Wind turbine DFIG stator/rotor open phase diagnosis using FFT and 3-D plot CWT

In wind energy systems, doubly-fed induction generators (DFIGs) are widely used because they can produce electricity efficiently and operate over a wide range of wind speeds. However, like all electromechanical systems, DFIGs are prone to failures, one of which is open phase failure. The main objective of this paper is to present new results in the DFIG diagnostic approach for identifying stator and rotor open-phase failures. The approach is based on steady-state stator current analysis, using Fast Fourier Transform (FFT) and wavelets transforms (Continuous Wavelet Transform (CWT) and Discrete Wavelet Transform (DWT)) analysis with 2-D and 3-D approaches respectively. The effectiveness of the wavelet transform is confirmed by exposing simulation results, which demonstrate its ability to effectively analyze signals across various scales and resolutions. These results highlight how the wavelet transform can overcome traditional limitations associated with other signal processing techniques, such as the inability to provide localized information in both time and frequency domains. This capability is particularly evident in the 3-D time-frequency plot, where the wavelet transform offers a detailed and intuitive representation of the current signal. By capturing transient features and variations in the signal, the wavelet transform allows for a more comprehensive understanding of its underlying characteristics. Consequently, this method proves invaluable in applications such as audio processing, image analysis, and biomedical signal interpretation, where precise localization of features is crucial for accurate analysis and interpretation.