A space vector modulation strategy for three-level operation based on dual two-level voltage source inverters

This paper presents a space vector modulation (SVM) technique for a three-level operation based on dual two-level voltage source inverter (VSI). This inverter topology uses two standard two-level VSI placed in parallel using a three-phase transformer to connect them together. This paper proposes a general modulation algorithm for dual two-level VSI based on the basic two-level SVM technique. The proposed inverter produces five-level line-to-line voltage waveforms, which is able to generate voltage levels similar to a three-level inverter. The practicality and performance of the modulation strategy for the proposed inverter topology has been verified via simulation and experiment.