Impacts of distributed generation on the coordination of protective devices in distribution network

The problems of selectivity and coordination of protection devices is one of the concerns related to the effects of the insertion of distributed sources. Those problems directly affect the safety of equipment and personnel and continuity of service. Analysis should be done to determine if the protective devices installed on the network are properly coordinated after inserting distributed sources. In the paper, the effects of the insertion of distributed sources in an electrical distribution system were evaluated and analyzed. A network with three distributed sources namely induction machine, wind turbine generator and synchronous machine was studied. Short circuit was performed on the different buses of the distribution network to determine its impacts on the short circuit currents and its detection time. The results show an increase in short circuit current on the nearest bus of the load (bus 3), while the detection time remains constant over the latter, but variable on the other two. These results are quite similar for the three studied cases and confirm perfectly those found in the literature.