一种改进型ZVZCS移相全桥线路

摘要

Aiming at the existing problems of phase-shift full bridge circuit,an improved circuit was proposed by adding a group of bridge arm(CLC)based on the traditional phase-shift full bridge circuit.The bridge arm is connected to the lagging arm to provide the switching current for the lagging arm.Therefore,it is more easy to achieve zero voltage switching for lagging arm.In addition,the bridge arm also provides current to output rectifier diode by a transformer to achieve the zero current switching.The circuit working process and the waveforms of key components were provided in detail and the key parameters of components in the circuit were given.Finally,the prototype of 1 200 W was demonstrated for a communication power supply with output voltage range of 40 V～60 V and the maximum output current of 20 A.Results show that the withstand voltage of the diode and electromagnetic interference is reduced rapidly,the proposed circuit can achieve the desired demand and high efficiency of 96.3％.%针对移相全桥线路中存在的不足,提出了一种改进线路:增加一组桥臂(CLC).该桥臂与滞后桥臂相连,并提供了滞后桥臂开关管的开关动作电流,使其较为容易地实现零电压开通;另外,该桥臂还为输出整流二极管提供电流,以实现其零电流关断,从而,降低了二极管的耐压等级,并减小了电磁干扰.对给出的线路,进行了详尽的工作过程分析,并给出了关键器件的波形及出关键器件的参数设计.最后,设计了一款功率为1 200W的通信电源样机,输出电压范围为40 V～60 V,最大输出电流为20 A.研究结果证明,该线路达到了预期效果,并取得了较高效率,最高效率达96.3％.