A single-phase current-source inverter with active power filter for grid-tied PV systems

Abstract

This work presents a new power decoupling technique for grid-tied current-source inverter (CSI), in grid-connected photovoltaic (PV) systems. Single-phase converters have low-frequency power ripple in the dc-link. The proposed topology is intended to reduce the low frequency power ripple by using an active power filter (APF) on the dc-link, based on a bidirectional buck-boost converter, which provides compensating voltage in a very simple but effective way. The advantages of this configuration are: a) dc-link ripple minimization, b) passive components size reduction, c) improvement of maximum power point tracking (MPPT) performance; and d) compatibility with full range of CSI modulation index (0~1).