新型LLC谐振负载感应加热电源移相控制研究

Study of phase-shifted control for a novel induction heating power supply with LLC resonant load

为了提高电源效率,使电源输出额定功率,采用静电耦合的方法设计LLC谐振负载实现负载匹配,分析了LLC谐振负载的特性和负载匹配实现的原理以及感应加热电源控制变量的选取。另外,在LLC谐振负载的基础上,针对感应加热电源移相调功时,具有较大的开关损耗问题,提出了一种新型LLC谐振负载感应加热电源拓扑结构,该结构下逆变器开关器件基本上都能够实现软开关,给出了移相调功的工作原理和输出功率的分析计算,并通过仿真,验证了理论分析的合理性。

In order to improve the efficiency of power supply and make it export rated power,the method of electrostatic coupling was applied to design LLC resonant load for implementing load matching.In this paper,the characteristics of LLC resonant load,the principle of load matching and the selection of control variables for induction heating power supply were analyzed.Moreover,on the basis of LLC resonant load,it had larger switching losses for the induction heating power supply under phase-shifted control,therefore,a novel induction heating power supply topology with LLC resonant load was presented,in which almost all of the inverter switches could achieve soft-switching.The principle of phase-shifted control and the calculation of output power were provided,besides,the theoretical analysis was verified by the simulation results.