Composite fault diagnosis method for diesel engine and diagnosis system

Abstract

The invention discloses a composite fault diagnosis method for a diesel engine and a diagnosis system. The fault of a fuel supply system of the diesel engine can be diagnosed based on comprehensive analysis of fuel flow monitoring, exhaust emissions, temperature detection and the like in the state parameter measuring method. In vibration analysis, vibrating signals are measured by a vibration acceleration sensor, noise is removed via empirical mode decomposition (EMD), and then characteristic parameters of the vibration signal acceleration are extracted in a manifold learning method. For failure of a piston cylinder, vibration analysis and fuel analysis are combined, and the degrees of friction and wear are judged according to the vibration amplitude and the content of Fe. The composite fault diagnosis of the diesel engine can be realized based on integration of the fault characteristic information and comparison with typical failure characteristics. The diesel engine fault diagnosis system is developed on the basis of integration of information of multiple characteristics, all characteristic information is fully utilized, the speed and accuracy of diagnosis can be improved, the advantages can be complemented, and the level of diesel engine fault diagnosis can be improved.

Description

Technical field [0001] The invention relates to the technical field of diesel engine fault diagnosis, in particular to a diesel engine compound fault diagnosis method and diagnosis system. Background technique [0002] At present, the commonly used methods for diesel engine fault diagnosis include rotational speed measurement, vibration analysis and oil analysis. The speed measurement method is a diesel engine speed measurement method that installs a sensor on the connecting parts of the diesel engine to measure the diesel engine speed. Rotation speed is a manifestation of a state during the operation of a diesel engine. [0003] Vibration analysis is to collect, record and analyze the vibration time-frequency domain signal changes of the vibrating parts in the diesel engine by applying various dynamic test instruments. Vibration signal processing mainly includes time domain analysis, frequency domain analysis and time-frequency domain analysis. The oil analysis technology mainl...

AI Technical Summary

Problems solved by technology

However, the detection methods of these technologies are relatively simple, and they do not deal with vibration and noise and do not reflect the degree of wear of friction pairs. The detection cycle is long and the accuracy of fault detection is not ideal.

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