Study Of A High Power SMPS Based On PFC And Soft-switching Techniques

With the development of Power Electronics, the technology of Switching Mode Power Supply (SMPS) is gradually being perfect. However, there is no end to the demand for a high power, high performance power supply. Nowadays, Power Factor Correction (PFC) technique and soft-switching PWM technique are both widely researched. They have been prevalently applied in low power SMPS, and are still under research for applying in high power SMPS.A high power and high performance SMPS is designed in this paper to meet the demand of its consumer. It consists of forward stage and backward stage, of which the forward stage is a single-phase Boost Power Factor Correction circuit using IC UC3854. The backward stage main circuit is a Full-bridge converter using Phase-shifting Control Soft-switching technique.Based on the detailed analysis of the principle of single-phase active PFC, the high power active PFC circuit is designed, and the method of designing boost inductor is also given in the paper. A high power phase-shifted-control soft-switching full-bridge converter is designed, and the condition of achieving ZVS (Zero Voltage Switching) is studied in detail. Finally, the waves of a prototype are given.