Alternated duty cycle control method for half-bridge DC-DC converter

A control method, namely, alternated duty cycle (ADC) control, is presented in this paper. This method can achieve soft-switching for at least one switch of the two half-bridge switches. When soft-switching can be only achieved for one switch, ADC control alternates the soft-switching realization between the two switches so that each switch will be soft-switched during half of the time and hard-switched during the other half, keeping equal power losses distribution between the switches. Moreover, any asymmetry in the duty cycle will not cause asymmetric components stresses or transformer DC bias when ADC control is used. Theoretical analysis and implementation are presented along with experimental results.