Title :
A zero-current-switching PWM flyback converter with a simple auxiliary switch
Author :
Chung, Henry Shu-Hung ; Hui, S.Y. ; Wang, Wei-Hua
Author_Institution :
Dept. of Electron. Eng., City Univ. of Hong Kong, Hong Kong
fDate :
3/1/1999 12:00:00 AM
Abstract :
A simple and effective approach of turning an isolated hard-switched converter design into a soft-switched one is presented. By adding an auxiliary winding, switch and small capacitor to the conventional pulsewidth modulation (PWM) isolated flyback converter, all switches and diodes are softly turned on and off. No extra active or passive voltage clamp circuit is needed to suppress voltage stress on the switching devices that were usually found in classical converters. A zero-current-switching (ZCS) PWM flyback converter topology with multiple outputs is analyzed and examined. The proposal inherently utilizes the leakage inductance of the “flyback” transformer to achieve ZCS of all switching devices. A complete steady-state DC analysis and the operating principle are described. The performance of an 80 W experimental converter prototype with dual-voltage outputs is included
Keywords :
DC-DC power convertors; PWM power convertors; power semiconductor switches; power transformers; switching circuits; transformer windings; 80 W; PWM flyback power converter; PWM isolated flyback converter; ZCS; auxiliary winding; flyback transformer; leakage inductance; multiple outputs; operating principle; performance; simple auxiliary switch; soft-switching; steady-state DC analysis; switching devices; zero-current-switching; Capacitors; Circuits; Clamps; Diodes; Pulse width modulation; Pulse width modulation converters; Switches; Switching converters; Turning; Zero current switching;
Journal_Title :
Power Electronics, IEEE Transactions on
