Adaptive High-Order Supercritical Sliding Mode Control for Position Tracking of PMLSM Based on Control Barrier Function

Sliding mode control (SMC) is widely used in permanent magnet linear synchronous motor (PMLSM) servo systems. However, improving the antidisturbance performance of SMC requires increasing the control gain, and excessive gain may induce severe sliding mode chattering. To resolve this trade-off, this manuscript proposes an adaptive high-order supercritical sliding mode control (AHOSSMC) method for PMLSM servo systems. By integrating high-order sliding mode control (HOSMC) with an adaptive gain strategy based on control barrier function (CBF), the conflict between disturbance rejection and chattering suppression is effectively mitigated, and the friction force in the PMLSM servo system is better compensated. Both the high-order sliding mode algorithm and the adaptive law are improved to enhance the performance of the AHOSSMC. Moreover, the switching behavior of the adaptive law is explicitly addressed to ensure continuous variation of the adaptive gain. Finally, comprehensive experimental validation is conducted to demonstrate the superior position tracking performance of the proposed AHOSSMC.