A Reliability Study of the Transmission Expansion Plan of Ecuador

Abstract

The objective of this article is to evaluate the reliability of the Ecuadorian National Interconnected System (acronym in Spanish SNI). It focuses on the sufficiency of the network and considers the projected changes in accordance with the proposals for the expansion of the transmission of the Electrification Master Plan for 2018 and 2025, under conditions of maximum demand. Two alternative methods were proposed for this analysis: the Exhaustive State Enumeration, and a Monte Carlo probabilistic simulation. As a decision parameter for the choice of one of these methodologies, we used the results of a preliminary test on the IEEE fourteen bus standard model, and determined that the best method for the evaluation of the national system was the Monte Carlo simulation. Using this method, our results demonstrated the reliability status of the SNI. The key theoretical elements for the quantification of reliability correspond to the reliability indexes, and we consider the energy index of reliability (EIR), the loss of load expected value (LOLE), the loss of load probability (LOLP), the expected power not supplied (EPNS), the expected energy not supplied (EENS), the frequency of interruption (FOI), and the duration of interruption (DOI). These data were obtained for the years 2018 and 2025, by analysing the transmission system and the composite level of transmission generation for a period of 20 years , with convergence criteria of 0.05%. Finally, the computational tool proposed within the development of this project helped determine that the plan of action exposed in the Electrification Master Plan does help to improve the reliability of the system between the years of study. However, based on the analysis of the very high numerical values seen in the reliability indexes, it should be noted that, although Ecuador is in the process of improving its electrical system, improvements will still be needed beyond 2025. This indicates that it is advisable to continue to conduct studies on the problems of the currently developing Ecuadorian system