Research On Sensorless Direct Torque Control Of Permanent Magnet Synchronous Motor Based On Deadbeat

Due to structural characteristics and excellent performance,permanent magnet synchronous motor(PMSM)is widely used in aerospace,automotive research and development,industrial manufacturing and other fields.Direct torque control has the characteristics of simple system structure and fast torque response,which has attracted widespread attention.Aiming at a series of problems of overshoot chattering,weak anti-disturbance performance and limitations of mechanical sensors caused by the direct torque control system of permanent magnet synchronous motors(PMSM-DTC),this paper improves system control and sensorless control from two aspects.The sensorless control system of the permanent magnet synchronous motor based on deadbeat is as follows:Firstly,the development of permanent magnet synchronous motors and control strategies are described,then this paper introduces the research condition of sensorless control strategies and several common sensorless control strategies.Secondly,the principle of coordinate transformation is introduced and the mathematical models of motors in various coordinate systems are established,the principle of direct torque control is analyzed.The direct torque control system of the permanent magnet synchronous motor based on space vector pulse width modulation(SVPWM)is established.Simulations on the platform of MATLAB/Simulink verify its feasibility.Thirdly,to improve the system control link,the non-singular fast terminal sliding mode surface and variable exponential approach law are selected to design a new sliding mode controller for speed control.Based on the idea of deadbeat control,a discrete model of the motor is established,the flux linkage and torque deadbeat controller are designed based on the derivation of the voltage control law,the flux linkage is optimized to further improve the control performance.The simulation comparison and verification of the two controllers highlight the effectiveness and superiority of the deadbeat control strategy.Finally,to improve the system sensorless control link,a super-twisting sliding mode observer(STSMO)is designed based on the traditional sliding mode observer(SMO),which uses the super-twisting algorithm to design the control law and combines the phase-locked loop(PLL)technology to estimate the rotor position.Simulations verify the performance of the super-twisting sliding mode observer.The controller and observer of this paper are combined to establish a sensorless direct torque control system model of permanent magnet synchronous motor based on deadbeat.The simulation results show that the system has good performance and robustness under the conditions of motor startup and disturbance.