Proposal of a Control Scheme for an Active Filter on PV Micro-Inverter Applications

This paper aims to present the development of a single-phase inverter with high efficiency and high power density to be applied on photovoltaic panel's applications. A DC active filter technique, which mitigates the low frequency ripple across the DC Link, is proposed. This way, there is a reduction in the stored energy in the DC link, which avoids the need for a very large capacitance, which implies a reduction in costs and in total volume of the capacitive bank. The inverter uses the unipolar modulation in order to reduce the reactive energy on the DC side while a double LC filter with a resonant control provides a low current harmonic content, high power factor as well as a low leakage current. The validation of this work is done through simulation and experimental results obtained from a 2kW prototype converter.