고조파 주입을 통한 단상 3레벨 NPC 컨버터 중성점 전압 밸런싱 연구

A study on neutral-point voltage balance with harmonic component injection for single phase three-level NPC converter

This paper propse the DC link capacitor voltage balancing control for three level neutral point clamped converter with harmonic component injection method. The injcetion voltage consists of harmonic component and DC link capacitor voltage difference. Theoretical analysis is provided to balance the DC link voltage, and it shows that harmonic component compensates the unbalanced condition between the capacitors. Both simulations and experiments are carried out to show that the voltage unbalance have been decreased by the proposed method.