अमूर्त

A NOVEL DIRECT TORQUE CONTROL SCHEME FOR INDUCTION MOTOR DRIVE FOR REDUCTION OF COMMON MODE VOLTAGE

Mr.P.Nagasekhar Reddy

The Adjustable Speed Drives (ADS) are generally used in industry. In most variable speed drives Induction motor are generally used. The Direct Torque Control (DTC) technique has the feature of precise and quick torque response and reduction of the complexity of field oriented control (FOC) algorithms. In DTC, the generation of inverter switching state is made to restrict the stator flux and electromagnetic torque errors with in the respective flux and torque hysteresis bands so as to obtain the fastest torque response and highest efficiency at every instant. As the zero voltage vectors being used in conventional DTC the common mode emission are high. Hence to reduce these common mode emissions, a new DTC algorithm has been proposed in this paper. In the proposed method only odd active voltage vectors are used in odd sectors and only even active voltage vectors are used in even sectors. Thus, the zero voltage vectors have been eliminated in the proposed work. To validate the proposed method the simulation has been carried out in Matlab/Simulink environment and the simulation results are presented and compared. From the simulation results, it can be observed that the common mode emission has been reduced with the proposed DTC.