Research On Sensorless Control Technology Of Permanent Magnet Synchronous Motor

Compared with ordinary AC motor,permanent magnet synchronous motor(PMSM)has the advantages of high efficiency,small size,light weight and good quietness,which has been widely used in the field of industry and agriculture.At present,PMSM speed control system mostly adopts double closed-loop vector control system.When the load changes with the given speed,the speed loop PI regulator still has some shortcomings.At the same time,the installation of mechanical sensor not only increases the cost of control system,but also limits the application of motor.In view of the above two problems,the main contents of this paper are as follows:Firstly,the structure classification and mathematical model of PMSM in three coordinate systems are introduced.According to vector control principle and space vector pulse width modulation technology,PMSM vector control system is established and its correctness is verified.Aiming at the shortcomings of traditional PI speed controller,the sliding mode control(SMC)theory and exponential reaching law are used to design the sliding mode speed controller.In order to reduce the influence of load disturbance on the system,the extended state observer(ESO)is used to improve the sliding mode speed controller,and a load feedforward compensation SMC controller is designed.The simulation results show that the designed sliding mode controller can improve the antiinterference ability of the system.Secondly,the extended Kalman filter(EKF)is analyzed,and the multi innovation identification theory(MIIT)and EKF are combined to establish the PMSM sensorless control system model based on multi information extended Kalman filter(MI-EKF).The simulation results show that MI-EKF can effectively improve the estimation accuracy.At the same time,the SMC controller based on load compensation is applied to the MI-EKF sensorless system.Simulation results show that the improved SMC controller can effectively suppress the speed overshoot and load disturbance compared with PI controller.Finally,TMS320F28335 is used as the control core of the speed control system,and the hardware and software of PMSM speed control system are designed.Figure [50] table [6] reference [69]...