Multilevel voltage source inverter with coupled reactors using coarsely quantized pulse amplitude modulation

Abstract

The paper discusses a multilevel voltage source inverter with coupled reactors (MVSI-CR). The output voltage is generated using the novel coarsely quantized pulse amplitude modulation (CQ-PAM). The AC voltage synthesis is realized by selecting and applying an appropriate collection of voltage vectors from the space-vector diagram. Integrating classical two-level inverters allows for achieving modularity of the solution. The main advantage of the proposed approach is a very low switching-to-fundamental frequency ratio and a multistep quasi-sinusoidal output voltage. The paper includes a theoretical analysis, simulations, and laboratory test results.