Development of Electrolytic Capacitor Less Photovoltaic Grid Connected Inverter with Boost‐Up Type Active Buffer Circuit

Abstract

SUMMARYThis paper proposes a configuration of a single-phase voltage source inverter that features power decoupling capability. Generally, the converter connected to a singlephase grid employs bulky dc link capacitors such as electrolytic capacitors in order to decouple the power ripple with twice the frequency of the power supply. The power ripple in the proposed circuit is compensated by an active buffer with small capacitors. In this paper, the fundamental operations of the proposed converter are confirmed by experimental results. From the experimental results, the output current total harmonic distortion (THD) is 3.51%, the ratio of the input current is 14.3%, and the output power factor is over 99%. In addition, the volume of the proposed circuit is reduced by 61% when the carrier frequency is 64 kHz compared to that with a carrier frequency of 16 kHz. Finally, from an evaluation of the power density using Pareto front curves, the proposed circuit achieves high power density in comparison with the conventional circuit. C⃝ 2016 Wiley Periodicals, Inc. Electr Eng Jpn, 196(3): 39-48, 2016; Published online in Wiley Online Library (wileyonlinelibrary.com).