Abstract:
Brushless DC (BLDC) motors are commonly used in applications that require high reliability, high efficiency and high power-to-volume ratio such as industrial automations, manufacturing, robotics and aerospace. The speed of a brushless dc motor can be controlled in a closed loop by measuring the actual speed of the motor.PI (Proportional Integral), PID (Proportional Integral Derivative) and fuzzy controllers are commonly used for the speed control. This paper compares the speed responses of a brushless dc motor obtained with the adaptive fuzzy PID controller and conventional PI controller. The adaptive fuzzy PID controller proposed in the system is a parallel combination of two controllers- fuzzy PD controller and a fuzzy PI controller. Switching action take place between the two controllers based on the speed error signal received. MATLAB/Simulink is used for the simulation. Various control system parameters such as steady state error, rise time, peak overshoot, recovery time and settling time for both the controllers are analysed and compared.

Keywords: Brushless DC Motor (BLDC), PI Controller, Adaptive fuzzy, speed control, PWM inverter