Research On Sensorless Control Of High-speed Permanent Magnet Synchronous Motor

High-speed surface-mounted permanent magnet synchronous motor(HSPMSM)has the advantages of small size,high efficiency,high power density,low rotational inertia,fast dynamic response and wide speed regulation range.They are widely used in flywheel energy storage systems,high-speed spindles,turbomolecular pumps,gas compressors,and industrial blowers.However,as the rotor speed of the motor increases,its carrier ratio(the ratio of inverter switching frequency and motor running frequency)decreases,which leads to an increase in current harmonics and affects the dynamic performance of HSPMSM.Meanwhile,in some high-speed situations,the mechanical position sensor may not be able to obtain accurate rotor position information.Therefore,the accurate observation of the HSPMSM rotor position angle is crucial for the control system.Based on this background,this paper investigates the sensor-less control strategy of permanent magnet synchronous motor under high speed operating conditions by taking the surface-mounted high speed permanent magnet synchronous motor as the research object,as follows.First,in order to obtain an accurate mathematical model of the motor,a highspeed permanent magnet synchronous motor model based on direct discretization is constructed in this paper,and based on this mathematical model,an adaptive discrete full-order sliding mode observer of the back-electromotive force is designed to obtain a more accurate back-electromotive force component.Secondly,the observed estimated back-electromotive force values are input into a discrete synchronous fundamental frequency extraction filter to further weaken the influence of harmonics on the estimated back-electromotive force values.Then,a fuzzy feed-forward phaselocked loop control method based on the discrete domain is proposed.This method is based on applying the fuzzy PI regulator to the feed-forward phase-locked loop control in the discrete time domain,and adjusting the proportional integration coefficient of the phase-locked loop PI regulator by the fuzzy controller so that the phase-locked loop PI regulator can have better steady-state performance over a wide range of motor speeds,using the feed-forward phase-locked loop to reduce the acceleration operation as well as the The feed-forward phase-locked loop is used to reduce the steady-state position tracking error under acceleration and load disturbance,and to improve the dynamic steady-state performance of the HSPMSM.Finally,Matlab simulation analysis of the research object is carried out by using the combination of a discrete full-order sliding mode observer with synchronous frequency extraction filter and a fuzzy feed-forward phase-locked loop control method,and the proposed algorithm is verified on the d SPACE based high-speed permanent magnet synchronous motor experimental platform.