One of the major problems in transmission lines is the occurrence of failures that affect the quality of the electric power supplied, as the exact localization of the fault must be known for correction. In order to streamline the work of maintenance teams and standardize services, this paper proposes a method of locating faults in power transmission lines by analyzing the voltage oscillographic signals extracted at the line monitoring terminals. The developed method relates time series models obtained specifically for each failure pattern. The parameters of the autoregressive integrated moving average (ARIMA) model are estimated in order to adjust the voltage curves and calculate the distance from the initial fault localization to the terminals. Simulations of the failures are performed through the ATPDraw ${}^{\circledR }$ (5.5) software and the analyses were completed using the RStudio ${}^{\circledR }$ (1.0.143) software. The results obtained with respect to the failures, which did not involve earth return, were satisfactory when compared with widely used techniques in the literature, particularly when the fault distance became larger in relation to the beginning of the transmission line.

Fault location in electric power distribution networks is essential to improve the continuity and quality of the power supply. Among the fault location methods, those based on artificial intelligence are less sensitive to noise in the input data and considerably more accurate compared to other methods. However, these methods require a substantial amount of training data. Thus, this study proposes a method to automatically generate a fault database for faults in electric power distribution networks using ATPDraw/ATP software and the Python programming language. The IEEE34 bus system was used to validate the proposed method, resulting in a fault database, made available to the scientific community, with 6700 files containing different types of faults, incidence angles, and fault resistances.

This article aims to describe Brazil’s experience with Demand Response (DR) programs, focusing on their characteristics and benefits. DR programs have enormous potential to assist in meeting the growing demand for electrical energy, providing greater flexibility, efficiency and reliability to the electrical system. To better identify possible improvements that can be implemented in existing programs in Brazil, an overview of international experiences with these programs is presented.

This paper presents a study of alternatives for Photovoltaic Systems installations at electrical engineering Building - UFPI. Three types of systems are proposed a Grid-connected PV systems without battery, a Stand-Alone Photovoltaic System for Energy Backup and, a Grid-connected PV systems with battery or mixed Photovoltaic System, as result from combination of the two systems mentioned above. The sizing calculations and the savings generated in the monthly energy consumption of the building are presented for each of the proposals, approximately 45% for the Stand-Alone Photovoltaic System for Energy Backup, 61% for the Grid-connected PV systems without battery and, 80,52% for the mixed Photovoltaic System. Este artigo apresenta um estudo de alternativas de instalação de Sistemas Fotovoltaicos no bloco de Engenharia Elétrica da Universidade Federal do Piauí (UFPI). São propostos três tipos de Sistemas, um Sistema Fotovoltaico Conectado à Rede sem armazenamento de energia (SFCR), um Sistema Fotovoltaico Isolado para Backup de Energia e por fim um Sistema Fotovoltaico Conectado à Rede com armazenamento de energia ou Sistema Misto, resultado da combinação dos dois sistemas citados anteriormente. São apresentados os cálculos de dimensionamento, bem suas respectivas taxas de economia geradas, sendo de aproximadamente 45% para o Sistema Fotovoltaico Isolado para Backup de Energia, 61% para o Sistema Fotovoltaico conectado à Rede sem armazenamento de energia (SFCR), e de 80,52% para a configuração de Sistema Misto.