A new model for outaging transmission lines in large electric networks

This paper presents a new method for calculating line currents for multiple line outages in large electric networks at extremely high computational speeds. An example is given showing that only one minute of computation time is needed to test 160 k N-3 line outage configurations for a large network. Resulting line overloads are shown to agree well with AC load flow. The new method: (1) calculates line currents and powers for any set of multiple line outages; (2) tests for system separation due to lines outaged; (3) tests for electrical remoteness of lines being outaged; and (4) updates real power line distribution factors used in linear programming and probabilistic models. The method is restricted to passive networks in which tapped transformers are near unity.