High-Bandwidth and Strong Robust Current Regulation for PMLSM Drives Considering Thrust Ripple

This paper presents a high-performance current controller for the permanent-magnet linear synchronous motor considering the bandwidth and disturbances caused by the parameter variation and thrust ripple. First, an improved predictive current control (PCC) scheme based on the discretized model is proposed to increase the current control bandwidth. Besides the time-delay issue, it is noteworthy that the parameter variation in the PCC method can degrade the steady-state response. Through utilizing the information of first two sampling periods, the proposed PCC strategy can overcome such two issues at the same time. Second, a new discrete-time linearization observer is designed to estimate the thrust ripple. Then, the ripple can be suppressed by injecting the estimated value into the control system. Meanwhile, the stability analysis is given by the Lyapunov stability theory. A precise test platform based on the aerostatic guideway is established, and experimental results are shown to demonstrate the effectiveness and correctness of the proposed scheme.