A corrective frequency-constrained unit commitment with data-driven estimation of optimal UFLS in island power systems

M. Sarvarizadeh, L. Sigrist, A. Rouco, M. Rajabdorri, E. Lobato

International Journal of Electrical Power & Energy Systems Vol. 181, pp. 112154

Summary:

This paper presents a novel corrective frequency constrained unit commitment (FCUC) formulation for island power systems by implementing data-driven constraint learning to estimate the optimal under-frequency load shedding (UFLS). The Tobit model is presented to estimate the optimal amount of UFLS using the initial rate of change of frequency. The proposed formulation enables co-optimizing operation costs and UFLS. The aim is to account for optimal UFLS occurrences during operation planning, without increasing them. This would potentially reduce system operation costs by relaxing the reserve requirement constraint. The performance of the proposed formulation has been analyzed for a Spanish island power system through various simulations. Different daily demand profiles are analyzed to demonstrate the effectiveness of the proposed formulation. Additionally, a sensitivity analysis is conducted to demonstrate the effects of changing the cost associated with UFLS. The corrective FCUC is shown to be capable of reducing system operation costs without jeopardizing the quality of the frequency response in terms of UFLS occurrence.

Spanish layman's summary:

Este artículo propone un FCUC correctivo para sistemas insulares mediante un modelo Tobit que estima el deslastre óptimo de carga por baja frecuencia (UFLS). El modelo cooptimiza los costes de operación y el UFLS, manteniendo la calidad de la respuesta de frecuencia, y se valida en un sistema insular español.

English layman's summary:

This paper proposes a corrective frequency-constrained unit commitment (FCUC) for island systems using a Tobit-based approach to estimate optimal UFLS. The model co-optimizes operating costs and UFLS while maintaining frequency response quality and is validated on a Spanish island system.

 

Keywords: Frequency-constrained unit commitment; Data-driven; Tobit model; Frequency stability; Machine learning; Corrective

JCR-JIF Impact Factor and WoS quartile: 5,300 - Q1 (2025)

DOI reference: https://doi.org/10.1016/j.ijepes.2026.112154

Published on paper: August 2026.

Published on-line: September 2026.

Citation:
M. Sarvarizadeh, L. Sigrist, A. Rouco, M. Rajabdorri, E. Lobato, "A corrective frequency-constrained unit commitment with data-driven estimation of optimal UFLS in island power systems", International Journal of Electrical Power & Energy Systems, Vol. 181, pp. 112154, August 2026. [Online: September 2026] doi: 10.1016/j.ijepes.2026.112154