Multi-level inverter capable of power factor control with DC link switches

This paper proposes a new multi-level inverter topology based on a H-bridge structure with four switches connected to the dc-link. Based on a POD (Phase opposition disposition) modulation method, a new PWM method which requires only one carrier signal is suggested. The switching sequence to balance the capacitor voltage is also considered. In addition to these, the proposed topology requires minimum number of component count to increase the number of voltage level. Operating principle of the proposed inverter is verified through simulation and experiment.

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