A sensorless drive system for brushless DC motors using a digital phase‐locked loop

Abstract

SUMMARYThis paper proposes a sensorless drive system for Brushless DC (BLDC) motors using a Digital PhaseLocked Loop (DPLL). The Back Electromotive Force (BEMF) voltage is measured from the motor winding to determine the permanent magnet rotor position using the DPLL, and Pulse Width Modulation (PWM) limits the motor current to control the speed of BLDC motors. The proposed method can drive BLDC motors using an openloop control without stepping out. Also, the proposed method is compared experimentally with a control method that uses Hall sensors. Experimental results for the BLDC motor show the effectiveness of the proposed method.

Direct torque control of PMBLDC motor using hybrid (GA and fuzzy logic) controller

“…The centre of area method has been used for the defuzzification. Investigation of sensor less direct torque control of PMBLDC motor using fuzzy logic controller has been successfully done [10]. However our proposed work aims at implementation of GA based fuzzy logic controller for the Direct Torque Control of permanent magnet brushless DC motor.…”