A simple method of tuning PID controllers for BLDC motor

In this paper, a robust control system with the sliding mode fuzzy controller and the additional PID compensator (PIDSMFC) is presented. The additional compensator relaying on the sliding mode theory is used to improve the dynamical characteristics of the drive system. Sliding mode fuzzy controller is studied because of its model free, stable and high performance. In this method, using high control gain to overcome uncertainties lead to chattering phenomena in control law which can excite unmodeled dynamics and may harm the plant. Different approaches, such as intelligent methods are used to abate these drawbacks. In order to enhance the sliding mode controller performance, fuzzy logic is used here. For this purpose, a PID outer loop is used in the control law then the gains of the sliding term and PID term are tuned online by a fuzzy system. Hence, the chattering is avoided and response of the system is improved against external load torque here. Presented simulation results confirm the above claims and demonstrate the performance improvement in this case.