Patent US2964950A successfully refreshed from Google Patents.
Patent US4255784A successfully refreshed from Google Patents.
US4255784A
Expired / Lapsed
US
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Transformer-rectifier apparatus
Assignee: Northrop Grumman Corp
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Filing: 1979-11-08
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Granted: 1981-03-10
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Expires: 1999-11-08
Abstract
Abstract A three-phase transformer having a delta-connected primary and two identical secondary windings per phase connected in hexagon, has symmetrical taps on each secondary winding connected to rectifying devices for generating DC energy from a first group of six symmetrical AC voltages at 60 DEG with respect to the virtual neutral for one polarity and from a second group of six symmetrical AC voltages at 60 DEG with respect to the virtual neutral for the other polarity, the first and second groups being at 30 DEG phase shift to one another.
Inventors
- 👤 John Rosa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 07:59
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/02; H02M7/04; H02M7/12; H02M7/145; H02M7/155; H02M7/1552
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
153 words
In a system for converting three-phase alternating current (AC) power into direct current (DC) derived between a positive and a negative DC output terminal, the combination of: a transformer having, (1) three primary windings connected to the respective phases of said AC power; (2) six identical secondary windings connected into a closed regular hexagon, with two secondary windings for one primary winding; (3) a total of twelve taps on said secondary windings distributed at substantially identical central angles on said regular hexagon, with a pair of taps for each secondary winding; a rectifier circuit having twelve rectifier devices operatively connected in two groups, one positive group to the positive DC output terminal and one negative group to the negative DC output terminal; with one tap of each pair of taps of a winding being associated with one rectifier of one group, the other tap being associated with a rectifier of the other group.
Claim 2
Dependent Claim
153 words
In a system for converting three-phase alternating current (AC) power into direct current (DC) derived between a positive and a negative DC output terminal, the combination of: a transformer having, (1) three primary windings connected to the respective phases of said AC power; (2) six identical secondary windings connected into a closed regular hexagon, with two secondary windings for one primary winding; (3) a total of twelve taps on said secondary windings distributed at substantially identical central angles on said regular hexagon, with a pair of taps for each secondary winding; a rectifier circuit having twelve rectifier devices operatively connected in two groups, one positive group to the positive DC output terminal and one negative group to the negative DC output terminal; with one tap of each pair of taps of a winding being associated with one rectifier of one group, the other tap being associated with a rectifier of the other group.
Claim 3
Dependent Claim
21 words
The system of claim 1 with each one of said primary windings being wound coaxially between the associated two secondary windings.
Claim 4
Dependent Claim
34 words
The system of claim 1 with said taps of a pair defining substantially a √3 tan 15° ratio between the symmetrically tapped turns and the total number of turns of the associated secondary winding.
Claim 5
Dependent Claim
31 words
The system of claim 1 with the number of turns of each of said secondary windings being to the section of symmetrically tapped turns in the ratio of eleven to five.
Claim 6
Dependent Claim
31 words
The system of claim 1 with the number of turns of each of said secondary windings being to the section of symmetrically tapped turns in the ratio of fifteen to seven.
Claim 7
Dependent Claim
31 words
The system of claim 1 with the number of turns of each of said secondary windings being to the section of symmetrically tapped turns in the ratio of nineteen to nine.
Claim 8
Dependent Claim
31 words
The apparatus of claim 1 with the number of section of symmetrically turns of each of said secondary windings being to the tapped turns in the ratio of twenty-three to eleven.
Claim 9
Dependent Claim
31 words
The system of claim 1 with the number of turns of each of said secondary windings being to the section of symmetrically tapped turns in the ratio of twenty-six to twelve.
Claim 10
Dependent Claim
14 words
The system of claim 1 with each of said rectifier devices being a diode.
Claim 11
Dependent Claim
14 words
The system of claim 1 with each of said rectifier devices being a thyristor.
Claim 12
Dependent Claim
48 words
The system of claim 10 with at least one thyristor device being associated with one tap of a pair and one DC output terminal, the other tap of a pair being associated with the other DC output terminal through a diode device, thereby to form a semiconverter system.
Claim 13
Dependent Claim
17 words
The apparatus of claim 10 or 11 with means for controlling the firing angle of each thyristor.
Claim 14
Dependent Claim
141 words
In a system for converting three-phase alternating current (AC) power into direct current (DC) derived between a positive and a negative DC output terminal, the combination of: three identical transformers each having, (1) one primary winding connected to one of the respective phases of said AC power; (2) two identical secondary windings; (3) two symmetrically disposed taps on said secondary windings with said secondary windings being connected from one transformer to another so as to form a regular hexagon; a rectifier circuit having twelve rectifier devices operatively connected in two groups, one positive group to the positive DC output terminal and one negative group to the negative DC output terminal; with one tap of each pair of taps of a winding being associated with one rectifier of one group, the other tap being associated with a rectifier of the other group.
Claim 15
Dependent Claim
141 words
In a system for converting three-phase alternating current (AC) power into direct current (DC) derived between a positive and a negative DC output terminal, the combination of: three identical transformers each having, (1) one primary winding connected to one of the respective phases of said AC power; (2) two identical secondary windings; (3) two symmetrically disposed taps on said secondary windings with said secondary windings being connected from one transformer to another so as to form a regular hexagon; a rectifier circuit having twelve rectifier devices operatively connected in two groups, one positive group to the positive DC output terminal and one negative group to the negative DC output terminal; with one tap of each pair of taps of a winding being associated with one rectifier of one group, the other tap being associated with a rectifier of the other group.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-03-09 | 1984-09-08 | 1985-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-09 | 1988-09-08 | 1989-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-09 | 1992-09-08 | 1993-03-10 | $7700.00 | Window Closed / Lapsed |