Chaotic Oscillator Detection Based on Empirical Mode Decomposition and Its Application

In order to accurately make out early fault diagnosis of rotor system with weak signal, a novel fault diagnosis method based on empirical mode decomposition(EMD) associated with chaos oscillator was presented. Weak periodic signals can be detected by identifying the transformation of the chaotic oscillator from the chaotic state to the large-scale periodic state when a weak external periodic signal is applied. As the actual signal is generally a mixture of signal and noise, and interested weak signal is usually submerged in strong background and noise signals. EMD is proposed to remove component interference, and actual signal is divided into finite intrinsic mode functions (IMFs), so that weak characteristic signal can be separated from background and noise signals, and a reliable and convenient measure for weak periodic signal detection by Duffing oscillator can be completed efficiently. Numerical simulation and experimental results show the validity of the presented method.