983A (en) * 1990-06-18 1991-05-14 General Electric Company Compact circuit interrupter having multiple ampere ratings
DE4119830B4 (de) * 1990-06-18 2006-03-23 General Electric Co. Kompakt-Schalter mit verschiedenen Nennströmen
US20080012675A1 (en) * 2004-08-12 2008-01-17 Epcos Ag Inductive Component For High Currents And Method For The Production Thereof
US8063728B2 (en) 2004-08-12 2011-11-22 Epcos Ag Inductive component for high currents and method for the production thereof
US20080164968A1 (en) * 2005-02-11 2008-07-10 Feist Guenter Insulation Alement And Toroidal Core Throttle
US7990248B2 (en) 2005-02-11 2011-08-02 Epcos Ag Insulation alement and toroidal core throttle
CN113484800A (zh) * 2021-07-15 2021-10-08 杭州电力设备制造有限公司 一种变压器绕组匝间故障的检测方法、装置、设备及介质
CN113484800B (zh) * 2021-07-15 2024-03-08 杭州电力设备制造有限公司 一种变压器绕组匝间故障的检测方法、装置、设备及介质

Also Published As

Publication number Publication date
CH459353A (de) 1968-07-15
FR1505009A (fr) 1967-12-08
GB1118537A (en) 1968-07-03
DE1563195A1 (de) 1969-11-27

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