Reduction in Commutation Torque Ripple in Sensorless Bldc Motor Using Fuzzy Logic Controller

Brushless Direct Current (BLDC) motors are widely used due to high reliability, simple frame, straight forward control, and low friction. BLDC motor has the advantage of high speed adjusting performance and power density. Speaking of the motor drive, the most important part is commutation control. On the other hand, they show a high torque ripple characteristics caused by no ideal commutation currents. This limits their application area especially for the low-voltage applications. In order to minimize torque ripple for the entire speed range, a comprehensive analysis of commutation torque ripple was made according to phase advancing(PA) commutation control method. This approach is based on the terminal voltage sensing and converting the voltages into d-q reference frame and the commutation signals are generated by comparing it with reference values. The gating signals are obtained by switching sequence of BLDC motor and it is done using fuzzy logic controller(FLC).The design analysis and simulation of the proposed system is done using MATLAB version 2013a and the simulation results of proportionalintegral (PI) controller and fuzzy logic controller(FLC) method is compared.