Abstract: For load rejection in a pumped storage power station, noise interference usually makes it difficult to extract pressure pulsation information accurately from pressure signals at its volute inlet. This paper presents a joint reduction method that combines the variational mode decomposition (VMD) and the complete ensemble empirical mode decomposition of adaptive noise (CEEMDAN). This method first decomposes a pressure signal using VMD and reconstructs its components based on mutual information (MI) to reduce the permutation entropy (PE). Then, it decomposes the reconstructed signal using CEEMDAN and superimposes the components, so as to obtain the modified pressure data sequence that features a permutation entropy close to that of the simulation signal. Engineering case studies show that our new processing method is quite accurate in decomposing pressure signals measured at the volute inlet, and its use of mutual information improves the accuracy of component reconstruction using correlation coefficients. The results would promote accurate extraction and analysis of pressure pulsation in future.

Key words: pumped storage power station, variational mode decomposition, complete ensemble empirical mode decomposition with adaptive noise, mutual information, permutation entropy