磁耦合谐振式无线电能传输系统频率复合控制方法

Frequency compound control method of MCR-WPT system

频率的稳定及精确控制是磁耦合谐振式无线电能传输系统高效稳定运行的基础。提出一种基于PI锁相环频率跟踪控制和动态补偿调谐相结合的频率复合控制方法,实现了常规频率控制方法无法同时实现的大范围、高精度和快速频率调节。首先,根据建立的磁耦合谐振式无线电能传输系统数学模型,从原理上分析发生频率失谐的原因,给出了合理的频率失谐检测方法,并分析了系统等效阻抗角与谐振频率之间的对应关系;建立频率跟踪控制与动态补偿调谐的数学模型,以计算并确定锁相环PI参数及动态补偿参数;随后进行仿真并搭建试验平台验证,仿真结果表明该方法对谐振频率的调节速度快、精度高,试验结果验证该方法可以实现谐振频率的快速跟踪,保证系统工作在谐振状态。

Stability and precise control of frequency of the magnetically-coupled resonant wireless power transfer system(MCR-WPT)is the basis for its efficient and stable operation.A frequency compound control method is proposed based on phase-locked loop frequency tracking control combined with dynamic resonant compensation approach.The method can realize the large frequency adjustment range,high adjustment accuracy and fast adjustment speed that conventional frequency control methods cannot achieve at the same time.Firstly,the mathematical model of MCR-WPT was established and the mechanism of system detuning was analyzed theoretically.A frequency detuning detection method was proposed,and the corresponding relationship between the equivalent impedance angle and the resonant frequency was analyzed.According to the advantages of the two frequency modulation methods,the control strategies between frequency tracking control and dynamic resonant compensation approach were designed.The mathematical models of frequency tracking control and dynamic resonant compensation approach were established respectively to calculate and determine the PI parameters of the phase locked loop(PLL)and dynamic compensation parameters.Simulation and test platform were built.The simulation results show that this method has high accuracy and velocity in adjusting resonance frequency.Finally,the experimental results show that this method can achieve fast tracking of resonant frequency and keep the system working in resonant state.