A tool for prioritizing distribution system equipment renewal plans based on multi-criteria analysis and estimation of remaining useful life

This work presents a tool developed to assist decision making for maintenance and replacement of assets based on the determination of priority equipment in a renovation plan. Different data sources and multi-criteria evaluation were used in an integrated way, focusing on individual distribution substation equipment. The necessary parameters were obtained from accounting, georeferencing and maintenance data for substation equipment, using well-established reports such as the Asset Control Report (ACR), Geographical Database of the Distribution Company (GDDC) and history of the maintenance system . With this information, it is possible to determine several essential parameters for controlling the life of equipment, such as depreciation of assets, replacement values, in addition to allowing the estimation of the remaining technical useful life with the application of machine learning techniques. When evaluating assets by different indicators, multi-criteria analysis is then used to determine a ranking of equipment priorities. In this case, the Analytic Hierarchy Process (AHP) method was used, where a pair-by-pair comparison of the parameters under analysis is performed, based on weights established by the planner. Thus, the criteria adopted for judging the equipment were: 1) accumulated depreciation; 2) economic benefit; 3) exchange cost; 4) shutdown impact; 5) DEC and FEC of the set and; 6) obsolescence level. Therefore, the tool presented in the work provides a detailed view of the individual situation of the distributor's main assets, making it possible to rank the assets based on the analysis of their criteria. The priority list can also be sorted by feeders, entire substations and regional maintenance, allowing you to identify where depreciation is highest and the correlation with the operating costs assigned to that region. Finally, the tool also makes it possible to establish a periodic renewal plan, as it allows for the monitoring of the main characteristics of the assets.