Study on the frequency band energy distribution of pipeline broken wire signal based on φ-OTDR system

In order to better monitor and identify PCCP pipeline wire broken and obtain wire broken signal characteristics, this paper adopts φ-OTDR system to monitor pipeline wire broken signal and use wavelet packet decomposition to study the energy distribution of wire broken signal in different frequency bands. Firstly, the wire broken signal is collected by φ-OTDR system, and secondly, the wavelet packet decomposition is performed on the wire broken signal collected by the system to obtain the energy distribution of the wire broken vibration signal in different frequency bands. The results show that at 10kHz sampling rate, the frequency band energy (FBE) distribution of the wire broken signal is characterized as follows: the energy of the broken wire signal is higher in the high frequency band (2500-3125Hz, 3437.5-3750Hz, 4375-4687.5Hz) and lower in the low frequency range, and this feature is obvious compared with the non-broken wire case. This method provides a new idea for identifying wire broken events.