Position Sensorless Active Disturbance Rejection Control Of PMSM Based On Improved Sliding Mode Observer

Permanent Magnet Synchronous Motor(PMSM)is widely used in new energy vehicles and other industrial fields by virtue of its advantages such as small size,light weight,and excellent torque output characteristics.Because in the traditional double closed loop adopting traditional PI control system,there are contradictions between response speed and overshoot.At the same time,the position or speed sensor needs to be embedded in the motor,which will cause problems such as difficulty in control and cost.In order to solve these problems,this thesis has carried out research on PMSM sensorless control strategy.This article first introduces the types of PMSM,derives the conversion between three commonly used coordinate systems and the mathematical model of PMSM in three different coordinate systems,selects the implicit PMSM as the research object,and analyzes the basic principles of PMSM vector control.Derived and calculated Space Vector Pulse Width Modulation(SVPWM)technology and double closed loop using traditional PI parameter adjustment.Secondly,in order to solve the problem that the control system using traditional PI as the dual closed-loop control cannot meet the control requirements,the sliding mode variable structure control is introduced,and the current sliding mode observer based on the sliding mode variable structure control is designed,and the arctangent function is used to determine the rotor position and speed.Estimated to achieve sensorless control.In order to solve the chattering and phase delay problems that exist in the traditional sliding mode observer,the switching function of the current sliding mode observer adopts the Sigmoid function,and the adaptive parameter identification is used to identify the resistance and inductance of the motor on-line.These identified parameters are introduced into the current sliding mode observer to design an adaptive current sliding mode observer,and then the phase-locked loop is used to estimate the rotor position and speed.The improved sliding mode observer suppresses chattering and phase delay problems,but still has certain defects in motor loading and anti-disturbance.Finally,the MTLAB/Simulink and RT-LAB simulation platforms are used to simulate and experimentally verify the control system.The results show that the experimental results are basically consistent with the theoretical design.The designed sensorless control system suppresses chattering,eliminates phase delay and other issues,and has good antidisturbance and load-carrying capabilities.