Research on wavelet transform of ultra-high harmonics in new energy grid connection

Aiming Considering the maturity of wavelet transform in the field of harmonic processing, aiming at the demand of interconnection of different new energy power generation equipment in the new energy grid-connected environment, this paper deeply studies eight kinds of wavelet transform at different levels, and compares them with traditional Fourier transform (FFT) and cosine discrete transform (DCT). In the research process, the experiment proves that when the level is 1, the wavelet transform of db1 wavelet basis function has the highest similarity between the original function and the reconstruction function, and the error variance is $6.5753 \times 10^{-28}$, which can better meet the needs of new energy grid connection. Therefore, this paper proposes that in the context of dealing with ultra-high harmonics, the 1-db1 wavelet basis function is the best choice for ultra-high harmonic processing of new energy grid-connected. This paper is devoted to providing a more suitable and efficient ultra-high harmonic processing algorithm for new energy grid-connected systems, and provides a useful practical reference for the selection of wavelet transform.