Fuzzy Logic Aided PID Controller for Induction Motor Speed Control

This paper presents design of intelligent based controller for speed control of induction motor. The proposed system integrates a classical proportional-integral-derivative (PID) controller and intelligent algorithm based on fuzzy logic control (FLC). This scheme takes advantages of classical PID and FLC to improve the speed response performance of induction motor analysed in terms of transient and steady state time domain characteristics. The FLC designed was implemented using the fuzzy block of MATLAB/Simulink based on Mamdani model and comprises 9 fuzzy variables and 49 logic (intelligent) rules that define the system behaviour. The FLC takes the loop error and its rate of change to manipulate the input command to the PID control so that the response speed signal matches with the desired speed signal resulting in reduced rise time, peak time, settling time, overshoot, and improved steady state error. The designed intelligent aided PID controller was implemented and the simulation result provided a rise of time of 0.8354 second, peak time of 4.9615 seconds, settling time of 1.2240 seconds, final value (actual speed) of 1724.9 rpm, steady state error 0.1 rpm. Simulation comparison with conventional PID controller showed that the PID yielded a rise time of 1.6723 seconds, peak time of 4.5475 seconds, peak overshoot of 0.6913 %, settling time of 2.9646 seconds, final value (actual speed) 1736.1 rpm, and steady state error of 11.1 rpm. Generally, simulation results indicated that the intelligent (FLC) aided classical PID control improve the system performance and achieved the rated speed of the motor.