DC ripple detection methods for building photovoltaic storage integrated distribution systems

Multiple forms of ripple generation sources exist in the photovoltaic storage integrated DC distribution system of buildings. A DC ripple detection method based on whale algorithm (WOA) optimized variational modal decomposition (VMD) parameters and Hilbert transform (HT) is proposed therefore. Firstly, the sample entropy (SampEn) is used as the fitness function; secondly, the detection signal is decomposed into the intrinsic modal components (imf) by the optimized VMD algorithm; then, the Hilbert transform is performed. Secondly, the signal is decomposed into intrinsic modal components (imf) by the optimized variational modal decomposition algorithm; then, the Hilbert transform is performed to obtain the amplitude and frequency parameters of the DC ripple components; finally, the proposed method is used to compare with the empirical modal decomposition (EMD) algorithm and the VMD algorithm, and results show the proposed method has a higher detection performance compared with EMD and VMD.