US4600877A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Arrangement in transformers
Assignee: Kraftelektronik AB
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Filing: 1984-09-19
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Granted: 1986-07-15
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Expires: 2004-09-19
Abstract
Abstract In a transformer having a primary winding which is connectable to an a.c. voltage source via switch means which opens and closes at a controllable frequency, there is connected in parallel with the primary or secondary winding of the transformer a circuit which for at least a part of the time during which the switch means opens maintains magnetization of the transformer in a direction opposite to the direction of the magnetization caused by the subsequent closing of the switch means.
Inventors
- 👤 Rolf Soderholm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:35
CPC Classifications
H; H02; H02M; H02M5/00; H02M5/02; H02M5/04; H02M5/22; H02M5/25; H02M5/257; H02P; H02P13/00; H02P13/12
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
95 words
An arrangement for a transformer having a primary winding which is connectable to an a.c. voltage source via a switch means which opens and closes at a controllable frequency in a manner such that said switch means is closed during at least parts of predetermined half-periods of the a.c. voltage separated by a predetermined even number of half-periods of said a.c. voltage, wherein connected in parallel with the primary or secondary winding of the transformer is a circuit which substantially maintains the magnetization of the transformer caused by the previous closing of the switch means.
Claim 2
Dependent Claim
95 words
An arrangement for a transformer having a primary winding which is connectable to an a.c. voltage source via a switch means which opens and closes at a controllable frequency in a manner such that said switch means is closed during at least parts of predetermined half-periods of the a.c. voltage separated by a predetermined even number of half-periods of said a.c. voltage, wherein connected in parallel with the primary or secondary winding of the transformer is a circuit which substantially maintains the magnetization of the transformer caused by the previous closing of the switch means.
Claim 3
Dependent Claim
42 words
An arrangement according to claim 1, wherein said circuit exhibits a high impedance to voltages above a given value and a low impedance to voltages below said value, said value being substantially lower than the output voltage of the a.c. voltage source.
Claim 4
Dependent Claim
24 words
An arrangement according to claim 2, wherein said voltage value lies within the range 2-30% of the output voltage of the a.c. voltage source.
Claim 5
Dependent Claim
24 words
An arrangement according to claim 2, wherein said voltage value lies within the range 3-15% of the output voltage of the a.c. voltage source.
Claim 6
Dependent Claim
50 words
An arrangement according to claim 1, wherein said circuit includes at least one d.c. voltage source which is connectable in series with the primary or secondary winding of the transformer for at least a part of the time during which the switch means is open to drive a current therethrough.
References Cited (Backward Citations)
US4016482A
Cited
US4441146A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-07-14 | 1990-01-13 | 1990-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-07-14 | 1994-01-13 | 1994-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-07-14 | 1998-01-13 | 1998-07-15 | $7700.00 | Window Closed / Lapsed |