The analysis of stochastic resonance and bearing fault detection based on linear coupled bistable system under levy noise

摘要

In this paper, the stochastic resonance (SR) phenomenon of the linear coupled bistable system induced by Levy noise is analyzed. Meanwhile, the characteristics of Levy noise is also analyzed according to its probability density functions (PDFs) of different stability index alpha, symmetry parameter beta, scale parameter a and location index mu. The mean of signal-noise ratio increase (MSNRI) is regarded as an index to measure the SR phenomenon. Then, the rules for MSNRI affected by noise intensity D are explored under different charastic indexes of Levy noise, system parameters a, b, c and coupling coefficient r. The results are beneficial to the numerical simulation of single-frequency and multi-frequency weak signals detection based on single bistable system and linear coupled system respectively. It is found that the performance of the proposed system is better than single bistable system and results of bearing fault detection could also verify the conclusion.