Patent ID: 6201714
Filing Date: 2001-03-13
Classification: H02M

Abstract:
An exchanging converter comprising:an input voltage filter capacitor bridging two opposite ends of an input power source to provide a stable input voltage;a transformer for storing and releasing electric energy, said transformer comprising a primary winding and a secondary winding;a primary power switch forming with said primary winding a series loop that bridges two opposite ends of said input voltage filter capacitor;an output voltage filter capacitor;a secondary power switch forming with said secondary winding a series loop that bridges two opposite ends of said output voltage filter capacitor for enabling said output voltage filter capacitor to smooth a high frequency switching waveform from said primary and secondary power switches, and to provide a stable DC output voltage to a load that also bridges said two opposite terminals of the output voltage filter capacitor; anda zero-voltage switching control circuit for driving said output voltage filter capacitor to partially feed back storage energy to an input side of said transformer, and for respectively providing a complementary driving signal to said primary power switch and said secondary power switch to control a turn-off time of said primary power switch and said secondary power switch when said primary power switch and said secondary power switch reach a zero-voltage switching control condition, so as to drive said primary power switch and said secondary power switch to repeat the switching operation at zero-voltage again and again.