Islanding operations for the distribution systems with dispersed generation systems

The purpose of paper is to investigate the transient stability and operation feasibility of power islanding with different types of dispersed generations in distribution system. A distribution substation is selected for case study to simulate the system transient stability. The mathematical models of dispersed generation systems including exciters, governors of gas turbine and pitch controller of wind-driven induction generator are used in the simulation program. To know the influence of load characteristics on the transient response, three kinds of load models are applied in the computer simulation. The simulation analysis of transient stability is executed for unbalance distribution system with dispersed generations of gas turbines and wind-driven turbines with three operation scenarios after the distribution system has been disconnected from utility. Different load shedding schemes and output power control of dispersed generation are considered to maintain the stable operation of islanding power system.