  Distributed Generation (DG) has emerged as best alternative to conventional
energy sources in recent times. Decentralization of power generation,
improvement in voltage profile and reduction of system losses are some of key
benefits of DG integration into the grid. However, introduction of DG changes
the radial nature of a distribution network (DN) and may affect both magnitude
and direction of fault currents. This phenomenon may have severe repercussions
for the reliability and safety of a DN including protection coordination
failure. This paper investigates the impact of DG on protection coordination of
a typical DN and proposes a scheme to restore the protection coordination in
presence of DG. Moreover, impact of different DG sizes and locations on DN's
voltage profile and losses has also been analyzed. The sample DN with embedded
DG is modelled in ETAP environment and the simulation results presented show
the effectiveness of the proposed protection strategy in restoring relay
coordination of the network in both isolated and DG connected modes of
operation.
