基于车用发动机振动信号的状态参数研究

Research on the Condition Parameters of Vehicle Engine Based on the Vibration Signals

利用分形的特征参数———关联维数来表征发动机振动信号的分形性质。对多组不同状态的振动序列运用相空间重构法进行处理, 计算出不同状态的关联维数, 并探讨了关联维数与运行状态之间的内在联系, 同时结合燃料敲缸系数、机械敲缸系数进一步判断发动机的运行状态, 及时发现运行状态中的异常变化。实验结果表明, 关联维数能定量评估发动机的状态演化, 敏感地反应发动机的运行状态。

The correlation dimension as one of the fractal feature parameters was used to denote the fractal property of the engine vibration signals. With the operation of the phase space reconstruction, respective correlation dimensions of a series of vibration signals obtained under different conditions were calculated to find the intrinsic relationship between the indicator and the operating condition. Meanwhile the other coefficients indicating the engine situation of combustion and friction were discussed to confirm the engine condition and effectively discover the abnormal situation during the running process. The experiment result shows that the correlation dimension is sensitive to the condition evolution and convenient for the identification of abnormal operating states.