A Configuration for Output Voltage Boost of a Three-phase, 3-Level Multilevel Level Inverter

This paper presents a three-phase multilevel voltage source inverter designed to boost the output voltage. In each phase, the proposed inverter is configured by inserting a capacitor bank at the output terminals of a modified H-bridge. With this configuration, 3 level phase-leg output voltage waveforms, whose peak values are twice the single-input voltage magnitude, can be generated; resulting in the syntheses of 5 level output line voltage waveforms. Low frequency switching scheme based on Fourier series analysis is used for the inverter control operation. The salient feature of the proposed circuit is its output voltage boosting capability and reduction in diode current path and hence conduction losses. The performance of the proposed inverter configuration is demonstrated through MATLAB/SIMULINK simulations and experimental results on a laboratory prototype with a DSP-based controller.