Mathematical Models of Transmission Lines Applied to the Medium Voltage Electrical Network

The growing demand for supply of quality electrical power, together with the trends of distributed generation and the migration of electrical systems to Smart Grids, require the development of tests and computational simulations. The mathematical modeling of distribution systems, mainly of the electrical power Transmission Lines (TLs) makes this possible. In this context, this paper presents the mathematical modeling of a segment of the primary electrical power distribution network from real data. Initially, the data of a short TL of the primary distribution network of a utility company in the northwestern region of Rio Grande do Sul state (Brazil) are measured. Then, the TL mathematical modeling is performed, considering the implementation and simulation of PI, Bergeron, Modal (J. Marti) and Phase (Universal Line Model) models, in the PSCAD software. The simulation results allow the validation and comparative analysis of the models regarding the accuracy. It is observed that the equivalent circuit of the PI model represents accurately the network segment, then being considered as the more appropriate model for the output voltage prediction of a short medium voltage line. It requires fewer parameters and presents equivalent accuracy when compared to other models of electrical power TLs.