Identification of critical lines for power system operational reliability assessment

Operational reliability includes the quantification of how near an operating point (or potential future operating point) is to feasible operational boundaries. Identifying this boundary or collapse region quickly and accurately remains a major challenge, as it is constantly changing, especially as the system grows in size and complexity. By combining direct measurements and necessary conditions of the system, two methods have been developed to estimate the system location and boundary: a static collapse detection and a linear solution failure detection.;The goal of power systems is to deliver power from point A to point B effectively and reliably. Identifying the stressed or critical line or lines to ensure successful power transmission is crucial. Three critical line identification methods are developed. One method is based on large-scale sensitivity analysis when a line outage becomes unsolvable. The other two methods try to quickly identify critical lines with only measurable parameters.