Design of Brushless DC Motor Controller for an Electric Wheelchair

Design of Brushless DC Motor Controller for an Electric Wheelchair

  We introduce a design and implementation of brushless DC (BLOC) motor controller for an electric wheelchair. The control architecture consists of two layers of feedback control, namely the wheelchair posture control and the wheel velocity control. In the higher level of control architecture, the posture controller works as a reference velocity generator for the two wheels. We realize the joystick interface and the posture controller in an 8-bit microcontroller. It is on the lower layer that the velocity controller performs four quadrant operations. For the driving system, a DSP-based BLDC motor controller with three-phase inverter module is especially designed using only three Hall-effect sensors and a single dc-link current sensor. The functions of this motor controller include wheel velocity control and torque control. The performance of the control system has been verified experimentally.