实现损耗均衡的新型相移控制策略的研究

针对全桥电路采用传统相移控制时,主桥臂上的损耗一直高于相移臂上损耗的问题,为了实现移相控制时主桥臂和相移臂上损耗的自动均衡分配,对相移臂和主桥臂的周期性功能切换做了研究,提出了一种基于数字信号处理器的新型数字移相控制的方法,使得在两个输出周期内全桥电路开关管在主桥臂和相移臂功能之间可以实现自动切换。为了验证新型移相控制方法的可行性,在搭建的150 k W全桥感应加热电源样机平台上对新型移相控制方法做了测试,并采用新型移相控制方法在满功率下对各个开关管的开通和关断电流情况做出了对比和分析。研究结果表明,该新型移相控制方法较好地解决了传统相移控制时电路存在的桥臂损耗不一致的问题,同时可以实现传统移相控制的所有功能。

New phase-shifted control with equal loss distribution

Aiming at the problems that disequilibrium of loss distribution of arms of full-bridge topology with phase-shifted control,research was made to fulfill equal loss distribution by function exchange between main arm and phase-shifted arm.A new digital phase-shifted control strategy based on digital signal processor was proposed,and test was made on a 150 kW inductive heating power source based on full bridge topology to testify the feasibility of the proposed control strategy by analyzing the current on IGBT when it turning-on or turning-off.The results indicate that the proposed control strategy can balance the power loss between two arms equally while achieving all the funtions traditional phase-shifted control has.