Power quality analysis in off-grid power system

The energy independence, reliability and safety of running energy distribution system and using renewable resources are keywords of research in recent years. This research leads to development of autonomous active distribution grids with the specific requirements. The Power Quality problems can arise by using renewable sources in active distribution grids. Problems are caused by decreased short-circuit power of local renewable sources, stochastic supply of electric energy from renewable sources and operating of active distribution grid in autonomous mode without connection to the external distribution system. In case of these conditions, the mutual interference between sources and loads is relevant and parameters of quality of electric energy can be exceeded. The results from analysis of quality of electric energy in the particular active distribution grid (off-grid power system) are introduced within this paper.