Research On Sensorless Active Disturbance Rejection Control Of Permanent Magnet Synchronous Motor

Permanent magnet synchronous Motor(PMSM)has the characteristics of small size,high power factor,large starting torque,etc.,especially because the country attaches great importance to rare earth resources in recent years,making the manufacturing cost of permanent magnet synchronous motor gradually reduced,getting more and more development space,widely used in servo control system,as well as the field of new energy vehicles and rail transit vigorously promoted by the country.Obviously,in these fields,highperformance and stable speed control is pursued,position closed-loop is adopted,and the position and speed information of motor rotor must be obtained in real time.The traditional method is to use the position sensor to get the rotor position parameters,but it reduces the reliability of the controller,increases the manufacturing cost and control algorithm of the motor,so the use of sensorless control becomes another important research field of permanent magnet synchronous motor control.In addition,the load torque of permanent magnet synchronous motor will change continuously with time,and the parameters of motor stable operation,such as stator resistance and inductance,are easily changed in different working environment,which will seriously affect the robustness of the system.In order to overcome the influence of parameter changes on the control performance,the theory of ADRC is introduced into the control theory of PMSM,which has become a research hotspot of many scholars.In this paper,the sensorless control and auto disturbance rejection control technology of PMSM are studied based on the principle and practical demand.The specific work is as follows:(1)According to the complex actual mathematical model of PMSM in three-phase static coordinate system,it is transformed into a mathematical model easy to analyze in two-phase static coordinate system through the transformation of coordinate system.In the mathematical model of two-phase static coordinate system,the idea of motor vector control is described,and the derivation process of Clarke transform,park transform and Ipark transform is introduced in detail.Then the SVPWM technology is deduced and analyzed in detail,which lays the foundation for the use of sensorless technology to control PMSM,and paves the way for the development of ADRC technology.(2)For the zero and low speed condition of PMSM,the initial position of PMSM rotor is detected by pulse high frequency injection method.The voltage equation of dq axis of permanent magnet synchronous motor is established.The principle and realization of rotor position detection by rotating high frequency voltage injection method,rotating high frequency current injection method and pulse vibration high frequency voltage injection method are analyzed.The initial position detection system of PMSM rotor at zero speed is established,and the convergence of the system is analyzed.(3)For the high speed condition of PMSM,the basic principle of sliding mode variable structure control is introduced.Based on this principle,the mathematical model of the sliding mode observer is established.The corresponding control flow chart of the sliding mode system is given.The control algorithm without position sensor is briefly introduced,and the sliding mode observer structure is introduced into the position sensor free control system of permanent magnet synchronous motor for practical analysis.(4)Based on the above theoretical research,a parameter perturbation control strategy of PMSM Based on sliding mode observer compensation and auto disturbance rejection technology is proposed.Combined with the theory of sliding mode control,the dq axis sliding mode disturbance observer is constructed to observe the change of dq axis voltage caused by parameter perturbation and compensate it to the given dq axis voltage to improve the robustness of the system to parameter perturbation.The research of this paper enriches the algorithm of PMSM parameter perturbation control based on sliding mode disturbance observer compensation and auto disturbance rejection technology,which has certain guiding significance and reference value for the design of PMSM control system in practical situation.