Dual inverter space vector modulation with power balancing capability

Dual two-level inverter topology is a simple structure capable to produce a multilevel voltage output equivalent to a 3-level inverter. Its modular structure consists of two standard two-level three-phase voltage source inverter (VSI) supplied by one or two DC sources. Known modulations cannot provide arbitrary power sharing between inverters in order to balance their dc voltages in case of two separate dc supplies. This paper proposes a new space vector modulation (SVM) technique for a dual two-level inverter which can provide load control of the two DC sources as well as multilevel voltage output. An original modulation algorithm has been introduced to regulate the dc-link voltages of each VSI according with the requirement of a control system, by means of a specialized space vector modulation. The proposed algorithm has been verified by experimental tests.