Fuzzy Based Digital Control Strategy for Four Quadrant Three Phase BLDC Motor with Speed Stability

The basic need in any speed control is to maintain the required speed even at load variations. In this paper, a novel fuzzy based speed control along with an existing PI control is added, in order to attain a fast steady state. Brushless DC (BLDC) motor drives are becoming more popular in industrial, traction applications. This makes the control of BLDC motor in all the four quadrants very vital. This paper deals with the digital control of three phase BLDC motor. The motor is controlled in all the four quadrants without any loss of power; in fact energy is conserved during the regenerative period. This digital controller with PI and fuzzy combination is very advantageous over other controllers .This control strategy is designed and simulated using matlab 7.10 with simulink model. The fuzzy rules are chosen based on the load current sensed through Hall Effect sensors.