Cascaded Fixed-Time Extended State Observer-Based Model-Free Predictive Control for PMSM Drives

To address the issue of deteriorated robustness in permanent-magnet synchronous motors (PMSM) caused by parameter perturbations, a model-free predictive current control (MFPCC) strategy incorporating a cascaded fixed-time extended state observer (FTESO) is proposed. First, an ultra-local model is established based on the motor current loops, and a fixed-time convergent observer is designed to enhance dynamic performance. Then, a cascaded structure is adopted to improve the observer’s disturbance estimation capability, thereby achieving higher precision in total disturbance observation. Simulation results corroborate the efficacy of the proposed observer.