Prioritization of Transmission Projects in Power System Planning

Planning the expansion of electric power systems, particularly the transmission system, represents a dynamic and continuous process that requires constant adaptation to the changes that the systems experiment in their environment, whether they are economic, social or technical. Considering that the economic factor is one of the most conditioning aspects in any expansion plan, together with the dynamics of the electricity markets, it is evident that planners face the growing challenge of optimizing the available financial resources, so that any investment decision made in the electricity system is carried out after seeking the maximum possible benefits in technical, social, environmental and even political aspects. In Paraguay, the National Electricity Administration, through its Transmission Master Plan (PMT) for the period 2021-2030, has presented a strategic set of projected works in the 220 and $500\text{kV}$ transmission corridors, mainly with the objective of accompanying the marked growth in demand in recent years. In this paper, a methodology for the analysis and prioritization of transmission works is proposed, applied to a set of nine selected works of the PMT, based on the use of probabilistic indexes applied to the evaluation of the impact of these expansion projects on the reliability of the system during $\mathrm{N} - 1$ contingencies. The methodology is applied to equivalent models of the Paraguayan National Interconnected System and focuses on the impact on reliability at the end of the mentioned period, specifically for the years 2029 and 2030, in order to compare the impact on reliability of the works under study. Then, a prioritization tool is applied according to certain criteria, in order to finally determine the priority works of the set of works analyzed. In this way, the methodology presented becomes a useful tool when deciding on investments among a set of transmission works.