  The proposed method introduces a parameter determination approach based on
the minimum Fractal box dimension (FBD) of Variational Mode Decomposition (VMD)
components, aiming to address the issue of manual determination of VMD
decomposition layers in advance. Initially, VMD is applied to the original
power signal, and the layer number for VMD decomposition is determined by
selecting the K value associated with the smallest fractal box dimension among
its components. Subsequently, several Intrinsic Mode Functions (IMFs) are
obtained as fundamental, harmonic, and interharmonic signals representing
different aspects of the power system. Furthermore, Hilbert transform(HT) is
employed to extract instantaneous amplitude and frequency information from
these harmonic signals. Experimental evaluation using simulation data and
real-world power system data demonstrates that compared to Empirical Mode
Decomposition (EMD) and Ensemble Empirical Mode Decomposition (EEMD), our
proposed method achieves more accurate identification and effective extraction
of harmonic signals.
