Optimal Fractional-Order Controller for Fast Torque Response of an Asynchronous Motor

As high-performance drives, asynchronous motor (AM) drives find extensive use in electric cars, elevators, and machine tools. For these applications, AM drives with direct torque control (DTC) are typically chosen over AM drives with field-oriented control because of their simplicity and quick torque control. Direct torque control of AM drives is frequently achieved using proportional–integral–derivative (PID) controllers. With variable set points and AM parameter ambiguity, these controllers perform poorly. New controllers called fractional-order controllers (FOCs) offer notable improvements over traditional PID controllers due to their enhanced flexibility, robustness, and fine control. In order to provide fast torque performance, this research suggests an AM drive that is regulated by direct torque control theory; nevertheless, the inverter control is optimized for fast response. On the other hand, by employing an optimized fractional-order PI (FOPI) controller, the AM drive speed response is enhanced. The particle swarm optimization (PSO) algorithm is used to optimize the FOPI’s parameters. The MATLAB/Simulink platform was used to model every part of the AM drive with the optimized control system. Three distinct controllers—optimized FOPI, standard PI, and optimized PI—were used to compare the performances of the introduced drive. According to the simulation results, the optimum response in terms of torque and speed was offered by the optimized FOPI controller. The average improvement in the settling time is about 84.4%, and that in the steady-state error is almost killed for all disturbances using the proposed optimized FOPI controller. Furthermore, under parameter uncertainties, the AM’s performance using the suggested optimized FOPI was examined. The outcomes of the simulation demonstrated how resilient the optimized FOPI controller was to changes in the parameters.