Electric power conversion systems – Current conversion – Including d.c.-a.c.-d.c. converter
Patent
1996-08-29
1999-10-26
Wong, Peter S.
Electric power conversion systems
Current conversion
Including d.c.-a.c.-d.c. converter
363 97, 363131, H02M 3335, H02M 324, H02M 7537
Patent
active
059739398
ABSTRACT:
A double forward DC-to-DC converter with soft-PWM switching provides two voltage pulses to the output low-pass filter within one switching cycle (hence, the name double forward). The double forward DC to DC converter includes a transformer having a single primary winding and a two secondary windings. A main switch, under the control of a PWM control circuit, is connected is series with the primary winding. An auxiliary switch is coupled across with the main switch by way of a resonant capacitor. The resonant capacitor and auxiliary switch are used to automatically reset the transformer core while the main switch is on back to the voltage source connected to the transformer primary. A diode and snubber capacitor is connected across the drain-source terminals for both the main and auxiliary switches for minimizing switching losses. The current mirror used in prior art is abandoned in order to avoid the locked-up mode of operation.
The secondary windings of the transformer are connected to a pair of saturable reactors which, in turn, are connected to rectifier diodes in order to eliminate the reverse recovery losses of the rectifier diodes. A freewheeling diode is connected across the secondary winding and cooperates with the saturable reactors to maintain the load current to the secondary windings during the transitions of the main and auxiliary switches.
REFERENCES:
patent: 4441146 (1984-04-01), Vinciarelli
patent: 4809148 (1989-02-01), Barn
patent: 4959764 (1990-09-01), Bassett
patent: 5066900 (1991-11-01), Bassett
patent: 5126931 (1992-06-01), Jitaru
patent: 5231563 (1993-07-01), Jitaru
patent: 5325283 (1994-06-01), Farrigton et al.
patent: 5363289 (1994-11-01), Jacobs
patent: 5434768 (1995-07-01), Jitaru et al.
J.A. Bassett, Constant Frequency ZVS Converter with Integrated Magnetics, publication No. 0-7803-0485-3/92, IEEE 1992, pp. 709-716.
Bruce Carsten, Design Techniques for Transformer Active Reset Circuits at High Frequencies and Power Levels, HFPC-May 1990 Proceedings, pp. 235-245.
Koosuke Harada and Hiroshi Sakamoto, Switched Snubber for High Frequency Switching, publication No. CH2873-8/90/0000-0181 1990 IEEE, pp. 181-188.
Ionel Dan Jitaru, High Frequency, Soft Transitions Converter, publication No. 0-7803-0982-0/93, 1993 IEEE, pp. 880-887.
Patel Rajnikant B.
TRW Inc.
Wong Peter S.
Yatsko Michael S.
LandOfFree
Double forward converter with soft-PWM switching does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Double forward converter with soft-PWM switching, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Double forward converter with soft-PWM switching will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-771489