US5418704A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Zero-voltage-transition pulse-width-modulated converters
Assignee: Virginia Tech Intellectual Properties Inc
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Filing: 1993-05-24
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Granted: 1995-05-23
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Expires: 2013-05-24
Abstract
Abstract To date, soft-switching techniques applied to the PWM converters, with the exception of a few isolated cases, are subjected to either high switch voltage stresses or high switch current stresses, or both. This invention presents a new class of zero-voltage-transition PWM converters, where both the transistor and the rectifier operate with zero-voltage switching, and are subjected to minimum voltage and current stresses. Breadboarded converters are constructed to verify the novelty of the proposed new family of converters.
Inventors
- 👤 Guichao C. Hua
- 👤 Fred C. Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:31
CPC Classifications
H; H02; H02M; H02M3/00; H02M3/02; H02M3/04; H02M3/10; H02M3/145; H02M3/155; H02M3/156; H02M3/158; Y; Y02; Y02B; Y02B70/00; Y02B70/10
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
229 words
A pulse-width-modulated d.c. to d.c. converter comprising in combination: a d.c. voltage input means; a d.c. voltage output means including an output filter and a rectifier diode; a pulse-width-modulating switch connected between said d.c. voltage input means and said d.c. voltage output means; a resonant circuit comprised of a capacitance, an inductance, and an auxiliary switch; means connecting said resonant circuit in parallel with pulse-width-modulating switch; a pulse-width-modulating signal source with means connecting said signal source to said pulse-width-modulating switch, and means connecting said signal source to said auxiliary switch; said pulse-width-modulating signal source switching said pulse-width-modulating switch between an on state and an off state at a fixed frequency and a varying duty cycle; said auxiliary switch being switched to an on state prior to said pulse-width-modulating switch being switched to an on state so that said auxiliary switch is in said on state a sufficient interval that said resonant circuit establishes a substantially zero voltage across said pulse-width-modulating switch when said pulse-width-modulating switch switches to an on state and said auxiliary switch being switched back to an off state for an interval after said pulse-width-modulating switch switches to an on state in order to control the resonance of said resonant circuit, whereby the pulse-width-modulating switch operates at a constant frequency with zero voltage switching of said pulse width-modulating switch and said rectifier diode over wide load range.
Claim 2
Dependent Claim
229 words
A pulse-width-modulated d.c. to d.c. converter comprising in combination: a d.c. voltage input means; a d.c. voltage output means including an output filter and a rectifier diode; a pulse-width-modulating switch connected between said d.c. voltage input means and said d.c. voltage output means; a resonant circuit comprised of a capacitance, an inductance, and an auxiliary switch; means connecting said resonant circuit in parallel with pulse-width-modulating switch; a pulse-width-modulating signal source with means connecting said signal source to said pulse-width-modulating switch, and means connecting said signal source to said auxiliary switch; said pulse-width-modulating signal source switching said pulse-width-modulating switch between an on state and an off state at a fixed frequency and a varying duty cycle; said auxiliary switch being switched to an on state prior to said pulse-width-modulating switch being switched to an on state so that said auxiliary switch is in said on state a sufficient interval that said resonant circuit establishes a substantially zero voltage across said pulse-width-modulating switch when said pulse-width-modulating switch switches to an on state and said auxiliary switch being switched back to an off state for an interval after said pulse-width-modulating switch switches to an on state in order to control the resonance of said resonant circuit, whereby the pulse-width-modulating switch operates at a constant frequency with zero voltage switching of said pulse width-modulating switch and said rectifier diode over wide load range.
Claim 3
Dependent Claim
244 words
A pulse-width-modulated d.c. to d.c. converter comprising in combination: a d.c. voltage input means; a d.c. voltage output means including an output filter and a rectifier diode; a pulse-width-modulating switch connected between said d.c. voltage input means and said d.c. voltage output means; a resonant circuit comprised of a capacitance, an inductance, and an auxiliary switch; means connecting said resonant circuit in parallel with pulse-width-modulating switch and means connecting a node of said resonant circuit to a terminal of said rectifier diode; a pulse-width-modulating signal source with means connecting said signal source to said pulse-width-modulating switch, and means connecting said signal source to said auxiliary switch; said pulse-width-modulating signal source switching said pulse-width-modulating switch between an on state and an off state at a fixed frequency and a varying duty cycle; said auxiliary switch being switched to an on state prior to said pulse-width-modulating switch being switched to an on state so that said auxiliary switch is in said on state a sufficient interval that said resonant circuit establishes a substantially zero voltage across said pulse-width-modulating switch when said pulse-width-modulating switch switches to an on state and said auxiliary switch being switched back to an off state for an interval after said pulse-width-modulating switch switches to an on state in order to control the resonance of said resonant circuit, whereby the pulse-width-modulating switch operates at a constant frequency with zero voltage switching of said pulse-width-modulating switch and said rectifier diode over wide load range.
Claim 4
Dependent Claim
244 words
A pulse-width-modulated d.c. to d.c. converter comprising in combination: a d.c. voltage input means; a d.c. voltage output means including an output filter and a rectifier diode; a pulse-width-modulating switch connected between said d.c. voltage input means and said d.c. voltage output means; a resonant circuit comprised of a capacitance, an inductance, and an auxiliary switch; means connecting said resonant circuit in parallel with pulse-width-modulating switch and means connecting a node of said resonant circuit to a terminal of said rectifier diode; a pulse-width-modulating signal source with means connecting said signal source to said pulse-width-modulating switch, and means connecting said signal source to said auxiliary switch; said pulse-width-modulating signal source switching said pulse-width-modulating switch between an on state and an off state at a fixed frequency and a varying duty cycle; said auxiliary switch being switched to an on state prior to said pulse-width-modulating switch being switched to an on state so that said auxiliary switch is in said on state a sufficient interval that said resonant circuit establishes a substantially zero voltage across said pulse-width-modulating switch when said pulse-width-modulating switch switches to an on state and said auxiliary switch being switched back to an off state for an interval after said pulse-width-modulating switch switches to an on state in order to control the resonance of said resonant circuit, whereby the pulse-width-modulating switch operates at a constant frequency with zero voltage switching of said pulse-width-modulating switch and said rectifier diode over wide load range.
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) | 1998-05-22 | 1998-11-21 | 1999-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-05-22 | 2002-11-21 | 2003-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-05-22 | 2006-11-21 | 2007-05-23 | $7700.00 | Window Closed / Lapsed |