The Three-Phase Converter with Configurable DC Input and Multilevel AC Output

The article presents a three-phase voltage converter with a configurable DC (Direct Current) input and an AC (Alternating Current) output, which uses magnetically coupled reactors. The described converter is characterized by the ability to produce a multi-level, three-phase output voltage with a low THD (Total Harmonic Distortion) content. Due to the possibility of configuring DC inputs, the proposed converter may enable easier integration of renewable energy installations with the power system. The paper [19] presents the operation of magnetically coupled reactors with voltage inverters as an electrical concentrator, while the presented work presents a modulator that, together with magnetically coupled reactors and voltage inverters, allows changing the frequency of the output voltage and controlling the current. In this view, the presented system can be considered a new DC/AC converter with multiple DC inputs and multi-level and three-phase AC output. Experimental studies of the basic structure of the converter and simulation studies of selected variants of the system's cooperation with two-level voltage inverters are presented. The use of magnetically coupled reactors enabled the use of a magnetic system with lower power and dimensions.