Effect of small random perturbations on power systems dynamics and its reliability evaluation

The effect of small random perturbations on dynamic system modeling and its application to the reliability evaluation of a multimachine power system are studied. Small perturbations in the operational characteristic of transmission lines and system loads are regarded as inputs to the system model, and a reliability measure that is based on the mean first passage time of the system from its stability region is proposed. The effectiveness of the proposed reliability index in considering system dynamics and its sensitivity to the variation of different system parameters are studied. Several design criteria are examined to determine the effect of system configuration. Policies are introduced to determine the robustness of different planning alternatives in handling imminent outages. This technique does not set any restrictions as to how the buses are interconnected, and it can be implemented on a large-scale power system