Hht-based voltage quality disturbance detection method

A Hilbert-Huang Transform based (HHT-based) voltage quality disturbance detection method, comprising:

• obtaining frequency spectrum information of an original voltage signal, and determining whether the original voltage signal is a closely spaced mode signal;
• based on the frequency spectrum information, performing a singular value decomposition on the original voltage signal and performing a reconstruction to obtain a reconstructed voltage signal with an interference signal removed;
• if the original voltage signal is the closely spaced mode signal, performing a frequency modulation on the reconstructed voltage signal to obtain a frequency-modulated signal;
• adding white noise to the reconstructed voltage signal or the frequency-modulated signal, and then performing an empirical mode decomposition;
• and
• performing a Hilbert transform on each of a plurality of intrinsic mode functions obtained by the empirical mode decomposition to obtain an amplitude and frequency information of a corresponding intrinsic mode function, and finishing a detection of voltage quality disturbance.