Research On Electrical System Fault Diagnosis Method Of Civil Aviation Engine

Electrical system is an important part of the civil aviation engine which contains a variety of wires and electrical components such as actuators and sensors.Electrical system works in high temperature,high load and strong vibration condition,which is easily to be influenced by external environment and prone to failure.Failures of the electrical system could directly affect the performance of engine,and even could cause engine failure.In this condition,flight safety would be threatened.For the internal connection of electrical system complex,there would be interaction of the multi components.And there are lots of cross connect signals between electrical components and wires,which lead to the difficulty of electrical system fault diagnosis.Therefore,by analyzing the composition and characteristics of the electrical system,electrical system fault isolation algorithm,engine wire fault diagnosis algorithm and electrical components fault location algorithm are researched with which we can diagnose civil aviation engine electrical system faults.In this paper,mathematical model of a typical electrical system was established based on system identification method and engine test data by analyzing the components and connections of aero engine electrical system at first.Then,federated kalman filter algorithm was used to isolate the electrical system.So the fault can be located in the electrical system unit body which is composed of typical wire harness and electrical components.As to aero-engine wire,the mathematical model of a single wire was built at first which can be used to analyze the characteristic impedance of the wire fault.Then the fault diagnosis method of the aero-engine wire was researched.As to wires with network structure,the transmission process of a signal in the wire network was studied at first.Then,typical wire network models were built and the fault diagnosis method was researched.In order to locate faults to the inner part of the electrical system unit body,fault diagnosis method of electrical system components is reserched based on artificial immune system.The composition and working principle of a typical electrical components VBV is analyzed at first.Then,mathematical model of electrical components was built which is the basis of the fault diagnosis method.Variable radius detector negative selection algorithm was chosen as the method to diagnose the multiple faults of the electrical system components.At last,VBV faults are simulated with which fault diagnosis method of electrical system components based on artificial immune system can be verified.At last,aero engine experimental platform CS/BV WESTT,wire network fault diagnosis test system and gas turbine engine performance numerical simulation software GSP are separately used to verify the electrical system fault isolation algorithm,engine wire fault diagnosis algorithm and electrical components fault location algorithm.The verification results show the feasibility of the fault diagnosis method.Fault diagnosis of electric system of civil aviation engine is realized through electrical system fault isolation algorithm,engine wire fault diagnosis algorithm,and electrical components fault location algorithm.With this work,fault diagnosis efficiency of the civil aviation engine electrical system can be leveled up which means of great significance to guarantee the safety of engine.