Diesel Engine Fault Diagnosis Based On Multi-information Fusion

As the industrial and agricultural production，The diesel engine is the most importantpower machinery, maintaining is of profound significance to its good working performance.However, as the structure complexity, diversity of fault , and poor work environment of thediesel engine and other reasons, led to the fault diagnosis of diesel engine, the rate of errormissing reported and misdiagnosis and many other practical problems.To begin with, this paper introduces the research status of fault diagnosis on diesel engineand typical methods in both domestic and overseas. And the necessity of multi-sourceinformation fusion technology applied to diesel engine fault diagnosis .And also researchdeeply into diesel engine structure and failure mechanism, introduces some details ofinformation fusion methods, obtained the feasibility on application of information fusion infault diagnosis. Finally, it make the decision level fusion of engine fault diagnosis by usingvibration signal and instantaneous speed signalWith the basis theoretical analysis, we set up some common error such as oil spilled, oilinterrupted, oil supply angle, filter blockage, e.g. collection and extract the characteristicvalue of the vibration signal and the instantaneous speed signal. Through multiplecharacteristic value comparison, at last，using a vibration signal wavelet packet energyspectrum and a rotating speed signal time domain curve of peak valley difference as thecharacteristic value of fault diagnosisThe accuracy of fault diagnosis will have a significantly improved by combined the resultsof each measuring point. With advantage of instantaneous speed signals in the single-cylinderfault accurate positioning and show the single-cylinder fault results in a two-dimensional way.Diagnosis system has the advantages of simple structure, small amount of calculation, and is easy to realize the online diagnosis. And also bring us an idea that we should qualitation atfirst and then position when making diagnosis for complex system.