A robust control compensation for hardware deficiency in the plant: time delay control for the brushless DC motor drive

The time delay control (TDC) algorithm has been applied to the position control of a brushless DC motor (BLDCM) with a highly simplified hardware configuration: the six-step commutation was used without current control unit. Nevertheless, TDC achieves a performance level approaching to that of a BLDCM adopting sinusoidal commutation with current control unit. More specifically, the algorithm effectively compensates for parameter variations, nonlinearities, and the torque ripple caused by six-step commutation, whereas a conventional PID control yields poor response characteristics. This result shows that TDC enables an economical design without compromising performance. More importantly, the application establishes a case that a good control algorithm can compensate for the hardware deficiency in a given plant and even simplify its hardware configuration.