Implementation of 12 Sector Fuzzy Controller for Direct Torque Control of Induction Motor

The induction motor has a wide range of industrial application attributed to its robust construction, simplicity in design and cost-effectiveness. For achieving the best potency of the motor several methods of management have developed in the course of time. Of these direct torque control (DTC) has gained importance due to its fast torque control of induction motor. A key feature of DTC is its ability to control flux linkage and electromagnetic torque in direct and independently by proper selection of voltage vectors. However conventional DTC has several shortcomings such as high ripple contents in torque and flux and inconsistent switching frequency. This paper discusses the strategy to overcome the high ripples content in torque and flux. A novel strategy for selection of optimum voltage vector from a fuzzy controller which has the flux locus divided into 12 sector compared to the conventional 6 sector. The predictive method for voltage vector and the 12 sector concepts has been modelled and simulated, and their results have been reported in this paper.