Narrow-band interference suppression method for partial discharge of power transformer based on Hankel matrix and singular value decomposition

A narrowband interference suppression method based on Hankel matrix and singular value decomposition (SVD) is proposed to address the issue that partial discharge (PD) signals of power transformer are prone to narrowband interference. Firstly, a Hankel matrix is constructed to elevate the original PD signal to a two-dimensional matrix space for SVD. Study the singular value patterns of narrowband interference, partial discharge signals, white noise, and the combined signals of the three. Then, determine the singular value order corresponding to the narrowband interference based on the singular value difference spectrum, complete the reconstruction of the narrowband interference signal, and finally subtract the reconstructed signal from the original signal to achieve the suppression of narrowband interference. Conduct narrowband interference suppression on the simulated noisy partial discharge signals in MATLAB, and perform a comparative analysis with the suppression results of the FFT threshold method. The simulation results show that this algorithm has advantages in terms of signal-to-noise ratio and root mean square error in suppressing narrowband interference.