<p>To further promote the transient response and disturbance rejection capabilities of permanent magnet synchronous motor (PMSM), an improved fixed-time sliding mode-based predictive function control (IFTSMPFC) is proposed. Unlike existing PFC approaches for pure speed loop regulation, the proposed IFTSMPFC is adopted for speed and current single-loop control, rather than the conventional cascaded control structure. Firstly, a new prediction model that incorporates external interference and parameter mismatches into a disturbance term is constructed. Then, a novel cost function is designed using fast sliding mode technology with an improved fixed-time reaching law and a current constraint module is introduced. Next, a discrete-time fixed-time extended state observer (FTESO) is developed to achieve accurate estimation of the lumped disturbance, which is compensated to the predefined cost function. Finally, experimental results demonstrate that the proposed method achieves good dynamic performance, low overshoot, and strong robustness against external disturbances and parameter variations.</p>