Two Compact Three-Phase Multilevel Inverters for Low-Voltage Applications

In this article, two compact three-phase multilevel inverters are proposed. The first proposed topology consists of three dc sources and ten power switches. The merit of the first proposed topology is reducing two switches from its structure to the conventional topologies. The second proposed topology is similar to the first one, except that one of the dc sources is replaced by a capacitor. This capacitor is balanced by an additional switch and one of the dc sources. How to apply two modulation methods for these inverters has been studied in detail. These modulation methods are level-shifted pulsewidth modulation and phase-shifted pulsewidth modulation (PS-PWM). Also, the value of the capacitor for each of the modulation methods has been calculated. Finally, the experimental results are provided to confirm the performance of the proposed topologies.