Research On Driving Charging Integrated Controller Of Electric Vehicle

Pure electric vehicle has two core technical problems,namely motor and its controller technology and battery and its charging technology,which have a deep impact on the performance and mileage of electric vehicle.Based on the topology of traditional electric vehicle motor controller,this thesis adopts the form of time-sharing multiplexing IGBT power module to expand the functions of the motor controller,so that the controller can realize the functions of motor drive and vehicle power battery charging at the same time.The structure of driving charging integrated controller is proposed and its working principle is described.The decoupling analysis is carried out at the topology level,and the mathematical models of two bidirectional converters in the integrated topology are established respectively,which provides a theoretical basis for the selection and design of control strategy.The mathematical model of bidirectional DC/DC converter is established based on small signal interference,and the equivalent circuit is drawn;Similarly,the mathematical model of bidirectional AC/DC converter established in three-phase static coordinate system is gradually deduced to dq coordinate system.The similarity of the equivalent mathematical models of the two bidirectional converters in different states also shows the feasibility of the integrated topology.In order to facilitate the design of the control system,taking into account the two modes,the parameters of the multiplexed intermediate energy storage elements in the topology are calculated.The decoupling analysis is carried out at the control level,and the control strategies under the two modes are determined respectively.Based on the established mathematical model,the double closed-loop control system is designed;According to the determined parameters of the intermediate energy storage element,the PI adjustment parameters are calculated,and the compensated open-loop amplitude frequency characteristic curve of the system is drawn by MATLAB.The processing methods of sampling signals and the similarity of current inner loop design between the two modes further prove the feasibility of the integrated controller.The simulation system is built in Simulink,and the simulation results verify the feasibility and effectiveness of the integrated controller.The hardware circuit and software program of the integrated controller are designed,and the integrated controller experimental platform based on TMS320F28335 is built.The resistive load is used to simulate the power battery,verify the charging mode,and analyze the waveforms of AC side voltage and current input,bus voltage and battery charging voltage;The driving mode is verified with5 k W permanent magnet synchronous motor as the load.The experimental results show that both modes can operate normally under rated working conditions.Through a series of calculation,design,simulation and experiments,this thesis verifies the feasibility of electric vehicle drive charging integrated controller,and provides a technical basis for its popularization.