Research On Frequency Tracking Control Of Wireless Power Transfer Via Magnetic Resonance Coupling

Wireless Power Transfer(WPT)is a new technology that utilizes space wireless soft media to realize power transmission,which is safe and convenient.In recent years,WPT has attracted much attention.Magnetically Coupled Resonant Wireless Power Transfer(MCRWPT)is a kind of WPT technology,with high transmission efficiency,transmission distance of the advantages.In order to solve the problem of detuning caused by the resonant frequency offset of MCRWPT system,this paper studies the frequency tracking control method of MCRWPT system.This method has a wide range of applications,can be used for fixed-point electric vehicle charging,household appliances such as charging.It can also be used for mobile electric vehicle power supply,mobile robot power supply.Based on the equivalent mutual inductance model of MCRWPT system,the frequency characteristics,detuning mechanism and resonance state detection of the system are analyzed in this paper.This paper presents a frequency tracking method based on adaptive PI(Proportion Integration)control all-digital phase-locked loop,and the mathematical model of the phase-locked loop is established.The influence of PI control parameters on its performance is analyzed.In order to improve the speed and accuracy of frequency tracking,an adaptive fuzzy controller for adaptive adjustment of PI control parameters is studied.The frequency tracking method is realized by using FPGA(Field-Programmable Gate Array).Considering the situation that the resonant frequency of MCRWPT system deviates from the tracking range,a frequency of compound control method of MCRWPT system combined with dynamic compensation tuning control and frequency tracking control is proposed in this paper.Then,simulink is used to simulate the proposed compound control.Finally,this paper experiments on the MCRWPT system experimental device,and validates the frequency tracking control system.The experimental results show that the frequency tracking control system can make the system work in the resonant state when the resonant frequency is caused by the change of the circuit parameters.The transmission performance of MCRWPT system can be improved effectively by this way.