Applying adaptive protection scheme to mitigate the impact of distributed generator on existing distribution network

Abstract

Many studies indicate the importance of distributed generation (DG) as one of the best alternatives to conventional energy sources. The growth in population is causing a significant increase in electricity demand all over the world, which creating a considerable need for further investment in the electric network infrastructure. However, integration of new renewable energy source in the distribution network (DN) could impact the stability and the reliability of the distribution network if successful integration of renewable and distributed generation into the distribution network not achieved. Successful integration of distributed energy resources requires optimized control and planning for the network configuration which relies basically on the decentralized energy source management and protection system coordination. The aim of this study is to investigate the impact of utilizing DG on the performance of DN, especially on the over-current protective devices. Also, introducing a proposed adaptive protection scheme to mitigate the influence of DG penetration on the protection coordination by adding group setting, which exists in nowadays numerical protective relays, for different operating conditions such as islanding mode, and full MVA capacity of a DG. The simplified power system simulated in NEPLAN and ETAP packages represents Benghazi medium voltage distribution network. The simulation and results show the effectiveness of the proposed approach on the reliability and stability of the distribution network.