Variable slip-frequency strategy for reducing non-equal deviations output by paralleled single-sided linear induction motors

A predictive variable slip-frequency (PVSF) control strategy is presented to reduce non-equal output thrust deviation even though the existence of primary imbalancing input current is allowed. Besides current and speed sensors, the proposed strategy takes no additional sensors for that it only employs the real-time speed signal and the latest instantaneous slip-frequency to generate the predictive dynamical slip-frequency corresponding to deviation of thrust output by paralleled single-sided linear induction motors (SLIMs) groups. Owing to its insensitive to primary current d/q axes components for the generation of variant slip-frequency, the PVSF strategy owns a significant anti-noise ability since as big inertia system, the speed of parallel SLIM groups cannot vary abruptly. Both simulations and experimental results verify the feasibility of the proposed PVSF strategy.