Novel proposal for the analysis of technical losses in medium-voltage feeders from single-phase and three-phase load flow data

Abstract

This work proposes a novel methodology for acquiring real data for load flow studies applied to the estimation of technical losses in three-phase unbalanced networks with renewable energy sources. A load flow analysis comprising an equivalent single-phase network is presented using real data under balanced conditions. In order to perform a three-phase load flow, it is mandatory to obtain electrical data from the three-phase network. However, there are no methodologies available in the literature for this purpose so far. In this sense, data collected from the application of the introduced approach in simulation tests were used to determine the technical losses in real three-phase feeders. From the results obtained in the single-phase analysis, one can identify the branches with the highest losses. The study could also be used as a benchmark project for reducing the losses by up to 94 MW in the region of Sobral, Brazil. From the results obtained in the three-phase analysis, it is possible to reduce the load imbalance in the real feeders while allowing the connection of renewable sources, resulting in a reduction of 73.32% in the percent losses, corresponding to US$ 2,315.21/month. Therefore, the data confirm that the analysis of technical losses and border measurements leads to satisfactory results, whereas the proposed method becomes an effective tool for distinct studies of the electricity sector. This approach is more accurate than the typical single-phase methodology, since it takes into account the load imbalance and the penetration level of distributed generation. Analysis of Electrical Networks (ANAREDE) and Network Analysis and Planning Studies of Power Distribution Systems (INTERPLAN) software were used to validate the three-phase analysis.