Faults Diagnosis Based on Lyapunov Exponent and Phase Trajectory for a Generator Sets
Hou Rong-tao · Journal of Northeastern University · 2004
Based on chaos theory and the motional characteristics of non-linear dynamical systems, the fault diagnosis to a rotor of turbo-set generator was discussed. Three different running states of the generator rotor were studied in time series to determine the largest exponents from acquired time series, combining with the phase diagrams analyzed in the three states. The results showed that the largest exponents of time series obtained in the three different running states are different greatly form each other, with the types of the faults of the generator rotor thus revealed. The results were proved by the phase trajectories reconstructed with displacements and velocity shown by the time series data. It means that the largest exponent can be used as a quantified value to judge the motional characteristics of non-linear dynamical systems. So, a new and reliable method called as Lyapunov exponent-phase trajectory is proposed to diagnose and predict the faults of a turbo-generator set or other complex mechanisms.