Design of Speed Controller for Squirrel-cage Induction Motor using Fuzzy Logic based Techniques

This paper presents a performance based comparative study of various fuzzy logic controllers (FLCs) to control the speed of squirrel-cage induction motor (SCIM) by replacing the conventional proportional??integral (PI) controller. The fuzzy logic based controller does not require any identification of motor dynamic to control its speed and also assures the disturbance rejection with high robustness. Performances of the different fuzzy controllers (i. e. PD??, PI?? and PID??like ) are also compared with the conventional PI speed controller in terms of several performance measures such as peak overshoot (Mp%), settling time (ts), rise time (tr), steady state error (ess), integral absolute error (IAE), integral squared error (ISE), integral of time-multiplied absolute error (ITAE) and integral of time-multiplied squared error (ITSE), at different values of load (torque). The simulation results show the effectiveness of the controllers based on fuzzy logic techniques and, for each performance index, the PI??like fuzzy speed controller outperformed its conventional counterpart. Moreover, the performance of proportional??integral??derivative (PID??like) fuzzy speed controller is found best among all the fuzzy controllers discussed in this paper.