Application of Wavelet Transform in the field of Electromagnetic Compatibility and power quality of industrial systems

In this paper, we present the theory behind the wavelet transformation (WT) and its applications in the field of electromagnetic compatibility. This transformation will allow the exploration of both frequency and time characteristics of a given signal at the same time, overcoming the limitations of the Fourier transform. We examine the application of wavelets in the treatment of perturbations affecting the quality of the power signal of the electric distribution systems (voltage dips, high voltage, harmonic dispersion..). The method was developed by using the MATLAB toolbox for discrete wavelet transform (DWT) analysis. The examples will be treated by both the STFT and the DWT. A comparison of the results will be presented. Finally, an application example of the DWT will be presented in order to characterize an internal fault in the transmission lines.