Vector Control System Study Of Permanent Magnet Synchronous Motor In Electric Vehicle Driving

The rapid development of the real economy and the virtual economy has caused serious damage to the environment and a worldwide crisis of energy shortage.Governments are striving to support the development of new energy vehicles.The advantage of electric vehicles is zero emissions,no pollution,and the source of power from batteries.Therefore,the promotion and development of new energy vehicles represented by electric vehicles has become an important measure for countries to solve this global problem.The motor drive control determines the power performance of the electric vehicle and also affects the safety of the vehicle.In this paper,the permanent magnet synchronous motor(PMSM)with high torque inertia ratio and high operating efficiency is selected for analysis.Through the description of the three control strategies of the permanent magnet synchronous motor and the analysis of the control problems in the actual operation of the electric vehicle,the vector control strategy is used to control the operation of the PMSM.The speed loop is based on the sliding mode variable structure vector control.The system realizes precise control of electric and ring within the speed.Then the mathematical model,coordinate transformation and implementation of SVPWM algorithm of permanent magnet synchronous motor are elaborated,which provides a powerful theoretical basis for analyzing and researching the driving strategy of electric vehicle.Then it focuses on the related theory of sliding mode variable structure control and the design method of sliding mode controller.The MATLAB software was used to model and simulate the speed loop of the PMSM vector control system using PI control and speed loop based on sliding mode variable structure control.The simulation results were analyzed and compared,and the PMSM based on sliding mode variable structure control was obtained.The vector control system has better dynamic performance and stronger robustness.Finally,the software part of the PMSM control system and the hardware part of the driver are designed.The hardware part of this system mainly includes the system main circuit,control circuit and sampling circuit.The software section gives the block diagram of the main program and interrupt subroutine and the SVPWM program flow chart.Finally,the system debugging work is carried out,and the feasibility of the vector control system is verified.