Switching Technique for Dual-Two level Inverter Supplied by Two Separate Sources

A multilevel inverter topology feeding three-phase open-end winding loads is considered in this paper. The scheme is based on two insulated dc supplies, each one feeding a standard two-level, three-phase inverter. A three-phase six-wire load is connected across the output terminals of the two inverters. A new modulation technique able to regulate the sharing of the output power between the two dc sources within each switching cycle is presented. The performance of the whole system has been verified by experimental tests.