A new improved DTC of doubly fed induction machine using GA-based PI controller

This paper presents a new improved Direct Torque Control of doubly fed induction motor using PI controller tuned using genetic algorithm. The classical DTC control of DFIM is well known and is widely used due to its simplicity and easy implementation. However, the performances of conventional DTC are often characterized by high torque and flux ripples as well as variable switching frequency. To overcome the previous drawbacks of the classical DTC control, a new combined DTC-GA method using PI controller optimized by genetic algorithm is presented. The GA selects PI parameters that optimize the performances of conventional DTC. The PI parameters are optimized in offline mode where several values have been tested; then the best PI gains are used in online mode. The proposed DTC-GA method applied to DFIM has been validated using Matlab/Simulink environment. Many improvements related to torque and flux ripples overshoot and response time have been demonstrated. Which torque and flux ripple have been reduced more than 64.44% and 50 % respectively. The speed overshoot and torque overshoot have been reduced about 90% and 86% respectively. In addition, more details are presented and discussed in this paper. Keywords: Double Feed Induction Machine, Genetic algorithm, PI controller, Direct Torque Control, Reducing of torque and flux ripple