The Differential Algebra Sensorless Control For PMSM Drive System

Permanent magnet synchronous motor(PMSM)has been widely used in industry,home appliances,automobile and other fields because of its advantages of high efficiency and high power density.At present,field oriented control(FOC)is widely used in PMSM drive system to realize decoupling control of torque and excitation.FOC is based on coordinate transformation,so it is very important to obtain rotor position accurately in real time.The mechanical position sensor will increase the cost and volume of the drive system.At the same time,it is easy to be interfered by temperature and electromagnetic noise,which reduces the reliability of the system.Therefore,in recent years,sensorless control has increasingly become a research hotspot in the field of PMSM drive systems.In this paper,the position and speed estimation of surface mounted permanent magnet synchronous motor(SMPMSM)drive system is realized by using differential algebra sensorless control.At the same time,the Tracking Differentiator is designed and the arctangent function is solved by segments to improve the estimation accuracy of rotor position and speed.After that,the differential algebra sensorless control method is extended to the IPMSM drive system to achieve high precision rotor position and speed estimation.The sensorless control based on differential algebra is highly dependent on motor parameters.Firstly,this paper analyzes the reasons of the motor parameter changes,and realizes the multi parameter online identification of SMPMSM drive system based on algebraic parameter identification method.Then,the motor parameters in differential algebra sensorless control are updated by using the results of parameter identification,and the differential algebra sensorless control scheme of SMPMSM drive system integrated parameter identification is proposed.In addition,the paper takes sensorless control as a redundant design for rotor position detection,thus constructing a fault-tolerant control scheme for the position sensor of the SMPMSM drive system.This method significantly improves the operational reliability of the SMPMSM drive system.The nonlinearity of the inverter in the SMPMSM drive system directly affect the rotor position estimation accuracy of the differential algebra sensorless control.In this paper,the cause of inverter nonlinearity and its influence on differential algebra sensorless control are analyzed.A model free observer is proposed to observe the disturbance voltage caused by inverter nonlinearity.Then,the reference voltage feedforward compensation of differential algebraic sensorless control is used to improve the nonlinearity of inverter.Finally,the sensorless driving system of SMPMSM integrated inverter nonlinear compensation is constructed.On the basis of theoretical research,this paper establishes the mathematical model of SMPMSM drive system based on MATLAB,and carries out simulation research on the proposed sensorless control method,so as to verify the effectiveness and feasibility of the proposed method.