Contingency-Constrained Unit Commitment With Intervening Time for System Adjustments

TL;DR

This paper develops a novel optimization approach for power system unit commitment under N-1-1 contingency criteria, incorporating intervening time for system adjustments, and demonstrates improved system robustness and cost efficiency.

Contribution

It introduces a new branch-and-cut algorithm with a temporally decomposed bilevel separation oracle for large-scale N-1-1 security-constrained unit commitment problems.

Findings

Enhanced system robustness with intervening time considerations

Significant cost reductions demonstrated in IEEE test systems

Effective solution methodology for large-scale contingency problems

Abstract

The N-1-1 contingency criterion considers the con- secutive loss of two components in a power system, with intervening time for system adjustments. In this paper, we consider the problem of optimizing generation unit commitment (UC) while ensuring N-1-1 security. Due to the coupling of time periods associated with consecutive component losses, the resulting problem is a very large-scale mixed-integer linear optimization model. For efficient solution, we introduce a novel branch-and-cut algorithm using a temporally decomposed bilevel separation oracle. The model and algorithm are assessed using multiple IEEE test systems, and a comprehensive analysis is performed to compare system performances across different contingency criteria. Computational results demonstrate the value of considering intervening time for system adjustments in terms of total cost and system robustness.