A transformada discreta de Fourier aplicada à proteção de barras

Abstract

The present study aims to implement a methodology for differential busbar protection based on the operational logic of the REB500 relay, manufactured from ABB. The objective is to evaluate the relay's response to internal and external faults on the busbar by simulating single-phase, two-phase, and three-phase faults, varying parameters such as location and angle of incidence of the fault. The simulations were carried out using the ATPDraw software, and the generated data was exported to MATLAB to calculate the fundamental component using the Discrete Fourier Transform. This enabled the calculation of operating and restraint currents, which are essential for analyzing the characteristic curves of the REB500 relay. Graphical analysis was conducted separately for each phase, demonstrating that the methodology accurately detected internal busbar faults while rejecting external faults. These results highlight the high selectivity and reliability of the employed methodology, confirming its effectiveness in bus differential protection.