Load curtailment strategy in distribution network with dispersed generations

Nowadays, large-scale penetration of dispersed generations (DGs) in the distribution systems has changed the structure of power system hence may create technical as well as safety problems. DGs have a large effect on real-time operation and planning for power systems by boosting the complicatedness of control, maintenance and protection of the distribution system network. Nevertheless, in the catastrophe following outage, the installation of DGs in the distribution system can provide local load reliability to be used during emergency and supply the required spinning reserve to maintain power system stability. However, the local voltage stability must be kept during emergency operation, therefore when voltage instability occurs in the distribution system, some load curtailments may be needed. Therefore this paper presents a new strategy of load curtailment in a distribution system with DGs. The proposed strategy is based on well-known static voltage stability approach; the modal analysis that involves eigenvalue and eigenvectors techniques. Numerical example on a 34-bus distribution network is given to illustrate the effectiveness of the proposed method. The analysis compare different load curtailment scheme with or without DGs.