摘要
对一种采用占空比移相PWM控制方式的改进型半桥DC/DC变换器进行了研究。针对对称半桥在占空比很小时无法实现软开关和不对称半桥变压器必然存在直流磁化电流以及器件电压应力不同等问题,该控制方法引入一个附加的二极管和开关管,消除了因为漏感和寄生电容谐振引起的损耗,并实现了开关管的ZVS。在同样条件下将该控制方法与对称半桥进行了对比。实验结果证明,使用该方法可以实现变换器的高频运行,并且在宽范围的输入电压下保持较高的效率。
An improved Half-Bridge （HB） topology with Duty Cycled Shifted Pulse Width Modulation（DCS-PWM ） control method is studied in this paper.As it is known,traditional symmetrical and asymmetrical control has several drawbacks.In symmetrical control,ZVS is hard to realize,while in asymmetrical control there exists uneven stresses in corresponding components and DC magnetizing current.The improved DCS method is a better solution.By introducing a diode and an additional switch,it reduces the leakage-inductance-related power losses and high efficiency at high frequency with wide input voltage range may be achieved.600W/12V experiments with both symmetrical control and DCS control are carried out,which proves that the improved DCS HB has more advantages.
出处
《电力电子技术》
CSCD
北大核心
2006年第3期94-95,共2页
Power Electronics
