US3781634A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Integrated error voltage regulator for static switching circuits
Assignee: ELGAR ELECTRONICS Corp A CORP OF
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Filing: 1971-06-18
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Granted: 1973-12-25
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Expires: 1991-06-18
Abstract
Abstract The invention pertains to a technique for controlling the switching instants of static switching devices comprising power inverter and converter circuits. The unfiltered voltage output of the power conversion circuit is compared to a constant amplitude A.C. reference voltage waveform to obtain a signal indicative of the instantaneous deviation of the output of the power conversion system from the constant amplitude AC waveform. This signal is then integrated and applied through suitable drive circuit means to control the switching instants of the static switching devices comprising the power conversion system. The switching instant control established by the integrated signal functions to control the switching instants so as to minimize the deviation of the power conversion system output voltage from the constant AC reference voltage. The switching instant control provided by the integrated signal virtually eliminates low order harmonics present in the output voltage of the power conversion system.
Inventors
- 👤 R Jessee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:28
CPC Classifications
H; H02; H02M; H02M1/00; H02M1/08; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/505; H02M7/515; H02M7/525
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
183 words
In apparatus for converting input voltage from an input voltage source to a plurality of output voltage pulses in a pattern approximating a desired AC output voltage waveform, the combination of a power stage including a plurality of ON-OFF conduction controlled switching devices operatively coupled between said input voltage source and an electrical load, drive circuit means for actuating said ON-OFF conduction control switching devices to develop a pattern of output voltage pulses corresponding to an unfiltered output voltage waveform of said power stage, control circuit means for controlling the operation of said drive circuit means and including an AC reference voltage source, summing circuit means for developing an output signal proportional to the difference between said AC reference voltage and said unfiltered output voltage of said power stage, and integrator circuit mEans for integrating said output signal from said summing circuit means and developing an output signal to control said drive circuit means to reduce the fundamental frequency component of said difference to a relatively small constant value, thus maintaining a relatively constant AC output voltage substantially free of low order harmonics.
Claim 2
Dependent Claim
183 words
In apparatus for converting input voltage from an input voltage source to a plurality of output voltage pulses in a pattern approximating a desired AC output voltage waveform, the combination of a power stage including a plurality of ON-OFF conduction controlled switching devices operatively coupled between said input voltage source and an electrical load, drive circuit means for actuating said ON-OFF conduction control switching devices to develop a pattern of output voltage pulses corresponding to an unfiltered output voltage waveform of said power stage, control circuit means for controlling the operation of said drive circuit means and including an AC reference voltage source, summing circuit means for developing an output signal proportional to the difference between said AC reference voltage and said unfiltered output voltage of said power stage, and integrator circuit mEans for integrating said output signal from said summing circuit means and developing an output signal to control said drive circuit means to reduce the fundamental frequency component of said difference to a relatively small constant value, thus maintaining a relatively constant AC output voltage substantially free of low order harmonics.
Claim 3
Dependent Claim
63 words
An apparatus as claimed in claim 1 including an output filtering means for developing a filtered AC output voltage, and a fundamental frequency filter for developing an output signal proportional to the fundamental component of the voltage drop across said output filter, said signal being supplied to said summing circuit means to compensate for variation in voltage drop across said output filtering means.
Claim 4
Dependent Claim
44 words
In apparatus as claimed in claim 2 wherein said control circuit means include load transient responsive circuit means for monitoring said filtered AC output voltage and modifying said output signal from said means for integrating to compensate for transient variations in electrical load conditions.
Claim 5
Dependent Claim
21 words
An apparatus as claimed in claim 1 wherein said AC reference voltage source is a constant sine wave reference voltage source.
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) | 1976-12-24 | 1977-06-25 | 1977-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-24 | 1981-06-25 | 1981-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-24 | 1985-06-25 | 1985-12-25 | $7700.00 | Window Closed / Lapsed |