8th IEEE Global Power, Energy and Communication Conference - IEEE GPECOM 2026, Naples (Italy). 03-05 June 2026
Summary:
Frequency nadir is one of the most informative indicators of post-contingency frequency security, but embedding it in frequency-constrained unit commitment (FCUC) remains challenging because nadir relations are nonlinear, non-convex, and are often introduced through computationally burdensome analytical approximations. This paper develops a scalable, opensource workflow for FCUC in which nadir security is enforced through calibrated affine surrogates learned from a secondorder differential equation (SODE) model while preserving unitcommitment mixed-integer linear programming (MILP) structure. The study employs Adaptive Latin Hypercube Sampling (A-LHS) to generate UC-relevant operating points, thereby avoiding exhaustive grid search, and are labelled using the opensource SODE model that captures dynamic effects neglected by simplified first-order formulations. Probability-calibrated linear surrogates are then embedded directly into UC through a common affine inequality, with conservatism controlled by an operator-selected probability threshold. The study focuses on the IEEE RTS-96 system under the largest contigency event of 400MW and positions this benchmark as an extension of our earlier smaller-system study to a materially larger test system. Results show that the analytical first-order formulation remains systematically optimistic against the SODE model. Also the SODE-trained surrogates show a much stronger security performance with modest cost impact and substantially lower computational burden.
Spanish layman's summary:
Este artículo utiliza modelos simplificados basados en datos para programar centrales de forma eficiente y mantener la frecuencia de la red dentro de límites seguros tras perturbaciones.
English layman's summary:
This paper uses simplified data-based models to schedule power plants efficiently while keeping the grid’s frequency within safe limits following unexpected disturbances.
Keywords: frequency-constrained unit commitment, frequency nadir, low-inertia systems, second-order differential equa tion, machine learning surrogate, IEEE RTS-96
DOI: 
https://doi.org/10.1109/GPECOM70462.2026.11578868
Published in: Proceedings of the 2026 IEEE 8th Global Power, Energy and Communication Conference: IEEE GPECOM 2026, pp: 703-708, ISBN: 979-8-3315-5205-3
Publication date: 02-Jul-2026.
Citation:
A.O. Olasoji, D.T.O. Oyedokun, M. Rajabdorri, J.E. Sierra-Aguilar, Ch.E. Okafor, M. Mditshwa, K.A. Folly, "Frequency-Constrained Unit Commitment Using SODE-Labelled Affine Surrogates", presented at 8th IEEE Global Power, Energy and Communication Conference - IEEE GPECOM 2026, Naples, Italy, 03-05 June 2026. In: Proceedings of the 2026 IEEE 8th Global Power, Energy and Communication Conference: IEEE GPECOM 2026, pp. 703-708, doi: 10.1109/GPECOM70462.2026.11578868
IIT-26-252C
