Method for early recognition and prediction of unit damage or wear in machine plant, particularly mobile plant, based on vibration analysis with suppression of interference frequencies to improve the reliability of diagnosis

摘要

Method and device for monitoring machine plant based on vibration monitoring whereby the data is transformed into the frequency domain and back into the time domain to allow suppression of interference frequencies. According to the method structural noise of the machine plant is recorded using a sensor (1), transmitted as an acceleration signal and analyzed in a digital signal processor (DSP). To inhibit interference due to environmental vibrations or structural sound waves that do not relate to the status of the machine plant, the signal is transformed into the frequency domain using an FFT. It is then transformed back into the time domain using a cepstrum analysis such that single shock impulses (a cepstrum) are obtained in the time domain. The cepstrum is compared with a comparison value contained in memory that corresponds to load and speed signals for the current operating status. If the threshold is exceeded, conclusions can be made about damage to the unit and a remaining service life predicted. An emergency operation can be initiated.