Análise de padrões PRPD utilizando transformadores de corrente de alta frequência

Abstract

The use of High-Frequency Current Transformers (HFCT) has emerged as a less invasive alternative for partial discharge measurements in high-voltage equipment. In this work, the feasibility of this technique in predictive maintenance applications was evaluated through the analysis of Phase-Resolved Partial Discharge (PRPD) diagrams. For this purpose, experimental signals from different test setups were processed using Digital Signal Processing techniques, including high-pass pre-filtering and Wavelet Transform-based filtering, with the calculated Signal-to-Noise Ratio (SNR) ranging from 9.14 dB to 15.83 dB. After processing, amplitude and phase parameters were used to construct PRPD diagrams in Python. The patterns obtained with HFCT were compared to the results of the conventional electrical method standardized by IEC 60270, showing consistent behavior with the specialized literature for identifying different types of faults. The results demonstrate the potential of HFCT sensors as a non-invasive monitoring and diagnostic tool for partial discharges in high-voltage systems.