Contingency selection and static security enhancement in power systems using heuristics-based genetic algorithms

This paper proposes a technique to identify critical double-line outages and enhance static security by optimal placement of FACTS devices using heuristics-based genetic algorithm (GA). Two indices have been used for contingency screening: double-line contingency index (DCI), based on line overflows, and voltage sensitivity index (VSI), based on bus voltage violations. Contingency screening is treated as the primary optimization problem with an objective of finding all double-line outages with maximal DCI and VSI. Security enhancement is treated as a constrained secondary optimization problem. The objective is to reduce transmission losses through the branches of the system and reduce or remove the overflows and voltage violations present. The voltage magnitude at each bus and the line flow through each branch for all the buses and branches have been considered as inequality and equality constraints. The technique is demonstrated using IEEE 14 bus and IEEE 30 bus systems.