Review of power decoupling methods for micro-inverters used in PV systems

Abstract

In single-phase photovoltaic(PV) systems, power mismatch between input and output terminal leads to power pulsation, seriously affecting maximum power point tracking (MPPT). Paralleling an electrolytic capacitor(e-cap) across the PV panel to smooth power pulsation seems to be an unreliable method owing to its short lifespan. Various power decoupling methods used in micro-inverters have been proposed to solve the problem. These methods were categorized. Some of them were introduced in this paper regarding efficiency, cost and technical features. Special novel methods proposed in recent years were presented to show the development trend of micro-inverter. Then, conclusion and comparisons were made. Finally, a potential technological route was proposed by author for further study on power decoupling.