Investigation of zero-current switching fixed frequency resonant-transition square wave converters

Most of the soft-switching power converters, especially zero-current switching resonant converters, are required to vary switching frequency to control their output voltage. A family of newly designed zero-current switching fixed frequency square wave resonant converters is proposed. The output voltage of these converters can be controlled by the on-state period of a semiconductor switch; and therefore, they can be operated at a fixed switching frequency. All of the switching devices are in the zero-current switching condition. Also, the peak current of each switching device is minimized. Computer simulation and experimental results are presented to support the operation of the converters.