Conventional protection systems in distribution systems are capable of identifying low-impedance faults since such faults produce high fault current levels. But in a high impedance fault case protection schemes fail to detect a fault due to the fact that such faults do not generate enough fault current to operate conventional protection devices and fuses. This paper presents a novel algorithm for high impedance fault detection in medium voltage distribution systems. The proposed algorithm leverages multi-resolution analysis using discrete wavelet transform analysis for improved reliability and accuracy, extracting d5 coefficients at the transformer secondary terminal of all phases and the neutral, calculating their energies and integrating and calculating the average slope and comparing them to a threshold slope value in order to take the right decision for high impedance fault detection. The research explores the algorithm’s effectiveness through extensive testing using MATLAB/Simulink software, demonstrating its potential as a valuable tool for enhancing the reliability of medium voltage distribution systems.
Cite this article as: B. Makkawi and Ö. Usta, “High impedance fault detection in medium voltage distribution systems using wavelet transform,” Turk J Electr Power Energy Syst., 2024; 4(1), 40-49.