Research On Sensor-less Control Technology Of High Speed Permanent Magnet Synchronous Motor

High speed permanent magnet synchronous motor(PMSM)has become the core part of high performance control system because of its excellent dynamic performance,high power density and high efficiency.The realization of the effective control of the motor requires high-precision rotor information.In view of the difficulties in installation,reliability and economy of the traditional mechanical sensor to obtain the rotor position information,the research on the sensor-less control technology of high-speed permanent magnet synchronous motor is becoming a hot research direction at home and abroad.In this paper,the research background and significance of the subject are briefly described,and the development of high-speed permanent magnet synchronous motor and its sensor-less control is also briefly introduced.On this basis,several common estimation methods of sensor-less control technology are listed.Through comparison and analysis,the estimation method of sliding mode observer which is easy to realize and has good robustness in engineering is selected.Secondly,the mathematical model of high-speed permanent magnet synchronous motor is established in three different coordinate systems.Based on the model,the vector control theory and space vector PWM technology of high-speed permanent magnet synchronous motor are studied deeply,and the vector control model of the motor is established,which verifies the effectiveness of the vector control strategy when the high-speed permanent magnet synchronous motor has position sensor.Then the basic theory of sliding mode variable structure is studied in detail.On this basis,the state equation is established according to the principle of sliding mode observer,and the real-time online estimation of rotor position and speed information is realized.At the same time,the low-pass filter is introduced,and the saturation function is used as the switching function to improve the chattering problem that may occur in the traditional sliding mode observer.At the same time,the simulation results of traditional observer and improved observer are compared to verify that the improved sliding mode observer has good robustness.In addition,in order to solve the problems of slow convergence and phase lag of the sliding mode observer,an integral term is introduced into the design of the sliding mode control rate,and a non singular fast terminal sliding mode observer is designed.The simulation model of the whole control system is built by MATLAB / Simulink.The simulation results show that the non singular fast terminal sliding mode observer has better performance.Finally,taking TMS320F2812 as the control core,the experiment platform of sensor-less control system of high-speed PMSM is built,and the design of software and hardware is completed.