Abstract—Direct Torque Control is a control technique in AC drive systems to obtain high performance torque control. The conventional DTC drive contains a pair of hysteresis comparators. DTC drives utilizing hysteresis comparators suffer from high torque ripple and variable switching frequency. The most common solution to those problems is to use the space vector depends on the reference torque and flux. In this Paper The space vector modulation technique (SVPWM) is applied to Two level(2-L) inverter control in the proposed DTC-based induction motor drive system, there by dramatically reducing the torque ripple Then the controller based on space vector modulation is designed to be applied in the control of Induction Motor(IM)with a Three-level Inverter(3-L).This type o Inverter has several advantages over the standard two-level VSI, such as a greater number of levels in the output voltage waveforms, Lower dV/dt, less harmonic distortion in voltage and current waveforms and lower switching frequencies. This paper proposes ageneral SVPWM algorithm for threelevel inverter based on standard two-level inverter. The proposed scheme is described clearly and simulation results are reported to demonstrate its effectiveness. The entire control scheme is implemented with Matlab/Simulink.

Index Terms—DTC, Three-level Inverter, Two-level Inverter, Induction machine.

O.Chandrasekhar, is with the Department of Electrical and Electronics Engineering, Vignan’s Lara Institute of Technology & Science, Vadlamudi,Guntur, Andhra Pradesh ,522213, India (phone: +91 9440343273); Fax:+91 8632118456; e-mail: Sekhar.obbu@gmail.com.
Dr.K.Chandrasekhar,is with the Department of Electrical and Electronics Engineering,R.V.R&J.CCollege of Engineering, Chowdavaram,Guntur, Andhra Pradesh ,522019 India (phone: +91 9393194449);e-mail:cskoritala@gmail.com.

Cite: O.Chandra Sekhar and K.Chandra Sekhar, "Simulation and Comparison of 2-L & 3-L Inverter Fed Induction Motor DTC Drives," International Journal of Computer and Electrical Engineering vol. 3, no. 5, pp. 676-681, 2011.