Research On PMSM Control System Based On SMO

With the rapid development of advanced control technology and the high-performance MCU,permanent magnet synchronous motors(PMSM)are becoming more and more widely used.In order to achieve high precision and high dynamic performance of PMSM control,the closed loop of speed and position is indispensable.At the same time,the installation of mechanical speed and position sensor often increases the volume and weight of the system and increases the cost.Therefore,these factors limit the application of PMSM in some special occasions,and the sensorless control technology can well overcome these shortcomings.Because of its simplicity and ease of engineering implementation,SMO has been widely used in the field of motor control.However,this method has the phenomenon that the state trajectory traverses back and forth on both sides of the sliding surface,and chattering is generated,which limits its application.For the problem of the high-frequency buffeting of the traditional SMO,this thesis introduces the saturation switching function and the base-phase injection phase-locked loop(PLL)to weaken the sliding mode high-frequency chattering component and improve the system response.By designing the sliding mode gain adaptive law,the application range of the SMO is expanded.In this thesis,the influence of stator resistance change on the control performance of the designed SMO is studied.The online identification module of stator resistance is introduced to improve the anti-interference performance of the SMO.Based on the improved SMO of PMSM sensorless control system,this thesis studies the improved PI speed controller and disturbance compensation principle for PMSM vector control system.Based on this,combined with the fuzzy control strategy,an improved fuzzy PI speed controller is designed,and the load disturbance observer is introduced to observe the motor load disturbance in real time.The anti-load disturbance ability of the system is improvedIn order to verify the correctness of the design method,the MATLAB simulation model of PMSM sensorless control was built.The control effect of the improved SMO was compared and the control performance of the designed improved speed controller was discussed.The simulation results show that the chattering problem in the improved SMO designed in this thesis can be suppressed and has good robustness.The improved speed controller can achieve better control effect.Moreover,it can be combined with the SMO to form a stable PMSM position sensorless control system,which has certain value of application.Figure [60] table [6] reference [55]...