Signals of mechanical equipment faults in operation with obscure symptoms and weak features are always contaminated by stronger background noise. To solve the difficulty
a new method called adaptive redundant multiwavelet is proposed. Following Chui-Lian multiwavelet and two-scale similarity transforms
and taking the minimum envelope spectrum entropy as the optimization objective and genetic algorithms as the optimization tool
the redundant multiwavelet is adaptively constructed. Compared with the Fourier transform
Db6 scalar wavelet transform and CL3 multiwavelet transform
the applications to fault diagnosis rub-impact for a rolling element bearing of outer-race and a flue gas turbine unit of show the improved effectiveness of the proposed method.
HE Zhengjia, ZI Yanyang, CHEN Xuefeng, et al. Transform principle of inner product for fault diagnosis [J]. Journal of Vibration Engineering,2007,20(5):528-533.
WANG Xiaodong, ZI Yanyang, HE Zhengjia. Multiwavelet construction via an adaptive symmetric lifting scheme and its applications for rotating machinery fault diagnosis [J]. Measurement Science and Technology, 2009, 20(4):1-17.
BRADLEY A P. Shift-invariance in the discrete wavelet transform [C]∥Proceedings of the 7th International Conference on Digital Image Computing: Techniques and Applications. Sydney,Australia: The University of Queensland, 2003: 29-38.
STRELA V. Multi-wavelets: theory and application [D]. Cambridge, USA: Massachusetts Institute of Technology, 1996.
CHUI C K, LIAN J. A study of orthonormal multi-wavelets [J]. Applied Numerical Mathematics, 1996, 20(3):273-298.
LI Hongkun, ZHANG Zhixin, MA Xiaojiang, et al. Investigation on diesel engine fault diagnosis by using Hilbert spectrum entropy [J]. Journal of Dalian University of Technology, 2008, 48(2):220-224.