Diseño de un esquema de protecciones para un transformador de poder de tres devanados con RELÉ SEL 387E, cumpliendo la norma IEEE C37.91, mediante simulación en ETAP e inyección de corriente secundaria

Abstract

This research focuses on the implementation and evaluation of a differential protection system for power transformers using the SEL-387E relay and tests performed with the OMICRON platform. The behavior of the transformer under different fault conditions, including overcurrent and differential faults, is analyzed to verify the effectiveness of the protection and its response time. Through simulations and laboratory tests, the activation times of the protection system were identified under different configurations. The results indicate that the differential protection operates efficiently, enabling the rapid detection of internal faults without causing unnecessary trips in the presence of external faults or magnetization currents. Additionally, it was observed that the proper coordination between differential and overcurrent protection enhances the system’s reliability and reduces the risk of transformer damage. The study also identified opportunities for improvement in trip setting configurations and the need to implement preventive maintenance strategies to optimize the performance of the protection system. Finally, recommendations are proposed to strengthen the safety and stability of the transformer within a substation, ensuring its proper operation under adverse conditions and guaranteeing the continuity of the power supply.