Model-based fault detection for a brushless DC motor using parameter estimation

A real time fault detection for a brushless DC motor driving a mechanical actuation system is presented. The brushless DC motor is controlled by a PWM inverter using rectangular current excitation. After an introduction into fault detection with parameter estimation, a mathematical model for the actuator with special emphasis on the motor itself is derived. The application of the estimation algorithm to detect electrical parameter changes in the motor using single phase currents is described. The fault detection scheme is implemented on a digital signal processor controlling the actuator. Finally experimental results are given.