Published Oct 27, 2009

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Jesús María López-Lezama, MSc

Mauricio Granada-Echeverri, MSc

Luis Alfonso Gallego-Pareja, MSc



Reliability is a key aspect in power system design and planning. Maintaining a reliable power system is a very important issue for their design and operation. Under the new competitive framework of the electricity sector, power systems find ever more and more strained to operate near their limits. Under this new scenario, it is crucial for the system operator to use tools that facilitate an energy dispatch that minimizes possible power cuts. This paper presents a mathematical model to calculate an energy dispatch that considers security constraints (single contingencies in transmission lines and transformers). The model involves pool markets and fixed bilateral contracts. Traditional methodologies that include security constraints are usually based in multistage dispatch processes. In this case, we propose a single-stage model that avoids the economic inefficiencies which result when conventional multi-stage dispatch approaches are applied. The proposed model includes an AC representation of the transport system and allows calculating the cost overruns incurred in due to reliability restrictions. We found that complying with fixed bilateral contracts, when they go above certain levels, might lead to congestion problems in transmission lines.


Electric power systems-protection, energy marketsProtección de sistemas de energía eléctrica, mercados de energía

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How to Cite
López-Lezama, J. M., Granada-Echeverri, M., & Gallego-Pareja, L. A. (2009). AC model for the combined dispatch of bilateral contracts and energy pool considering security constraints. Ingenieria Y Universidad, 13(2). Retrieved from

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