Power system observability via optimization

•A procedure to determine the observability of a power system is developed from an optimization perspective.•It determines: the observable islands, the unobservable states, and the unobservable branches.•The proposed approach is based on the solution of a well-behaved integer linear optimization problem.•The 14-, 30-, 57-, 118-, and 300-bus IEEE systems and the 2383-bus Polish network are analyzed.•The proposed technique is more computationally efficient than other traditional numeric-based approaches.

The observability of the state of a power system given a set of redundant measurements is a relevant problem as it is a necessary step prior to state estimation, as well as an accurate estimate of the state is crucial to achieve a secure operation. In this paper, this problem is addressed through a novel approach: the solution of a well-behaved integer linear programming problem. Several realistic case studies including up to 2383 buses (Polish system) illustrate the computational efficiency of the method proposed. The obtained results are analyzed from a statistical perspective and compared with a traditional approach using the design of experiments and analysis of variance (ANOVA) methodologies.