Comparison of Three Modulation Techniques for Single Phase Half Bridge 5-Level Diode Clamped Inverter Based on Level Shifted PWM

The switches of the inverter are operated by the control signal generated from the modulation techniques which are used to reduce the total harmonic distortion to improved output voltage quality. In this paper three modulation techniques based on a multicarrier level shifted PWM have been implemented, and the aim of this paper is to compare these three techniques to know how they effect on the output voltage quality of the inverter. The three modulation techniques are Sinusoidal Reference In Phase Disposition technique(S-IPD), Sinusoidal Reference Alternative Phase Opposition Disposition (S-APOD) and Sinusoidal Reference Phase Opposition Disposition (S-POD). These techniques are applied to the single phase half bridge 5-levels diode clamped inverter under different operation conditions. The study has been implemented via simulation using MATLAB/Simulink and setup experiments in the lab. The comparison between the simulation and experimental results are provided and discussed.