Multilevel V3F Drive Application in Industries- A Survey and Comparison

ABSTRACT The multilevel inverter has gained wide importance in imperative applications because of reduction in harmonic distortion and switch stress replacing the conventional two-level converters. The selection of switching technique to control the inverter plays an important role on harmonic elimination while generating the ideal output voltage. Extensive survey has been performed on the industrial application of variable frequency drive using two-level and multilevel inverter ? in the selection of topology and control techniques, and the best control technique is suggested according to various application areas. In this paper comparison of SPWM, SFOPWM and SVM techniques applied on nine-level diode clamped multilevel inverter fed induction machine for industrial applications is presented for various modes of operation. In normal and high modulation indices SPWM and SFOPWM are preferable and in low and normal modulation index, SVM is preferred. The constant flux control method is used for speed control of induction machine.