低电压电流应力的有源钳位ZVS软开关技术

Active Clamped ZVS Soft Switching Technology With Low Voltage and Current Stress

有源钳位零电压开关(zero-voltage switching,ZVS)软开关拓扑被广泛应用到DC/DC变换器实现开关管零电压开通。传统有源钳位软开关拓扑存在电压、电流应力大且占空比丢失严重的问题,制约了其在大功率DC/DC变换器中的应用。该文提出改进的有源钳位软开关拓扑,在传统拓扑基础上增加由二极管与辅助电感组成的电流转移电路,使二极管电流应力、钳位电压及占空比丢失均减小一半,提高变换器效率及可靠性。分析所提有源钳位软开关拓扑应用于Buck变换器及Boost变换器的工作原理,并对拓扑进行性能分析及参数设计。最后,在功率为1.2k W的Buck变换器及Boost变换器中,实验验证所提有源钳位软开关拓扑的正确性。

Active clamped zero-voltage switching(ZVS) soft switching topology is widely used in DC/DC converters to realize ZVS for the main switches. The traditional active clamped soft switching topology with the disadvantages of high voltage stress, high current stress and larger duty cycle loss will result in poor performances when used in high power DC/DC converters. A new active clamped soft switching topology was proposed in this paper. By adding a current transfer circuit composed of a diode and an auxiliary inductor to the traditional topology, the current stress, clamping voltage and duty cycle loss were all halved, which would result in high efficiency and reliability of the converter. The working principles of the proposed active clamped soft switching topology applied to Buck converter and Boost converter were analyzed and the performances analysis and parameters design of the topology were carried out. Finally, the experimental verification of the proposed active clamped soft switching topology was carried out based on a 1.2 kW Buck prototype converter and Boost prototype converter.