Design of feedback controller for soft-starting induction motor drive system using genetic algorithm

The objective of this work is to design and implement a closed loop system for induction motor starting at rated current. Thyristorized AC voltage regulator is used as the starting equipment and motor current regulation is carried out using an optimally tuned proportional-integral (PI) controller. Since AC voltage controller fed starting of induction motor is a non-linear process, identification of optimal values of PI controller constants is performed using genetic algorithm (GA). The complete drive system including AC voltage controller fed induction motor in conjunction with optimal PI controller is first simulated in MATLAB and subsequently verified experimentally. The successful implementation with a low cost microcontroller illustrates the feasibility of the new approach.