Integration issues of distributed generators considering faults in electrical distribution networks

In the recent years there is a great interest in integration of distributed generation (DG) units at distribution level; this integration leads to planning as well as operational challenges. Some possibilities to handle grid planning issues are addressed in this paper. Effects on grid protection, fault current level, and voltage profile are investigated and described for different types of DG units; the classification of DG units is based on their terminal characteristics in terms of real and reactive power delivering capability. Different scenarios for mis-coordination problems caused by DG interconnection are discussed. The effect of the DG on the voltage profile of a distribution network is demonstrated and studied with and without network faults. The penetration level, location, and type of interconnected DGs are used as parameters in order to verify the effects of DG on these aspects. Some approaches to overcome the integration problems occurred are viewed. The mentioned issues are illustrated with the aid of MATLAB simulations on a test radial distribution network.