Power system stability analysis with large penetration of distributed generation

Distributed generation (DG) technologies based on renewable sources have become popular due to environmental and economic reasons. The integration of DGs into grid may create problems like voltage control, transient stability, etc., with the increase in their penetration level. In this paper, the impact of DGs on power system transient stability is studied through transient stability indicators like rotor speed deviation, oscillation time, terminal voltage, etc. The impact of DGs that are directly connected to grid and those which are indirectly connected through electronic interface is investigated for different transient events such as line to ground fault, load switching, etc. It is seen that DGs have both negative and positive impacts on transient stability depending upon size and connection type of DGs and also on the type and location of transients.