Comparative Study of Integer- and Fractional-Order PID Controller Tuning for BLDC Motor Speed Using Single- and Multi-Objective Optimization

Abstract

This paper presents an optimal design of Integer- and Fractional-Order Proportional-Integral-Derivative (PID/FOPID) controller parameters for speed control of BLDC motor based on Single- and Multi-Objective Optimization (SOO/MOO). For SOO, the process of tunning was conducted via the Whale Optimization Algorithm (WOA) under Integral of Time Absolute Error (ITAE) objective function. At the end of SOO, the best solution which corresponds to PID/FOPID controller’s gains values has been obtained directly according to the minimum value of ITAE objective function. For MOO, the Multi-Objective Whale Optimization Algorithm (MOWOA) was used with three objective functions to minimize which are: settling time, overshoot and error steady state. The MOO generates non-dominated solutions forming Pareto front. The best compromise solution was obtained using fuzzy decision-making approach satisfying desired preferences. For the comparison of different controllers, step responses, frequency responses, tracking and load disturbance responses were all carried out and analyzed. The simulation results have shown that the MOWOA-FOPID controller provides a better response with faster speed without any overshoots, and good tracking capacity rejecting the load disturbances.