Research On Model Predictive Control Of Dynamic Wireless Power Transfer System

Electric vehicles have the advantages of zero emission and low noise,which are attracting wide attention from all walks of life.In order to solve the problems of difficult charging and mileage anxiety in electric vehicles,dynamic wireless charging technology emerges as the times require.Conventional control algorithms are difficult to adjust rapidly when the coupling factor varies in a wide range,which leads to the instability of the system output current.In order to improve the regulation rapidity and power of the system in the dynamic process,the model predictive control(MPC)of the dynamic wireless power transfer system is studied and analyzed in depth.The main research contents are as follows:The soft switching realization condition of dynamic wireless power transfer system is analyzed,and a DC/DC converter is designed to improve the power of the system.The realization of soft-switching of inverters is the key for the high efficient operation of the system,and then the system is analyzed in detail,and the realization condition of soft-switching of inverters is deduced.From the perspective of improving the system power,BUCK converter is selected as the post stage circuit of the dynamic wireless power transfer system,and the corresponding control strategy is formulated.A linear state space model of the dynamic wireless power transfer system is established.The large signal model of DC/DC converter at energy receiver is non-linear,and it is difficult to process.So it is necessary to linearize the large signal model to get the small signal model and the linear state space model,and the linear state space model is selected to establish the prediction equation.The MPC algorithm with multi-step compensation is proposed,and the manipulated variables are optimized by analytical method.Sampling delay will cause a model prediction error,which will result in the oscillation of the control system.This problem can be effectively solved by delay compensation.In order to solve the problem that MPC algorithm causes a large amount of computation when it is employed to improve control accuracy,and the analytical method with low complexity and short computation time is derived.The research is carried out by the co-simulation of PLECS and MATLAB,and the experimental platform is built for testing.At different simulated speeds,the system under MPC has good dynamic characteristics,and the output current of the system changes smoothly.The MPC algorithm can improve the system power and adjustment speed under the high coupling state.In dynamic testing,the output current of the system with MPC algorithm is smooth.The simulation and experimental results verify the effectiveness and superiority of the dynamic wireless power transfer system with MPC algorithm.