Hybrid Fuzzy Fractional-Order PID-Based Speed Control for Brushless DC Motor

This article presents a novel hybrid control scheme for speed control of Brushless DC (BLDC) motor by simultaneously controlling BLDC motor reference current and inverter DC bus voltage. A fractional-order PID (FOPID) controller is employed to control BLDC motor reference current while a fuzzy logic controller manipulates the inverter DC bus voltage. A modified harmony search (HS) metaheuristic technique is developed for FOPID controller parameters tuning. Three different operating conditions are applied to test the motor, including no-load operation, varying load operation, and varying speed operation to verify the proposed controller's effectiveness. Furthermore, the proposed hybrid control strategy has been compared to Fuzzy-based and FOPID-based speed control schemes. The obtained results confirm that the proposed control scheme provides better and accurate speed control over a wide range of speeds. Also, the proposed controller decreases the torque ripples under different operating conditions.