US3684991A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electromagnetic induction apparatus
Assignee: High Voltage Power Corp
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Filing: 1971-07-12
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Granted: 1972-08-15
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Expires: 1991-07-12
Abstract
Abstract Electromagnetic induction apparatus for high-voltage, high-power operation, using a compact interrupted magnetic circuit whose materials and geometry are so designed as to confine magnetic flux to the compact geometry associated with the magnetic circuit, to confine operating electric currents to windings which cooperate in forming the magnetic circuit, and to distribute both normal and transient voltages quickly and evenly along both the winding and the magnetic circuit so that the electric field strength of the system is maintained high. The apparatus may be applied to either the transformer or the reactor function, but in either event the purpose and advantages of the invention generally relate to so-called large power operation (above ten megavolt amperes) at voltages in the EHV and UHV levels. EACH ODDDDZ0Dsre etdDDD)s nDDDE
Inventors
- 👤 John George Trump
- 👤 Brian Skillicorn
- 👤 Bryon Lee Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:07
CPC Classifications
H; H01; H01F; H01F27/00; H01F27/33; H01F27/28; H01F27/32; H01F27/324; H01F27/34; H01F27/343; H01F27/346; H01F30/00; H01F30/02; H01F30/06; H01F30/12
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
238 words
Electromagnetic induction apparatus for high-voltage, highpower operation at a voltage V comprising a tank containing insulating fluid and, mounted therein, the following elements: a. at least two magnetic columns each having a first end plane, a second end plane, a midplane and a high-voltage terminal in said midplane b. a first magnetic yoke magnetically connecting said first end planes c. a second magnetic yoke magnetically connecting said second end planes each of said magnetic columns comprising a series of similar core elements separated by a series of n similar electrically insulating layers each of said core elements being composed of a laminate of ferromagnetic strips separated by insulation of a thickness sufficient only to prevent eddy currents, each of said similar electrically insulating layers having a thickness capable of supporting a voltage of at least 2V/n, d. at least one winding surrounding each of said magnetic columns and having a midpoint which is connected to said highvoltage terminal, said winding being electrically connected to each of said core elements at respective neighboring portions thereof so that the electric potential of each core element is maintained close to the potential of that portion of the winding nearest to the core element in question, whereby said winding may be and therefore is wound in proximity to said magnetic column and e. high voltage bushing means providing a conductive path between each high-voltage terminal and the region external to said tank.
Claim 2
Dependent Claim
238 words
Electromagnetic induction apparatus for high-voltage, highpower operation at a voltage V comprising a tank containing insulating fluid and, mounted therein, the following elements: a. at least two magnetic columns each having a first end plane, a second end plane, a midplane and a high-voltage terminal in said midplane b. a first magnetic yoke magnetically connecting said first end planes c. a second magnetic yoke magnetically connecting said second end planes each of said magnetic columns comprising a series of similar core elements separated by a series of n similar electrically insulating layers each of said core elements being composed of a laminate of ferromagnetic strips separated by insulation of a thickness sufficient only to prevent eddy currents, each of said similar electrically insulating layers having a thickness capable of supporting a voltage of at least 2V/n, d. at least one winding surrounding each of said magnetic columns and having a midpoint which is connected to said highvoltage terminal, said winding being electrically connected to each of said core elements at respective neighboring portions thereof so that the electric potential of each core element is maintained close to the potential of that portion of the winding nearest to the core element in question, whereby said winding may be and therefore is wound in proximity to said magnetic column and e. high voltage bushing means providing a conductive path between each high-voltage terminal and the region external to said tank.
Claim 3
Dependent Claim
47 words
Apparatus according to claim 1, wherein the electric potential of each part of said winding is always in the vicinity of the electric potential of that core element nearest the part in question, whereby said winding may be and therefore is wound closely about said magnetic column.
Claim 4
Dependent Claim
42 words
Apparatus according to claim 1, wherein the mutually opposed surfaces of adjacent core elements are spaced apart by a distance which is uniform over said surfaces except in the peripheral regions thereof, and which, in said peripheral regions, increases towards the exterior.
Claim 5
Dependent Claim
29 words
Apparatus according to claim 1, wherein adjacent metal strips in each of said laminated core elements are connected by conductive means occupying a negligible portion of the inter-strip gap.
Claim 6
Dependent Claim
73 words
Apparatus according to claim 1, wherein said winding constitutes two parallel power circuits for each magnetic column, and said high voltage terminal consists of a conducting member in the midplane of each magnetic column and conDuctively connected to the midpoint of said winding for the purpose of distributing more uniformly both surge and a-c voltages over the winding and magnetic columns while at the same time suppressing eddy currents in said distributing means.
Claim 7
Dependent Claim
73 words
Apparatus according to claim 1, wherein said high voltage terminal is a thin planar conductive, but eddy-current-suppressing element and therefore has low shunt capacitance to ground and high capacitance to the winding on either side so that the distribution of surge voltages lengthwise along said magnetic columns and their surrounding windings is rendered more uniform because of the cominance of series capacitances along the column with respect to the shunt capacitances to ground.
Claim 8
Dependent Claim
49 words
Apparatus according to claim 1, wherein at least one conductive lead is connected to the winding at a point removed from the high voltage end for the purpose of measuring the potential of the high voltage terminal or for transferring electric power at a correspondingly lesser voltage or both.
Claim 9
Dependent Claim
73 words
Apparatus according to claim 1, wherein said high voltage terminal comprises a thin planar conductive but eddy-current-suppressing element supported in the midplane of each magnetic column and wherein said high voltage terminal is connected to the junction of said high voltage bushing and said midpoint of said winding and therefore possesses a high series capacitance to the portion of the winding and magnetic column on either side with low shunt capacitance to ground.
Claim 10
Dependent Claim
25 words
Apparatus according to claim 1 wherein said magnetic columns and said surrounding windings are subjected to compression forces from said first and second magnetic yokes.
Claim 11
Dependent Claim
33 words
Apparatus according to claim 9 wherein said magnetic columns and said surrounding windings are subjected to compression forces from said first and second magnetic yokes but are otherwise mechanically independent of each other.
Claim 12
Dependent Claim
49 words
Apparatus according to claim 10 wherein the electrical insulating layers are predominately composed of dielectric material of Young''s modulus in excess of 106 pounds per square inch but are covered on each surface subjected to compressive forces by a negligible thickness of dielectric material of relatively lower Young''s modulus.
Claim 13
Dependent Claim
42 words
Apparatus according to claim 4 wherein said laminated core elements constitutes a low impedance equi-potential plane with negligable eddy-current loss under high a-c magnetic flux densities which distributes both operating and transient voltages uniformly over the surfaces of abutting electrically insulating layers.
References Cited (Backward Citations)
GB315372A
Cited
GB390500A
Cited
DE732281C
Cited
US2456941A
Cited
US2909742A
Cited
US2945913A
Cited
US3173115A
Cited
US3292127A
Cited
US3274526A
Cited
US3151304A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-15 | 1976-02-14 | 1976-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-15 | 1980-02-14 | 1980-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-15 | 1984-02-14 | 1984-08-15 | $7700.00 | Window Closed / Lapsed |