| Permanent magnet synchronous motor(PMSM)has a relatively simple structure.Compared with other motors,PMSM has higher reliability,higher efficiency,higher power factor,wider speed range and less loss.Therefore,it is often used in various control systems.Since the emergence of direct torque control system,due to the simple control structure,better control performance and strong robustness,the permanent magnet synchronous motor direct torque control system has attracted much attention.In this paper,the direct torque control system based on permanent magnet motor is studied in order to improve the control performance of the system,and to improve the efficiency of the motor in operation,to minimize the loss of permanent magnet synchronous motor,and to improve the utilization of energy.Based on the theory of direct torque control,a mathematical model of permanent magnet synchronous motor(PMSM)based on space vector pulse width modulation(SVPWM)technology is established.Aiming at the problems of excessive torque and speed ripple in traditional direct torque control system of permanent magnet synchronous motor based on space vector pulse width modulation technology,this paper presents an improved torque controller based on Super-twisting and a speed controller based on variable exponential reaching law,and establishes a corresponding control system based on the improved torque and speed controller.The simulation is carried out on MATLAB/Simulink.The simulation results show that the static and dynamic performances of the improved control system are improved,and the system-generated pulsations are effectively reduced,which verifies the effectiveness of the designed controller.Finally,in order to improve the utilization of resources,the operation efficiency of permanent magnet synchronous motor is optimized.Based on the loss model of surfacemounted permanent magnet synchronous motor(PMSM),a direct torque control system of PMSM based on optimal efficiency is established.The simulation experiment is carried out under MATLAB/Simulink.The results show that the operation efficiency of the motor with the optimal control system is improved and the energy loss is reduced. |
