Family of saturable reactor assisted soft-switching PWM DC—DC convertors

A family of improved soft-switching pulse width modulation DC—DC convertors employing a saturable reactor assisted soft-switching technique are presented. These convertors use a small saturable reactor(s) to achieve efficient soft switching, and have advantages such as low switching and low conduction losses, wide load range and constant frequency operation. A steady-state analysis is illustrated for a forward/flyback hybrid convertor belonging to the family, and key experimental results are shown and discussed. The voltage conversion ratios and voltage/current stresses for components in the family of convertors are summarised.