可实现辅助开关管准零电流开关的半无桥功率因数校正变换器

Semi Bridgeless Boost PFC Converter With Quasi-zero-current Switching Auxiliary Switch

提出一种可实现辅助开关管准零电流开关的零电压转换半无桥功率因数校正变换器拓扑。通过增加一个有源辅助谐振支路,变换器实现了主开关管的零电压开关和升压二极管的自然开关,并且没有增加它们的电压应力。与此同时,它还进一步减小了辅助开关管的开关损耗,而各连通二极管也均实现了自然开关。理论分析变换器的工作模态,详细讨论变换器软开关实现条件和控制策略,在此基础上给出有源辅助谐振支路参数设计。设计一台开关频率100kHz、额定输出400V/600W的原理样机,验证了变换器设计方案的可行性和理论分析的正确性。

An implementation of zero-voltage transition （ZVT） semi bridgeless boost power factor correction （PFC） converter with quasi-zero-current switching （ZCS） auxiliary switch was proposed. By using an active snubber circuit, the proposed converter provides zero-voltage switching （ZVS） for the main switches and switching naturally for the boost diodes without increasing the voltage stress of them. At the same time, it also further reduces the power loss of the auxiliary switch, and realizes switching naturally for the rest of the diodes. The operating modes of the converter were analyzed theoretically, the constraints under soft switching and control strategy design for the converter were discussed in detail. On the basis of it, the parameters of the active snubber were given. A prototype of proposed circuit operating at 100kHz switching frequency, 400V/600W rated output had been built to verify the feasibility of the design scheme and the correctness of theoretical analysis.