Research On Model Predictive Direct Torque Control System Of Vehicle Permanent Magnet Synchronous Motor

The research and development of electric vehicles can effectively alleviate the energy crisis and environmental pollution.In the electric vehicle,the driving motor is the power source of the electric vehicle.Permanent magnet synchronous motor(PMSM)is widely used in electric vehicles as an efficient servo motor.Electric vehicles need frequent start and brake,acceleration and deceleration,uphill and downhill.Therefore,the driving motor is required to obtain stable speed in various situations,which puts forward higher requirements for the control of the driving motor.In order to improve the control effect of permanent magnet synchronous motor(PMSM),this paper introduces model predictive control(MPC)based on direct torque control(DTC),and proposes a model predictive DTC based on voltage vector subdivision.Firstly,this paper expounds the significance and purpose of the research on the control system of electric vehicle and its drive motor,analyses the research and development status of electric vehicle,electric vehicle drive motor,permanent magnet synchronous motor and their control methods,and expounds the main structure of the article;secondly,it introduces the structure of permanent magnet synchronous motor and the permanent magnet placement form of the rotor,and gives Yong Yong.Based on the coordinate transformation expression of AC speed regulation of magneto synchronous motor,the mathematical model of permanent magnet synchronous motor is deduced,and the whole mechanism of direct torque control of permanent magnet synchronous motor is given.Thirdly,the principle of model predictive control is introduced,and the model predictive direct torque control(MPDTC)of permanent magnet synchronous motor of electric vehicle is modeled and analyzed,and a new model based on MPDTC is proposed.The voltage vector subdivision model predictive direct torque control is used to further optimize MPDTC.A simulation model is built in MATLAB/Simulink software.The control effects of traditional DTC,MPDTC and MPDTC based on voltage vector subdivision are simulated and compared.It is concluded that the MPDTC based on voltage vector subdivision has better control effect.Finally,the hardware of permanent magnet synchronous motor is designed.With the software system,the selection of hardware function modules and the logical relationship between software control are expounded.The experimental platform of digital control system for permanent magnet synchronous motor is built.The PWM signal wave and rotor angle position are measured.The normal acceleration and deceleration experiments and the fast acceleration and deceleration experiments of the motor are carried out.And the current waveforms and torque waveforms under different control methods are experimented.Good experimental results are obtained.The experiment shows that the proposed MPDTC based on voltagevector subdivision is feasible.