Distributed Generation Impact on Distribution Networks: a Review

The concept of traditional distribution networks with unidirectional power flow is weakening due to large penetration of Distributed Generation (DG). The penetration of DG may impact the operation of a distribution network in both beneficial and detrimental ways. Some of the positive impacts of DG are voltage support, power loss reduction, support of ancillary services and improved reliability, whereas negative ones include protection coordination, dynamic stability and islanding. Therefore, proper planning methods that evaluate the composite impacts, i.e. technical, economical and environmental impacts of DG integration to existing distribution networks are very much essential. This paper presents a critical review of various impacts of DG on power distribution system. For ease of reference and to facilitate better understanding this literature is categorized and discussed under five major headings.