Impact of distributed generation on the protection of distribution networks

This paper is based on simulation studies carried out by VTT Processes and University of Vaasa. In these studies PSCAD/EMTDC transient simulation software has been applied. One of the key issues has been to verify that normal network protection schemes and settings are not adequate when there are distributed generation (DG) units connected to the network. The protection coordination between network protection and the protection of the distributed generation units has also been studied. The results will be used to focus further research and development of protection concepts on the essential areas.