This paper presents a switching strategy for improving lifetime of DC-link capacitors in photovoltaic (PV) hybrid active neutral-point-clamped (ANPC) inverters. The DC-link capacitor current ripples should be reduced, because the high current ripples of the capacitors cause high thermal stress and short lifetime of the capacitors. To reduce the DC-link current ripples, the switching sequence of the conventional space vector pulse width modulation (SVPWM) method is replaced with the proposed switching sequence. By applying the proposed method, the DC-link current ripples are reduced substantially. The effectiveness of the proposed method was verified by simulation results.
ACKNOWLEDGMENT This work was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea (No. 20171210201100, No.20182410105160).
