US3715648A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Technique for use of controlled current feedback transformers in power inverter apparatus
Assignee: Westinghouse Electric Corp
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Filing: 1972-02-01
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Granted: 1973-02-06
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Expires: 1992-02-01
Abstract
Abstract A technique for improving the interlock operation of a power inverter apparatus including a power stage operatively coupled to a steering stage by a controlled current feedback transformer (CCFT). Each of the stages includes a pair of switching devices and the alternate conduction of the switching devices controls the conductive state of the switching devices of the power stage. An interlock circuit operatively coupled between the power stage and steering stage controls the conductive states of the switching devices of the steering stage in response to current flow in the switching devices of the power stage. A residual bias circuit is operatively connected to the steering stage to maintain the switching devices in a conductive state for a period of time to assure effective interlock circuit operation. A nonlinear energy absorbing device, such as a transformer is positioned intermediate to said CCFT and said interlock circuit to absorb erroneous currents produced by stored energy in the core of the CCFT.
Inventors
- 👤 A Kernick
- 👤 M Geyer
- 👤 G Ernsberger
- 👤 J Vonderembse
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:12
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/53; H02M7/537; H02M7/538; H02M7/5381
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
246 words
In a power inverter apparatus having a power stage including a pair of ON-OFF power switching devices operatively connected for alternately supplying the output of said power inverter apparatus, a steering circuit including a pair of ON-OFF steering switching devices, transFormer means operatively coupling said power stage and said steering stage the conductive state of said steering switching devices controlling the conductive state of said power switching devices, interlock circuit means operatively connected to said steering stage for controlling the conduction of said steering switching devices in response to the conductive condition of said power switching devices and drive circuit means for generating alternate actuation output signals for alternately changing the conductive state of said steering switching devices, an OFF conductive state of one of said steering switching devices resulting in an ON conductive state of the associated power switching device, the improvement for establishing a simultaneous ON conductive state of said pair of steering switching devices for a time adequate to permit operation of said interlock circuit, said improvement comprising a residual biasing means operatively associated with said pair of steering switching devices and responding to the alternate actuation output signals of said drive circuit means by maintaining the OFF going one of said pair of steering switching devices in an ON conductive state for a period of time sufficient to establish simultaneous conduction of said pair of steering switching devices for a brief period of time sufficient to permit operation of said interlock circuit.
Claim 2
Dependent Claim
246 words
In a power inverter apparatus having a power stage including a pair of ON-OFF power switching devices operatively connected for alternately supplying the output of said power inverter apparatus, a steering circuit including a pair of ON-OFF steering switching devices, transFormer means operatively coupling said power stage and said steering stage the conductive state of said steering switching devices controlling the conductive state of said power switching devices, interlock circuit means operatively connected to said steering stage for controlling the conduction of said steering switching devices in response to the conductive condition of said power switching devices and drive circuit means for generating alternate actuation output signals for alternately changing the conductive state of said steering switching devices, an OFF conductive state of one of said steering switching devices resulting in an ON conductive state of the associated power switching device, the improvement for establishing a simultaneous ON conductive state of said pair of steering switching devices for a time adequate to permit operation of said interlock circuit, said improvement comprising a residual biasing means operatively associated with said pair of steering switching devices and responding to the alternate actuation output signals of said drive circuit means by maintaining the OFF going one of said pair of steering switching devices in an ON conductive state for a period of time sufficient to establish simultaneous conduction of said pair of steering switching devices for a brief period of time sufficient to permit operation of said interlock circuit.
Claim 3
Dependent Claim
246 words
In a power inverter apparatus having a power stage including a pair of ON-OFF power switching devices operatively connected for alternately supplying the output of said power inverter apparatus, a steering circuit including a pair of ON-OFF steering switching devices, transFormer means operatively coupling said power stage and said steering stage the conductive state of said steering switching devices controlling the conductive state of said power switching devices, interlock circuit means operatively connected to said steering stage for controlling the conduction of said steering switching devices in response to the conductive condition of said power switching devices and drive circuit means for generating alternate actuation output signals for alternately changing the conductive state of said steering switching devices, an OFF conductive state of one of said steering switching devices resulting in an ON conductive state of the associated power switching device, the improvement for establishing a simultaneous ON conductive state of said pair of steering switching devices for a time adequate to permit operation of said interlock circuit, said improvement comprising a residual biasing means operatively associated with said pair of steering switching devices and responding to the alternate actuation output signals of said drive circuit means by maintaining the OFF going one of said pair of steering switching devices in an ON conductive state for a period of time sufficient to establish simultaneous conduction of said pair of steering switching devices for a brief period of time sufficient to permit operation of said interlock circuit.
Claim 4
Dependent Claim
246 words
In a power inverter apparatus having a power stage including a pair of ON-OFF power switching devices operatively connected for alternately supplying the output of said power inverter apparatus, a steering circuit including a pair of ON-OFF steering switching devices, transFormer means operatively coupling said power stage and said steering stage the conductive state of said steering switching devices controlling the conductive state of said power switching devices, interlock circuit means operatively connected to said steering stage for controlling the conduction of said steering switching devices in response to the conductive condition of said power switching devices and drive circuit means for generating alternate actuation output signals for alternately changing the conductive state of said steering switching devices, an OFF conductive state of one of said steering switching devices resulting in an ON conductive state of the associated power switching device, the improvement for establishing a simultaneous ON conductive state of said pair of steering switching devices for a time adequate to permit operation of said interlock circuit, said improvement comprising a residual biasing means operatively associated with said pair of steering switching devices and responding to the alternate actuation output signals of said drive circuit means by maintaining the OFF going one of said pair of steering switching devices in an ON conductive state for a period of time sufficient to establish simultaneous conduction of said pair of steering switching devices for a brief period of time sufficient to permit operation of said interlock circuit.
Claim 5
Dependent Claim
173 words
In a power inverter apparatus as claimed in claim 1 wherein said residual bias circuit means includes a transistor flip-flop circuit having a first stage including a first transistor operatively connected between said drive circuit means and one of said steering switching devices and a second stage including a second transistor operatively connected between said drive circuit means and the other of said steering switching devices, each of said stages including a resistor-blocking rectifier combination, said first and second stage responding to said alternate actuation output signals of said drive circuit means by alternately rendering said steering switching devices ON and OFF, the resistor-blocking rectifier combination of the respective flip-flop stages functioning to maintain the steering switching device associated with the respective flip-flop stages in an on conductive state following termination of the drive circuit actuation signal for a period of time sufficient to render the other of said steering switching device conductive in response to said drive circuit activating signal thereby said establishing simultaneous conduction of said pair of steering switching devices.
Claim 6
Dependent Claim
102 words
In a power inverter apparatus as claimed in claim 1 wherein said interlock circuit is operatively connected between said transformer means and said steering stage to delay the turn-off of the respective steering switching devices until the current flow in the power switching device changing from an ON conductor state to an OFF conductive approximates a predetermined value, and a non-linear energy absorbing means intermediate said transformer means and said interlock circuit to absorb residual output currents developed by said transformer means following essential termination of the current flow in said power switching device thus preventing erroneous operation of said interlock circuit.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-06 | 1976-08-07 | 1977-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-06 | 1980-08-07 | 1981-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-06 | 1984-08-07 | 1985-02-06 | $7700.00 | Window Closed / Lapsed |