The Research On Location Method Of Submarine Cable Fault

Submarine cables are used in some of the more important occasions,such as crossing the river port,connecting the land and islands,connecting the drilling platform with each other,as well as military facilities across the sea.With the rapid development of marine economy,energy needed for the island is increasing,more and more offshore oil platforms has been constructed,submarine cables get a lot of use,while also increasing submarine cable fault.Typically,submarine cables laid in the seabed 1 to 2 meters deep.When a failure occurs,firstly,the trouble spot must be located,then the fault cable will be salvaged from the sea by a professional cable salvage ship,it willed be either repaired or replaced.Finally,the cable will laid on the seabed again and buried by stone and mud.It will takes several days or even decades to finish the work.It takes a lot of manpower and material resources and the cost is high.A deviation in the location will lead to the failure of salvaging and repairing work.The workers need to salvage and repair it again.Therefore,the accurate positioning of the fault point is essentialCurrently,due to the continued development of data filtering method and signal denoising method,while extracting means of various features of signals is more and more advanced,which gives birth to some submarine cable fault locating method which is more and more advanced and precision is higher and higher.These methods mostly use wavelet or multi wavelet filtering to process the signal and extract the feature,greatly reduces the difficulty of locating and improve accuracy.When the fault occurs,the fault recovery operation can be eliminated in the shortest time,which not only reduces the cost and time for the repairing but also reduce the economic loss of the country and the people,It has important practical significance for the normal operation of the equipment and the normal life of the people.The main contents of this paper are as follows three aspects.First,we come to a conclusion that the bridge method is not accurate enough for the fault location of the long cable by analyzing the relationship between the locating accuracy of the bridge method and the sensitivity of the components and the sensitivity of the instrument when the cable faults occurred under different length.Second,Stuying the fault locating method based on pulse attenuation rule.First step,a simulink model based on distributed parameter simulation platform cable has been constructed.then get reflected waveform signal pulse propagation in different cable lengths.Then extracted eigenvalues that can been used to characterize the reflective signal.Finally,the relationship between the eigenvalues and the propagation distance is established.Third,the input and output of the neural network are characterized by the eigenvalues and distance data and training for the neural networks,realizing the forecast function for distance.