In layman's terms, Contingency Analysis (CA) is a "what if" scenario simulator that evaluates, provides and prioritizes the impacts on an electric power system when problems occur. A contingency is the loss or failure of a small part of the power system (e.g. a transmission line), or the loss/failure of individual equipment such as a generator or transformer. Contingency analysis is an application function that uses a simulated model of the power system, to:
• evaluate the effects, and
• calculate any overloads,
resulting from each contingency.
Contingency Analysis is essentially a "preview" analysis tool. It simulates and quantifies the results of problems that could occur in the power system in the immediate future.
CA is used as a study tool for the off-line analysis of contingency events, and as an on-line tool to show operators what would be the effects of future outages. This allows operators to be better prepared to react to outages by using pre-planned recovery scenarios.
Definition from EPRI Smart Grid repository.https://smartgrid.epri.com/UseCases/ContingencyAnalysis-Baseline.pdf