Research On Fault Diagnosis Of Ship Generator Set Based On Rough Set And Evidence Theory

In the context of big data,using ship operation data to diagnose ship equipment is an inevitable trend in the future.Ship generator sets are an important part of ships,which working in a harsh working environment,it is easy to cause equipment failure,and it is difficult to find out quickly,so accurate and rapid diagnosis of its fault is a hot topic of research.The structure of the ship generator set is complex,and the data generated during operation has certain redundancy and correlation.Therefore,the rough set theory is used to extract the fault feature data,and then the evidence theory is used to make the fusion decision of each feature data.This method not only can reduce the complexity of data,but also make full use of each data information to make the diagnosis result more reasonable and reliable.In this paper,the simulation model of the diesel engine and the excitation power unit of the generator part of the ship generator set are built first,and the operation data of the two simulation objects in each fault state are obtained respectively,The fault of each thyristor is simulated by excitation power unit simulation model,and obtains the data and waveform during the fault operation under each firing angle;when it comes to the diesel engine part,The simulation operation was carried out for five states of normal operation,fuel injection timing advance,fuel injection timing lag,fuel injection hole wear,and fuel injection hole clogging,and operation data was obtained.According to the data characteristics for the operation of ship generator sets,this paper proposes a fault diagnosis method based on rough set and evidence theory.Because the fault data has redundancy,the rough set theory is used to extract the important features of the fault data,and the basic credibility is calculated for the evidence theory.This method reduces the complexity of the data,and the basic credibility is objective.It avoids the defect of the subjectivity of basic credibility in evidence theory.The diagnosis results of fusion test based on evidence theory show that the fault diagnosis method based on rough set and evidence theory has higher accuracy,and the effectiveness of the method in fault diagnosis of ship generator set is fully verified.On the basis of theoretical research,in order to combine with practical application,Visual Studio 2013 and Matlab are used to jointly complete the fault diagnosis software of Marine generator set,which makes calculation more convenient and can display the operation process and diagnosis results intuitively.