Research On Control Strategy For Parameter Identification And Disturbance Rejection Technology Of Wireless Power Transfer

Wireless power transfer(WPT)technology has been widely applied in domestic appliances,biomedical engineering,consumer electronics and industrial machinery,owing to its advantages of flexible,safe and wire-free connection for power supply.Along with WPT technology becoming a research focus,higher requirements and standards for this technology have been put forward.However,wireless power transfer system will be affected by the external environment in the practical application.In addition,the parameters uncertainties of circuit elements and abruptly varied load will cut down the control effect of WPT system.Therefore,effective control algorithms are imperative to be designed to solve the control problems when WPT system encounters different situations,and to improve the transmission efficiency and enhance system robustness.After the introduction of the basic principle and the research focuses on WPT technology,this thesis summarizes the previous research status.Meanwhile,through the analysis of topology and power transmission properties of magnetic coupling resonant-WPT system,the overall design scheme of WPT system is constructed.The mathematical model of wireless power transfer unit is established thereafter,according to the topology of system.First,the parameter uncertainty of WPT system is studied through Particle Swarm Optimization(PSO).PSO algorithm with inertia weight is used to identify and estimate the variant mutual inductance of the coupling coils.The precise parameter of the system model will be identified through the intelligent algorithm.Secondly,with a fixed mutual inductance,adaptive backstepping control strategy for WPT system is proposed to deal with the uncertainty or mutation of load impedance.The uncertain load parameter can be estimated on-line and the output tracking control problem will be analyzed.At last,for the power output module of WPT system,a class of sample-data feedback controller is designed to solve the problem of output voltage fluctuation when load impedance changes suddenly.The stability of output voltage and disturbance rejection will be verified by simulation and experimental results.