Small Noise in Power System Dynamics and its Relation to Security Assessment

This work develops a new method of quantifying the security of a stable operating point in an electric power system with respect to small random variations in load demand. For a nonlinear model of the power system dynamics which includes a white noise disturbance in the loads, the expected exit time of trajectories of the system from a set approximating the deterministic region of attraction is calculated in the small noise limit. This expected exit time is proposed as a security measure.