Study of variation of total harmonic distortion in diode clamped multilevel inverter with modulation index

Abstract

Mutlilevel Inverter is a power electronic circuit used to generate voltage of multiple levels. As the number of levels increases harmonic content can be decreased. In this paper a three level diode clamped inverter is used and variation of its output total harmonic distortion with respect to modulation index is observed. Here Sinusoidal PWM technique is used to generate the pulse inputs to gate of IGBTs. In this method a fundamental frequency sine wave is compared with high frequency carrier triangular wave.