Testes e ensaios elétricos em subestações de média tensão

Abstract

Power substations are defined as a set of medium or high voltage electrical installations that integrate equipment, conductors and accessories, for the protection, measurement, maneuver and transformation of electrical quantities. Its proper operation requires the performance of tests and trials that indicate the need for maintenance, which in turn requires proper organization and knowledge of the equipment in a power substation. Thus, the objective of this study was to prepare a literature review on the main components of a medium voltage substation and the basic tests and trials to be performed in order to reduce the occurrence of failures and the need for corrective maintenance. The main equipment studied in substations up to 13.8 KV will be circuit breakers, disconnecting switches, instrument transformers, overcurrent protection relays, lightning arresters, insulators, bushings, the no-break battery bank and the grounding grid. Each of these pieces of equipment needs to be constantly submitted to tests and trials, such as the measurement of insulation contact resistance. It was found in this work that carrying out maintenance in electric power substations, especially predictive maintenance, is the main way to avoid operational failures and reduce costs, and that the maintenance of electric power substations should be carried out following a series of technical standards that ensure the safety of employees.