Research Of Full Bridge Phase-shifted Zvzcs Converter Based On Digital Control

High frequency, modular construction and digitalization is the main development tendency in the field of the switching power supply. High power density and high frequency converter is based on soft-switching techniques. Full Bridge Phase-Shifted zero-voltage and zero-current-switching (ZVZCS) converter is a succesful implementation for soft-switching and is easy for usage in DC-DC converter. In order to reach both high frequency and digitalization of converter, a novel ZVZCS converter is proposed using a coupled output inductor based on digital control in this paper.The principle of the novel converter is analyzed, and the foundations of parameter-design are presented. Furthermore, parameter calculation formulas at different modes are deduced. A digital control system based on Sunplus Singlechip SPCE061A controller is designed and achieves the output of Phase-shifting PWM signal. A simulation is performed for the converter using PSpice9.2, and different parameters' effects on performance of converter are analyzed. A ZVZCS soft-switching power supply with 48V/480W based on this topology and digital control strategy is developed. Also the design of main, control, drives and protection circuits are presented. Lastly, working waveforms of the converter are measured on the prototype.Theory analysis and experiments have showed that this novel converter can realize ZVS of leading-legs at the condition of more than one-three full load and ZCS of legging-legs in the whole range of load, it has many advantages such as simple auxiliary circuit, low voltage stress of rectifier diode, self-adjustment of circulating current and high efficiency; The control system's hardware structure is simple, highly integrated and this converter achieves the aim of digital control and error protect; the correctness and reliability of the whole design is validated.