Patent US4591963A successfully refreshed from Google Patents.
US4591963A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Technique for reducing line current harmonics at input to power supply acting as nonlinear load
Assignee: Nokia Bell Labs
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Filing: 1984-04-23
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Granted: 1986-05-27
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Expires: 2004-04-23
Abstract
Abstract Harmonic currents of the line frequency on the input line of a power converter are significantly reduced by actively controlling the input current to have substantially the same waveform and be in phase with the input AC sinusoidal voltage. Specific peak current control techniques are utilized to constrain current in an input inductor to be in phase with and approximate in waveform the input voltage sinusoidal waveform by operating a switch at a much higher frequency than that of the input AC voltage source; with the peak current control using the input AC voltage as a controlling reference voltage waveform.
Inventors
- 👤 Daniel D. Retotar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:12
CPC Classifications
H; H02; H02M; H02M1/00; H02M1/42; H02M1/4208; H02M1/4258; H02M1/12; Y; Y02; Y02B; Y02B70/00; Y02B70/10
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
185 words
A converter adapted for minimizing line frequency harmonic currents generated at a source of energy for a system comprising: input means, output means, power switching apparatus interposed between the input means and the output means and including a plurality of switching devices connected in a bridge network, inductive means for providing energy storage operating in a continuous current mode and coupled to supply current from the input means to the power switching apparatus, means for generating a reference waveform in phase with and of similar wave shape to an energizing waveform at the input means, means for generating an error voltage representative of a deviation of a voltage at the output means from a regulated value, means for adjusting an amplitude of the reference waveform in response to the error voltage, and means for driving the power switching apparatus in response to the means for adjusting and operative for controlling a current waveform in the inductive means to substantially equal the shape of the reference waveform and, further, being operative to bias all switching devices conductive simultaneously to initiate current flow in the inductive means.
Claim 2
Dependent Claim
185 words
A converter adapted for minimizing line frequency harmonic currents generated at a source of energy for a system comprising: input means, output means, power switching apparatus interposed between the input means and the output means and including a plurality of switching devices connected in a bridge network, inductive means for providing energy storage operating in a continuous current mode and coupled to supply current from the input means to the power switching apparatus, means for generating a reference waveform in phase with and of similar wave shape to an energizing waveform at the input means, means for generating an error voltage representative of a deviation of a voltage at the output means from a regulated value, means for adjusting an amplitude of the reference waveform in response to the error voltage, and means for driving the power switching apparatus in response to the means for adjusting and operative for controlling a current waveform in the inductive means to substantially equal the shape of the reference waveform and, further, being operative to bias all switching devices conductive simultaneously to initiate current flow in the inductive means.
Claim 3
Dependent Claim
40 words
A converter as defined in claim 1 wherein the means for adjusting comprises: a transconductance amplifier having an input from the means for generating a reference waveform and having its gain controlled by the means for generating an error voltage.
Claim 4
Dependent Claim
40 words
A converter as defined in claim 2 wherein the means for driving includes: means for sensing a current in the inductive means, and means for comparing an output of the means for sensing with an output of the transconductance amplifier.
Claim 5
Dependent Claim
24 words
A converter as defined in claim 3 wherein the means for sensing includes: means for comparing a sensed current with a generated error signal.
Claim 6
Dependent Claim
174 words
A converter having a control means for reducing harmonic distortion at an input comprising: means for rectifying an AC signal connected to the input means, means for pulse width modulating a current signal including power switching devices, inductive means coupling an output of the means for rectifying to the means for pulse width modulating, means for sensing a current level in the inductive means including a current transformer having a current sensing winding in series with a winding of the inductive means, means for generating a reference waveform having a waveshape substantially similar to the AC signal and being in phase therewith, means for sensing an output voltage of the converter and generating an error signal responsive to its deviations from a desired regulated value, means for adjusting an amplitude of the reference waveform in response to the error signal, means for comparing an amplitude of the current level with an amplitude of the reference waveform, and drive means for controlling the means for pulse width modulating in response to the means for comparing.
Claim 7
Dependent Claim
174 words
A converter having a control means for reducing harmonic distortion at an input comprising: means for rectifying an AC signal connected to the input means, means for pulse width modulating a current signal including power switching devices, inductive means coupling an output of the means for rectifying to the means for pulse width modulating, means for sensing a current level in the inductive means including a current transformer having a current sensing winding in series with a winding of the inductive means, means for generating a reference waveform having a waveshape substantially similar to the AC signal and being in phase therewith, means for sensing an output voltage of the converter and generating an error signal responsive to its deviations from a desired regulated value, means for adjusting an amplitude of the reference waveform in response to the error signal, means for comparing an amplitude of the current level with an amplitude of the reference waveform, and drive means for controlling the means for pulse width modulating in response to the means for comparing.
Claim 8
Dependent Claim
31 words
A converter as defined in claim 5 wherein the means for pulse width modulating includes a bridge inverter and the power switching devices comprise first, second, third and fourth power transistors.
Claim 9
Dependent Claim
30 words
A converter as defined in claim 5 wherein the means for generating a reference waveform includes first and second amplifiers for amplifying and rectifying adjacent half-cycles of the AC signal.
Claim 10
Dependent Claim
48 words
A converter as defined in claim 5 wherein the means for adjusting includes a transconductance amplifier responsive to the error signal, and the means for sensing a current level includes a ramp generator and means for superimposing a ramp output of the ramp generator upon the current level.
References Cited (Backward Citations)
US3913002A
Cited
US4193111A
Cited
US4293905A
Cited
US4340931A
Cited
US4489371A
Cited
US4472672A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-05-26 | 1989-11-25 | 1990-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-05-26 | 1993-11-25 | 1994-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-05-26 | 1997-11-25 | 1998-05-27 | $7700.00 | Window Closed / Lapsed |