Abstract：Rotor fault diagnosis of rotating machinery under variable speed conditions is a difficult problem in the field of fault diagnosis. To solve this problem, a method based on variational mode decomposition (VMD) with multiscale permutation entropy (MPE) and fuzzy c means clustering (FCM) was proposed (VMD_MPE-FCM). Firstly, the vibration signals of rotor were decomposed with VMD into a series of intrinsic mode functions (IMF). Then, the IMF which contains the most unbalance fault features was selected according to the phenomenon that the amplitude at the first harmonic (1×) increases sharply when the rotor unbalance fault occurs. Furthermore, MPE method was taken to quantify the selected IMF. Finally, the quantified values were put into FCM as the feature vectors to obtain the standard cluster center of each speed condition. Following this, the nearness between data to be identified and standard cluster center was calculated with a series of fuzzy nearness algorithms, so as to realize the identification and classification. The displacement signals of unbalanced rotor under variable-speed conditions were analyzed with VMD_MPE-FCM, results show that proposed method can extract unbalance fault features of rotor precisely and effectively, so as to diagnose the unbalance rotor fault under variable speed conditions accurately.
Key words: variable-speed conditions；unbalance rotor fault; variational mode decomposition (VMD); multi-scale permutation entropy (MPE); fuzzy c means (FCM); fault diagnosis
钟志贤，马李奕，蔡忠侯，段一戬，陈金华. 基于VMD_MPE和FCM聚类的变转速工况下转子不平衡故障诊断方法[J]. 振动与冲击, 2022, 41(14): 290-298.
ZHONG Zhixian， MA Liyi， CAI Zhonghou， DUAN Yijian， CHEN Jinhua. Method of rotor unbalance fault diagnosis under variable-speed conditions based on VMD_MPE and FCM clustering. JOURNAL OF VIBRATION AND SHOCK, 2022, 41(14): 290-298.
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