Multilevel inverter are used in various applications in recent times for medium/low voltage and high power. The main reason behind use of multilevel inverter it has better total harmonic distortion (THD) and attain high values of voltage. Main issue in multilevel inverter diode clamped topologies is dc link capacitor voltage balancing. In this paper, method for dc link capacitor voltage balance for three level neutral point clamped inverter using level shifted multicarrier sinusoidal pulse width modulation is considered. Proposed method not only balances capacitor voltage but also reduces harmonics in load voltage and current. The performance of proposed topology is verified by simulation and experimental results.

Keywords : Bias value(B),Diode clamped inverter(DCI)/Neutral point clamped inverter (NCI),Multicarrier sinusoidal pulse width modulation(SPWM),Multilevel converter, Total harmonic distortion(THD).