Power Quality Problems in Autonomous Photovoltaic System with Energy Storage

The paper describes a photovoltaic system (PVS) composed of a group of photovoltaic (PV) panels and presents the initial evaluation of power quality (PQ) in the low-power microgrid connected to these PV panels. This PVS is called solar tree and it is built as a research platform at our faculty to conduct teaching and research on renewable energy sources. The solar tree can operate in two modes: on-grid and off-grid (autonomous operation). An off-grid mode was analysed and experiments were carried out in order to determine the maximum power that can be delivered to the load connected to this autonomous photovoltaic system (APVS). Also, the various consumer's responses to a sudden load changes in this APVS were analysed. The experiments were carried out by using modern power quality monitoring devices and PQ of this single-phase APVS with energy storage is examined in terms of compatibility with the relevant international standards.