Research On Sensorless Control System Of Direct-driven PMSM

With the progress of the times and the development of science and technology,the new ball mill has outstanding advantages in price and performance compared with the traditional ball mill.Permanent magnet synchronous motor(PMSM)has the advantages of high efficiency,stable operation and good control effect,so permanent magnet synchronous motor(PMSM)is popular and industrial,because the technical difficulty of PMSM control is to detect the rotor position and speed of PMSM.The bad working environment of the ball mill has a great influence on the mechanical sensor installed on the rotating shaft of the motor.Therefore,the control system of the permanent magnet synchronous motor in the ball mill needs to use the method of non-code disk and other mechanical sensors to detect the real-time parameters of the motor.First of all,the sensorless algorithm control system of permanent magnet synchronous motor(PMSM)of ball mill is studied in this paper.Based on the basic principle of permanent magnet synchronous motor(PMSM),the theoretical equation of PMSM is established by its characteristics.The application of speed and current motor algorithm is explained in detail,and the calculation method control simulation system of motor non-mechanical sensor control is established on the platform of simulation software.Secondly,on the premise of the basic control principle of the motor,according to the classical extended Kalman filter theory,the speed and angle observer of the permanent magnet synchronous motor(PMSM)is established instead of the basic traditional motor control system.At the same time,because the calculation method of classical extended Kalman filter algorithm is more complex and the calculation is large,this paper uses the configuration of matrix parameters to assign special values to the state parameters of the system.The mathematical model of permanent magnet synchronous motor(PMSM)is completely linearized.An extended Kalman filter algorithm with fixed matrix parameters is established,which simplifies the calculation amount in the process of calculation.In the analysis of simulation process A new method is proposed to meet the requirements of the accuracy of motor speed and rotor winding angle estimation.Then,the sliding mode variable structure control theory is deeply studied,and the basic sliding mode observer is improved and optimized.Because the basic sliding mode observer has some shortcomings,such as noise and other interference in high frequency signal transmission,the prediction of internal parameters of the motor is not accurate enough and so on.In this paper,a continuous signal is proposed as a switching control function.At the same time,the estimation accuracy of motor rotor and the stability of the system are further optimized.The simulation diagram of the optimized extended sliding mode observer motor control system is designed on the simulation software platform,and the running performance and stability of the motor control system are analyzed effectively.Finally,the practical application of the new Kalman filter algorithm with fixed matrix parameters on the embedded control platform is proved by experiments.