US3876923A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Inverter paralleling for harmonic reduction
Assignee: Reliance Electric Co
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Filing: 1973-11-28
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Granted: 1975-04-08
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Expires: 1993-11-28
Abstract
Abstract The invention describes a means for reducing the harmonic content of two or more paralleled polyphase inverters by displacing the phase relationship of the outputs of these inverters and connecting them through intervening reactors to a load circuit, which may be a motor or an output transformer, whose windings are phase displaced by the same amount as the inverter outputs. The load circuit includes a load winding with phase and auxiliary windings on one common magnetic circuit. The phase and auxiliary windings are conductively connected to each other and to two sets of terminals of the load winding so that the voltage on one terminal set is phase displaced from the voltage on the other terminal set by an angle corresponding to the phase displacement between the inverter outputs.
Inventors
- 👤 Andrew J Humphrey
- 👤 James W A Wilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:18
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/497
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
173 words
A load circuit for operation with a first and a second power converter wherein the output of the first converter has a phase angle relative to the output of the second converter, comprising in combination: a load winding having a phase winding for each phase of one of the converters and having inductively coupled auxiliary winding means on one common magnetic circuit; first terminal means of said load winding having terminals equal in number to the phases of the first converter; second terminal means of said load winding having terminals equal in number to the phases of the second converter; means connected between the first and second converters and said first and second terminal means, respectively, for absorbing voltage differences; and means for conductively connecting said phase and auxiliary winding means to each other and to said terminal means to have said first terminal means of said conductively connected load winding electrically displaced from said second terminal means of said load winding by an angle corresponding to the phase angle between the converters.
Claim 2
Dependent Claim
173 words
A load circuit for operation with a first and a second power converter wherein the output of the first converter has a phase angle relative to the output of the second converter, comprising in combination: a load winding having a phase winding for each phase of one of the converters and having inductively coupled auxiliary winding means on one common magnetic circuit; first terminal means of said load winding having terminals equal in number to the phases of the first converter; second terminal means of said load winding having terminals equal in number to the phases of the second converter; means connected between the first and second converters and said first and second terminal means, respectively, for absorbing voltage differences; and means for conductively connecting said phase and auxiliary winding means to each other and to said terminal means to have said first terminal means of said conductively connected load winding electrically displaced from said second terminal means of said load winding by an angle corresponding to the phase angle between the converters.
Claim 3
Dependent Claim
29 words
A load circuit as set forth in claim 1, wherein said means connected between the first and second converters and said first and second terminal means includes reactor means.
Claim 4
Dependent Claim
33 words
A load circuit as set forth in claim 1, wherein said means for connecting said phase and auxiliary winding means connects said phase windings to be symmetrically disposed with respect to one another.
Claim 5
Dependent Claim
24 words
A load winding as set forth in claim 1, wherein said auxiliary winding means includes at least one auxiliary winding for each phase winding.
Claim 6
Dependent Claim
61 words
A load winding as set forth in claim 4, wherein the first and second converters are polyphase converters; and said means for connecting said phase and auxiliary winding means connects said phase windings in series with said auxiliary windings with said auxiliary windings interposing said phase windings with one of said terminals at each connection of said phase and auxiliary windings.
Claim 7
Dependent Claim
68 words
A load winding as set forth in claim 4, wherein the first and second converters are polyphase converters; and said means for connecting said phase and auxiliary winding means interconnects said phase windings; and said means for connecting said phase and auxiliary winding means connects one of said auxiliary windings between each of said phase windings and a terminal of each of said first and second terminal means.
Claim 8
Dependent Claim
18 words
A load winding as set forth in claim 1, wherein the first and second power converters are inverters.
Claim 9
Dependent Claim
194 words
A load circuit for operation with a first and a second polyphase inverter wherein the first inverter output has a phase angle relative to the second inverter output, comprising in combination: a polyphase load winding on one common magnetic circuit and having a phase winding and at least one auxiliary winding for each phase of the first inverter; reactor means having first and second reactor coil means, a set of first polyphase terminals equal in number to the phases of the first inverter, a set of second polyphase terminals equal in number to the phases of the second inverter, means for connecting said first reactor coil means between the first inverter and said first terminals; means for connecting said second reactor coil means between the second inverter and said second terminals; and means for conductively connecting said phase and auxiliary windings to each other and to said terminals to have said phase windings symmetrically disposed with respect to each other with said first terminals of said polyphase conductively connected winding electrically displaced from said second terminals of said conductively connected polyphase load winding by an angle corresponding to the phase angle between the inverters.
Claim 10
Dependent Claim
194 words
A load circuit for operation with a first and a second polyphase inverter wherein the first inverter output has a phase angle relative to the second inverter output, comprising in combination: a polyphase load winding on one common magnetic circuit and having a phase winding and at least one auxiliary winding for each phase of the first inverter; reactor means having first and second reactor coil means, a set of first polyphase terminals equal in number to the phases of the first inverter, a set of second polyphase terminals equal in number to the phases of the second inverter, means for connecting said first reactor coil means between the first inverter and said first terminals; means for connecting said second reactor coil means between the second inverter and said second terminals; and means for conductively connecting said phase and auxiliary windings to each other and to said terminals to have said phase windings symmetrically disposed with respect to each other with said first terminals of said polyphase conductively connected winding electrically displaced from said second terminals of said conductively connected polyphase load winding by an angle corresponding to the phase angle between the inverters.
Claim 11
Dependent Claim
24 words
A load circuit as set forth in claim 8, wherein said reactor means includes a reactor core leg for each of said phase windings.
Claim 12
Dependent Claim
55 words
A load circuit as set forth in claim 8, wherein said means for connecting said phase and auxiliary windings to said terminals connects said phase windings in series with said auxiliary windings with said auxiliary windings interposing said phase windings with one of said polyphase terminals at each connection of said phase and auxiliary windings.
Claim 13
Dependent Claim
17 words
A load circuit as set forth in claim 10, wherein said polyphase winding is a ring winding.
Claim 14
Dependent Claim
62 words
A load circuit as set forth in claim 8, wherein said means for connecting said phase and auxiliary windings to said terminals interconnects one end of each of said phase windings and connects one of said auxiliary windings between the other end of each of said phase windings and a terminal of each of said first and second sets of polyphase terminals.
Claim 15
Dependent Claim
17 words
A load circuit as set forth in claim 12, wherein said polyphase winding is a forked winding.
Claim 16
Dependent Claim
30 words
A load circuit as set forth in claim 8, wherein the phase angle of the first inverter output relative to the second inverter output is an odd multiple of 30.degree..
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-07 | 1978-10-07 | 1979-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-07 | 1982-10-07 | 1983-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-07 | 1986-10-07 | 1987-04-08 | $7700.00 | Window Closed / Lapsed |