In the last two decades, the Brazilian power sector has undergone a major transformation, instituting more thorough processes for the licensing and construction of new transmission lines, stricter standards for electromagnetic (EM) fields in the vicinity of these lines, and harsher regulatory penalties for unscheduled power outages. This article describes concepts that are being applied in Brazil in the design and construction of new transmission projects, which have resulted from continued research that Centro de Pesquisas de Energia El?trica (CEPEL) has been conducting for decades on the measurement, monitoring, and uprating of transmission lines.

In this work, the main goal is to make a comparative analysis between conventional transmission lines and optimized lines known as HSIL (High Surge Impedance Line). For this analysis, computer programs were developed to calculate the line parameters and the electrical characteristics of the transmission lines in analysis. Additionally, the concept of geometric configuration optimization was explained through the application of a optimization program, where the obtained optimized bundles increase the transmission capacity. The conventional lines were compared with the optimized lines, the differences in their parameters are discussed, and the main characteristics are highlighted. At the end, electromagnetic transient simulations of the two selected transmission lines are presented using the software ATP.

The paper discusses the modeling of substations for reliability, dealing with each equipment and its influence in the topology. The study consider the power availability for each load, using either an analytic and a simulation model. Some results and a software implementation are presented.

This paper proposes comparative studies, analyzing how the voltages are developed when transmission lines have their lightning rods hit by atmospheric discharges, considering an analytical model and a software that simulates electromagnetic transients, ATP. The study was made using a 500 kV transmission line with compact profile (“cross-rope” design), after being made the required adaptations to ATP, and acquired the necessary data to conclude if the analytical model presents practical validity. The results contains the compilation of the overvalues of voltages, considering two scenarios, a strike near the tower and in the guard wires, near midspan. The results are presented, showing how the voltages acquired by the analytical model behave, and tables containing the critical currents calculated by the analytical model, which values if exceeded by the atmospheric discharge, according to the studies responsible for the development of the analytical model, can result in short-circuit.