An Improved Predictive Current Control Strategy of Linear Induction Motor Based on Ultra-Local Model and Extended State Observer

Abstract

The Model Predictive Current Controls (MPCs) have fast speed response and low current’s Total Harmonic Distortion (THD) for Linear Induction Motors (LIMs) control. However, this method like other control methods has some disadvantages which one of them is the need to parameters detuning of LIM. On the other hand, parameters of the LIM are changed by changing condition like changing temperature. So, if the motor parameters are not been calculated accurate, the control of speed and THD of the current may become worse. In this paper, an improved MPC is proposed to solve this problem. The proposed Structure is resistant to changes in the parameters of the LIM. The proposed structure uses an ultra-local model instead of mathematical model of the LIM. Also, in the proposed structure, for estimate of disturbance and improve the control of speed, a Linear Extended State Observer (LESO) is used. According to the results, Proposed Structure have less ripple of speed’s path than Field Oriented Control (FOC), Conventional Direct Thrust Force Control (DTFC), DTFC-PI, Deadbeat-based Predictive Current Control (DPCC) and Conventional MPC. Also its ripple of the output speed is less than Conventional DTFC, DTFC-PI, DPCC and Conventional MPC. One of the other advantages of the proposed structure is fast speed of respond. In other word, in the proposed structure, actual speed achieves faster than FOC, Conventional DTFC, DTFC-PI, DPCC and Conventional MPC to the reference speed.