Three-Phase DC–AC Converter Using Four-State Switching Cell

A new three-phase multilevel dc-ac converter with four-state switching cell is presented in this paper. Initially, the power stage diagram is presented and discussed. Its main characteristics are described and the more relevant waveforms, generated by simulation, are shown. After that, the converter operation is presented and all topological states are shown. The vectorial interpretation of the load voltage is shown to all available vectors of load voltage in the new topology. Next, the operation of the converter with sinusoidal pulse width modulation is discussed and some relevant figures are presented. In the sequence, the four-state switching cell is presented and the presence of the three-phase coupled inductor to provide significant reduction in harmonic distortion is discussed. A prototype with 15-kW output power was build with switching frequency equal to 9 kHz and dc link voltage was 300 V. Finally, the related results obtained from the implemented prototype are presented and briefly discussed.