Research on aerospace generator rotating rectifier fault feature extraction technology based on improved HHT method

Abstract This paper presents an improved signal-processing method based on the Hilbert-Huang transform (HHT), which is applied to the fault feature extraction of the aerospace generator rotating rectifier (AGRR). Initially, the excitation current of the alternating-current (AC) exciter is utilised as measurable information for data collection. Subsequently, the HHT is processed with variational mode decomposition (VMD), followed by the improvement of the variational Hilbert-Huang transform (VHHT) using particle swarm optimisation (PSO) to determine the modal decomposition number and the secondary penalty factor. Finally, the proposed PSO-VHHT method is compared with several other signal processing-based feature extraction methods through both simulated and practical experiment data, and an analysis of the diagnostic performance of these methods is also conducted.