回転機械の振動音響診断技術 : ウェーブレット変換による回転機械の故障診断

抄録

The wavelet transform is used to represent all possible types of transients in vibration signals generated by faults in a rotational machine. First, the selection of the wavelet parameters is discussed, and it is shown that the transform provides a highly sensitive tool for fault diagnosis when the most suitable parameter sets are selected. Second, a numerically generated fault signal is used to calculate the time-frequency distribution of the wavelets. Features contained in the time-frequency distribution are classified according to fault type. From this classification, by extracting the features of actual abnormal vibration signals, the cause of the fault can be deduced. The fault diagnosis method is implemented in a fault diagnosis system for pump vibration sounds. The results suggest the developed method provides a powerful tool for early detection of contact between the rotor and the stationary units.