The invention relates to the field of electrical measurement and testing, in particular to a fault monitoring method and
early warning system for a bottom loading and unloading crane
pipe, and the method comprises the steps: obtaining and preprocessing the current,
voltage and vibration sequence of a
servo motor, and obtaining a corresponding IMF component and an
energy spectrum; and in combination with historical normal operation data and to-be-monitored data, the importance degree of the IMF component is evaluated, and the
time domain anomaly degree is obtained based on the standard deviation of the sliding window variance and the DTW distance. Odd
harmonic information is extracted from the
energy spectrum, and the
time domain anomaly degree is combined to obtain the comprehensive anomaly degree. And obtaining a fault degree through weighted integration, and inputting the fault degree into a
control system to judge a fault. According to the method, the
energy spectrum difference of the IMF components, the first-order difference sequence difference and the time-
frequency domain abnormal degree are comprehensively analyzed, the operation state of the
servo motor is comprehensively evaluated, key fault
information loss and single
time domain feature monitoring limitation caused by
elimination of high
noise components in a traditional method are avoided, and the accuracy and sensitivity of fault monitoring are remarkably improved.