Asymmetrical PWM half-bridge convertor with independently regulated multiple outputs

An asymmetrical PWM half-bridge convertor with independently regulated multiple outputs is proposed. Each output is regulated by its own feedback control circuit and a duty ratio of the primary switch is determined mainly by the input voltage of the convertor. Thus cross regulation between outputs is almost eliminated. In addition, the proposed convertor can achieve zero-voltage switching (ZVS) by complementary control. The operation of the proposed convertor is analysed and the concepts of the proposed convertor were verified by experimental results obtained from a 24 V/6 A, 12 V/4 A prototype.