Metrological Approach for Identifying Abnormalities and the Causes of Harmonics in Electrical Power Grids using Wavelets

Abstract. In this work, current and voltage time series are analyzed using the continuous wavelet transform (CWT). It is shown that, in contrast to a Fourier transform, a CWT enables the detection and analysis of transient and short-term disturbances in power grids. This is particularly important during the commissioning and maintenance of power systems. So-called Daubechies wavelets are used as purposes. In addition, the family of complex Gaussian wavelets also allows resonance mode analysis. This approach enables the real-time series of current and voltage to be transformed into a complex time series. This shows that wavelets can be used to make statements about the active power transit even in the case of short-term disturbances in the power grid. Finally, practical examples of the application of this method complete this work.