Adaptive backstepping control for linear induction motor drive to track periodic references

An adaptive backstepping controller is proposed to control the mover position of a linear induction motor (LIM) drive to track periodic reference inputs in this study. First, the feedback linearisation theory is used to decouple the thrust forcc and the flux amplitude of the LIM. Then, an integral-proportional (IP) position controller is designed according to the estimated plant model to match the prescribed periodic step-command tracking specifications for the LIM drive. Moreover, a feedforward control is added to the IP control system for the tracking of periodic sinusoidal and triangular reference inputs. Although theoretically the feed forward control can track any time-vaiying reference, the robust control performance is degenerate when the uncertainties occur in the controlled plant. Therefore, an adaptive backstepping approach is proposed to obtain the robustness for uncertainties. With the proposed adaptive backstepping controllcr, the mover position of the LIM drive possesses the advantages of good transient control performance and robustness to uncertainties for the tracking of periodic reference inputs. The effectiveness of the proposed control scheme is verified by both the simulated and experimental results.