关键词: 汽轮发电机, 故障诊断, 混沌, Lyapunov指数, 相轨迹图

Abstract: Based on chaos theory and the motional characteristics of non-linear dynamical systems, the fault diagnosis for 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 Lyapunov exponents from acquired time series, combining with the phase trajectory diagrams analyzed in the three states. The results showed that the largest Lyapunov exponents of time series obtained in the three different running states were different greatly from 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 Lyapunov 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 Lyapunov exponent-phase trajectory is proposed to diagnose and predict the faults of a turbo-generator set or other complex mechanisms.