The Development Of Zero-Voltage-Switching Three-level DC/DC Converter

Three-level converter is a novel technology that is produced and developed in 1980's. Three-level ladder output voltage is accomplished by DC-side division voltage and different switch combination, and the capacity of converter system and endure voltage are efficiently improved, and the output voltage harmonics and switch loss are reduced. Zero-voltage-switching three-level DC/DC converter in the thesis is developed and manufactured, and the basic operation principle and its control strategies of three-level zero-soft-switch PWM DC converter are discussed. Hardware design of main system and control system is accomplished by circuit design software PROTEL99SE. The difference of leading switches and lagging switches to realize the zero-voltage switching and the reason of duty-cycle loss is emphatically argued. The realization of shift-phase PWM control with zero-voltage and high speed, large power drive circuit is emphatically solved.Finally, the operation principle of three-level shift phase PWM control with zero voltage is validated by the simulation analyze and the debugging experiment of 230V/10A sample device. Wei Xiaoguang(Power Electronics and Electrical Driver)Directed by prof. Shi Xinchun...