一种基于FPGA的LCL型感应IPT系统的频率跟踪方法

A frequency tracking method of LCL type Inductive Power Transfer system based on FPGA

通过建立系统的互感耦合模型,对串并联(LCL)型感应电能传输系统的频率特性进行分析,结果表明,系统的软开关频率会因负载的变化而改变。针对这种特性,基于FPGA设计了一种闭环频率跟踪方法,经实验验证,当负载在较宽范围内发生变化时,该方法可使系统原边逆变器的工作频率跟踪系统的软开关频率,确保了逆变器开关管工作在零电流开关(ZCS)切换模式。

The frequency characteristics of the inductor-capacitor-inductor（LCL） type Inductive PowerTransfer（IPT） system are analyzed by establishing the system mutual inductance coupling model. As aresult of the analysis, the soft switching frequency is varied with the load. Therefore, a closed loopfrequency tracking method based on FPGA is designed. It is verified by experiments that this method canmake the operation frequency of the primary converter track the soft frequency and ensures the switcheswork at Zero Current Switch（ZCS） mode.