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The present work is a brief study on one of the proven electromagnetic phenomena of electric power transmission lines: the Audible Noise (AN) due to the corona effect. Through the equations available for the lateral profile of audible wheel in front of routines elaborated in the MATLAB® platform, where four case studies were carried out with a purpose of verifying a variety of RA in each of them and this variation of analysis varying some factors that were: the line voltage level, the number of subconductors per phase and the diameter of the conductors. Still no case study, and as a work differential, we have an analysis with 69 kV lines. The AN limits and requirements are established in Brazil by ANEEL Agency. These limits and requirements whose purpose is to assign responsibilities and establish the minimum requirements for airborne transmission lines that are part of the basic network. The studies performed represent a confirmation of concepts related to the generation of RA and also explains why the calculation for the 69 kV lines is unnecessary.

This research aims to evaluate the efficiency of thermography as a tool for the detection of faults in low voltage electrical networks. For this, a thermovisor was used in several equipment, such as panels, transformers and capacitor banks, to locate possible thermal anomalies. Two analyzes were made: one qualitative and the other quantitative. The first is based on the investigation between an adjacent element and the suspicious element and a definition of criticality, in which actions are taken to correct failures. The quantitative analysis aims at improving a definition of criticality where possible, such as not identifying the thermal emissivity of the materials involved that are not identified by the electric currents of the circuits. In addition, for the cases studied, a criticality comparison was made between the two methods.

The present work proposes to evaluate the contribution of the insertion of photovoltaic solar generation in the power quality in a distribution network in Marechal Deodoro-AL. The simulations were performed through the ATPDraw (Alternative Transient Program) software. These simulations were in situations of overload, considering the system in maximum imbalance allowed by PRODIST (Distribution Procedures) and in permanent regime. The currents of the photovoltaic solar generators have a unit power factor, and they even inject about 320 A in one of the buses of the feeder segment. The results obtained through graphs show that with the insertion of photovoltaic systems in the network there is a contribution of up to 2% in the voltage level, in case of overload, contributing in the quality of energy to the consumer.

In this work is presented in a simulated environment, the analysis of the required length of conterpoise cable connected to the ground rod in a transmission line located in Maceio, Brazil, capable of avoiding the phenomenon known as back flashover, in other words, the disruptive discharges of return in the chain of insulators when subjected to standardized atmospheric discharges considering some values of soil resistivity and some types of arrangement of geometric arrangements of grounding systems.

Polymeric insulators used in 13.8 kV distribution network are presenting premature damage due to cavity inner dielectric. With the objective to develop a diagnostic process, it was constructed an experimental distribution line in Universidade Federal de Pernambuco (UFPE) campus. In this article it will be described this experimental line characteristics and performed studies to plan its construction.