基于变压器前串后并的ZVS移相全桥变换器

A ZVS Phase-shifted Full-bridge Converter With Front Series and Back Parallel of Transformer

针对雷达阵面电源低压大电流输入的要求,提出基于变压器输入串联输出并联的移相全桥(PSFB)拓扑方案。对该拓扑部分关键开关模态进行分析,得出次级整流管在箝位二极管导通后仍然振荡的原因。为解决该问题,加入RCD吸收电路来抑制次级同步整流管电压振荡。最后,设计完成了一台4.5 kW零电压开关(ZVS)脉宽调制(PWM)PSFB变换器原理样机,其实验波形与理论分析相吻合,验证了方案的可行性。

Aiming at the requirements of low voltage and large current input for radar array power supply, a phaseshifted full-bridge(PSFB) topology scheme based on transformer input series output parallel is proposed. Partial key switching modes of the topology are analyzed to find out the reason why the secondary rectifier tube still oscillates after clamping diode conduction.To solve this problem, RCD absorption circuit is added to suppress voltage oscillation of secondary synchronous rectifier tube.Finally, a 4.5 kW zero voltage switch(ZVS) pulse width modulation(PWM)PSFB converter is designed and completed.The experimental waveform is consistent with the theoretical analysis, and the feasibility of the scheme is verified.