Modified SVPWM for Three-Phase Six-Switch Switching-Cell Current Source Inverter

This article proposes a three-phase six-switch switching-cell current source inverter (H6-SC-CSI) and a modified switching scheme of space vector pulsewidth modulation (SVPWM). Compared to the conventional three-phase six-switch current source inverter, the H6-SC-CSI has no open-circuit possibility, thus, the inverter reliability is greatly enhanced. In addition, the overlap-time can be minimized; hence, the output waveform quality can be considerably improved. Due to the presence of switching-cell capacitors, a conventional switching sequence of the SVPWM is modified for the inverter to operate properly. A 2.2 kW hardware prototype is built and tested to verify the effectiveness of the proposed PWM.