Model Reference Adaptive Control of a Permanent Magnet Brushless DC Motor for UAV Electric Propulsion System

In a previous work, a relationship between aircraft motion equations and model equations for a permanent magnet brushless DC motor was established to study the influence of machine dynamic performance on aircraft motion path from takeoff to steady level flight. The speed control scheme primarily made up of standard proportional integral controllers presented loss of altitude and exacerbative thrust when system was operated in speed control mode. In this paper a MRAC scheme is proposed for the speed control. It is shown that the application of the MRAC provides superior motor performance as well as an improvement in flight performance of the UAV system. The robustness of the control scheme to parameter changes in moment of inertia, viscous damping and load torque is shown.