Design Of Wireless Power Transfer System Based On Improving Longitudinal Error Tolerance

With the increasing development of science and technology,it has brought technological revolutions one after another,and electricity demand is also increasing.In some special conditions,due to wireless power transfer(WPT)brings a lot of convenience,so it has received more and more attention from researchers.Especially the magnetic-coupled resonant wireless power transmission(MCR-WPT)system,which has large transmission power and high efficiency,has great advantages in energy transmission in the middle and long distance.So it has been becoming the focus research.However,the MCR-WPT circuit can achieve the highest efficiency transmission only in the resonance state.In the system detuning state,the transmission efficiency of the system will drop sharply,and most of the energy of the circuit will be lost.In this paper,improving the longitudinal fault tolerance rate during the MCR-WPT transmission process is studied.In order to improve the longitudinal error tolerance rate,the magnetic coupling resonance wireless energy transmission model is theoretical analyzed and simulation calculated.By simulating and analyzing the four topology compensation structures of SS,SP,PS,PP of MCR-WPT system,it is found that the topology compensation circuit of the SS structure best meets the design expectations.Therefore,based on the SS topology compensation structure,the four main factors affecting the change of the resonance frequency point are analyzed: the signal source frequency,the distance of the transceiver coil,the coil equivalent inductance and the resonance capacitor.Since the equivalent inductance of the coil is generally unchangeable,the adjusting the signal source frequency and resonance capacitance to compensate for the impact of the distance change on the system are mainly studied in our paper.Firstly,a wireless energy transmission system is designed,which compensates the system by adjusting the frequency of the signal source.The validity of the design is verified from both theoretical and numerical simulations.The relationship between frequency change,distance change and transmission efficiency is obtained.It is proved that the transmission efficiency of the system can be improved by adjusting the frequency.On this basis,a new dual voltage controlled variable capacitance circuit is proposed to adjust the size of the system's resonant capacitor.This method has greater adjustable range and higher the adjustment accuracy and withstand voltage.By combining the frequency adjustment and voltage controlled variable capacitance circuit adjustment methods,the new MCR-WPT circuit model is established.Finally,the actual circuit is built according to the simulated circuit structure,and the experimental data verified that the designed scheme can effectively improve the longitudinal fault tolerance rate of the system.