Research On The Speed Control System Of PMSM For Electric Vehicle

Due to the continuous consumption and non-renewable of global resources and the increasing pollution of the environment,countries around the world have begun to conduct more and more in-depth research on new energy vehicles.Earlier,some car companies in Europe and the United States and some car companies in Japan started to study hybrid cars,but hybrid vehicles still have exhaust emissions.In view of these problems,these companies began to shift their targets to pure electric vehicles.In the process of researching electric vehicles,electric vehicles were gradually discovered.Many other advantages,such as the full utilization of energy,have developed to the present,more and more countries and auto companies have begun to invest in the research and development of electric vehicles,because there are still many bottlenecks in the battery technology of electric vehicles,so the focus of the research lies in the aspect of motor drive technology.In the selection of the drive motor,and taking into account China's national conditions and motor performance,most of the domestic car companies have chosen permanent magnet synchronous motor as the drive Motor.In this paper,the control of permanent magnet synchronous motor is studied by combining the sliding mode control method and the torque observer design.The main work of this paper is as follows:Firstly,the simplified dynamic model of the electric vehicle and the mathematical model of the permanent magnet synchronous motor are derived based on the theory.For the shortcomings of PID control such as overshoot and slow response,an improved global terminal sliding mode control method based on load torque observer is designed.The integral sliding mode and global terminal sliding mode control are used to replace the ordinary sliding mode,which improves the response speed.In the traditional Longberg load torque observation Based on the addition of the differential term,an improved load observer is designed to improve the fast response performance.Aiming at the problem of slow response of global terminal sliding mode control,the non-singular terminal sliding mode is used to improve,and the controller is designed to achieve accurate,stable and fast tracking of speed.Finally,according to the control method proposed in the paper,the simulation model is built in the simulation software and simulated.The simulation results are compared and analyzed to verify the effectiveness of the proposed method.The designed control system is combined with the dynamic mathematical model of the vehicle.Through the cycle conditions,the design method of this paper is tested and tested to verify the control effect of the controller designed in the paper.The simulation results show that the integral non-singular terminal sliding mode controller has faster running speed,better stability and less overshoot than the global terminal sliding mode design.Using NEDC cycle conditions,the simulation experiments of electric vehicles show that the non-singular terminal sliding mode improves the control effect of the controller,improves the control quality of the PMSM,and make the performance of electric vehicles better.