Reseach On Control System And Sensorless Control Method Of Linear Ocsillatory Motor

Compared with the traditional rotary motor,the linear oscillating motor cancels the crank linkage structure and directly drives the actuator to make the reciprocating linear motion,thus greatly improving the control efficiency.At the same time,as the main energy-consuming components of air conditioners and refrigerators,the optimization of linear oscillating motor is of great significance for energy conservation and emission reduction.In this paper,the control system of linear oscillating motor is studied deeply with the aim of improving the accuracy of linear oscillating control,improving the anti-disturbance and reducing the cost of linear oscillating motor.This paper first introduces the basic structure and working principle of linear oscillating motor,and establishes three basic models of linear oscillating motor,namely electromagnetic system model,dynamic model and circuit model.Then the control platform of linear oscillating motor is built,which includes the overall architecture of the driving platform and the concrete realization of the control circuit,driving circuit and conditioning circuit.The upper computer software is built to monitor the running state of the motor.Then in view of lower controlling precision of conventional PID control algorithm,the high phase delay,and poor resistance to disturbance problems.This paper puts forward the position –velocity single outer loop and current inner loop double closed loop model algorithm structure and extended state observer as a complement,effectively improve the control precision of the linear oscillation motor,reduce the phase delay and increase the ability to resist load disturbance.At the same time,the reliability and stability of the algorithm are theoretically analyzed and proved.Simulation and experiment show that the control algorithm can effectively improve the control performance of the motor.At last,the estimation algorithm of gradient correction parameter is put forward to solve the problem of time varying of parameters in the running process of motor,which is difficult to track the change directly and the electromagnetic thrust coefficient is difficult to measure directly.The algorithm can effectively track the real-time change of motor parameters and directly measure the electromagnetic thrust coefficient,effectively solving the requirement of parameter accuracy in the subsequent position observation.Aiming at the problems of high cost and wasted space of position sensor,a method of Kalman observer is proposed to observe the position information of linear oscillating motor and a mathematical model of Kalman observer is built.Simulation results show that this method has high accuracy and can effectively observe the position information of linear oscillating motor.