Mohammad Mehdi Saeednia - Department of Electrical & Computer Engineering, Babol university of TechnologyIran
Hadi Ezoji - Department of Electrical & Computer Engineering, Babol university of TechnologyIran

Application of distributed generation (DG) to supply the demand of a diverse customer base has been gaining popularity. Various DG technologies are being integrated into power systems to provide alternatives to energy sources or to improve reliability. The paper aims at providing an overview of the impact that distributed generation might have on the operation of distributed network. Issues like impact of DG on losses, voltage control, power quality, short circuit power, reliability, insulation and system protection are discussed. Based on the discussion, it can be concluded that the impact of DG depends on the penetration level of DG in the distribution network as well as on the DG technology. Furthermore critical issues, for example the impact of DG on the protection system, can be solved by using the right technology. technologies include photo voltaics, wind turbines, fuel cells, micro turbines, gas turbines and internal combustion engines. Cost of transmission and distribution is rising, but the costs of DG technologies are falling. This makes it more economical to meet an increase of load by connecting DG to distribution feeders rather than expanding transmission and distribution (T&D) facilities [2]. Therefore, these technologies are entering a period of rapid expansion and commercialization and studies have predicted that DG may account up to 20% of all new generation going on line by year 2010 [1]. Distributed generation is gaining more and more attention world wide as an alternative generation source. This paper therefore aims at discussing the relevant aspects related to DG and impact ondistribution network operation.

Distributed Generation, Distribution System, Voltage Control, Power Quality,Reliability, Protection