Model-free adaptive sliding mode compensation predictive control of PMSM based on load prediction for energy saving

To address the energy efficiency challenge of "oversized motors driving light loads" in coal washing plant conveyor systems, where permanent magnet synchronous motors (PMSM) frequently switch between no-load, light-load, and full-load states under varying material flow rates, this paper proposes a differential-enhanced model-free adaptive sliding mode predictive control strategy. First, a dynamic prediction model is established using time-varying pseudo partial derivatives derived from the motor's torque-electromagnetic-voltage kinetic equations. The original control architecture is augmented by integrating a differential compensation term into the predictive data model to enhance transient response and mitigate oscillations. A high-order sliding mode compensator is then designed based on the prediction-actualization error, synergized with pseudo partial derivative estimation to formulate dual-loop current-speed controllers. MATLAB/Simulink simulations confirm that the improved controller achieves superior dynamic performance in settling time, overshoot suppression, and disturbance rejection compared to the baseline method, while maintaining operational stability. This approach offers a viable framework for energy-optimized motor control in industrial systems with unmodeled load variations.