Validação, análise e mitigação de falhas em linhas de transmissão de energia elétrica usando ferramentas de qualidade e confiabilidade

Abstract

Transmission lines (TL) are essential components of the electric power system due to their function of transmitting generation over short and long distances. Historical data from the Brazilian National Electric System Operator have shown that TL are the assets with the highest incidence of disturbances, as they are constantly exposed to hostile environments, adverse weather conditions, and factors that are difficult to control. Recurrent disturbances result in unplanned outages that directly affect system reliability and power supply quality, and incur financial penalties for transmission companies. The objective of this research is to identify and highlight the main failures that cause TL outages and to propose actions that can minimize or eliminate the risks of failures and their effects. For this purpose, the study was divided into three articles. The first article consists of a systematic literature review aimed at identifying and synthesizing existing scientific knowledge on the application of Attribute Agreement Analysis (AAA), Fault Tree Analysis (FTA), and Failure Modes and Effects Analysis (FMEA) in electric power systems. In the second article, AAA was applied, based on expert opinions and contributions from artificial intelligence (AI), as a validation tool for the causes of forced outages in TL. In the third article, probabilistic fault trees were developed to highlight the combinations of failures that may lead to undesirable TL outages. Based on the fault tree, an analysis of the causes and effects of each identified failure mode was performed, as well as their prioritization according to the associated risk, calculated based on severity, occurrence, and detection indices. Finally, actions were recommended to mitigate or eliminate the risks that may cause TL outages. The results showed that FTA and FMEA are widely studied and consolidated techniques in electric power systems, unlike AAA, which has been little explored in this context. The application of AAA to TL highlighted weaknesses in expert opinions due to divergent views and subjective interpretations, as well as an increase in the robustness of the analysis results due to the use of artificial intelligence. Through the application of FTA and FMEA, it was possible to verify that the main causes of transmission line outages are lightning strikes, wildfires, and strong winds; however, those that present the greatest risk to the operation of TL and the electric power system are outages caused by wildfires, strong winds, vegetation, and tower collapse. This research can directly contribute to the prioritization of preventive or corrective actions with greater impact on the prevention of unplanned TL outages, assisting transmission companies in resource management, increasing the reliability of transmission line operation and maintenance, and consequently improving the quality of power supply.