Estudo Comparativo de Técnicas Utilizadas na Detecção de Faltas em Linhas de Transmissão pela Abordagem Baseada na Análise Espectral do Sinal
Keywords: Short Time Fourier Transform, Wavelet Transform, Hilbert-Huang transform, Spectrogram, Fault current, Fault Detection
AbstractThis article presents the result of the comparison between three techniques used to detect the travelling wave signal for power lines fault location. The methods have in common the identification of the dominant frequencies of the traveling waves at the transmission line terminals as the transients propagate along the line. Among the three signal processing techniques considered, two are more traditional, the Short Time Fourier Transform (STFT) and the Wavelet Transform (WT). The third technique is the Hilbert-Huang Transform (THH), a new approach based on an elaborate adaptive method used for data analysis of non-linear and non-stationary processes. The three techniques have in common the spectrogram whose analysis provides signal parameters, among them, the instant of arrival of the traveling wave at the measuring terminal at the end of the line. The result of the comparison shows that the Hilbert-Huang Transform can accurately extract the arrival time of the traveling wave.