Modified field oriented control for smooth torque operation of a BLDC motor

This paper describes a novel approach to field oriented control of a BLDC (Brushless Direct-Current) motor producing a significantly reduced torque ripple. This paper presents a standard mathematical model of a BLDC motor in the abc reference frame which is suitable for simulation of the six-step control strategy, and a mathematical model of a BLDC motor in the dq reference frame suitable for standard and modified field oriented control strategies. An extended dq transformation, in other words a Park's-like transformation, is described and implemented in the simulation model. Simulation results of all the control strategies are evaluated and compared.