发动机故障诊断经验影响系数的定量化问题

本文提出了根据发动机故障样本建立故障方程的方法。发动机经验故障方程是不同于发动机小偏差方程的另一类故障方程,它为发动机故障诊断提供了一条简便易行的途径,并且使发动机故障诊断范围扩展到气路分析方法难以适应的场合。文中讨论了经验故障方程的建立方法及其在发动机故障诊断中的应用,给出了利用经验故障进行发动机故障诊断的实例。

Quantization of Empircal Influence Coefficient for Engine Fault Diagnosis

Engine diagnosis is a matter of resolving the engine fault equations y=Ax, which express the relationship between the measurements and a large set of possible but im- probable malfunctions.The engine fault equations are generally underdetermined and can be resolved by MCPM (main characteristic parameter model) as previously presented by the same authors.At present,the engine fault equations,known as small change equations,are based on the thermodynamic relationship describing engine component matching operation. This paper presents another kind of engine fault equations,which are based on engine fault samples and can be called empirical fault equations.The empirical fault equations are similar to fault equations obtained by single factor experiments,but engine fault samples are used instead of the results of special experiments.Unlike small change equations,erhpiriacal fault equations are easily obtained and are of great use in diagnosing such faults as are beyond the limits of small change equations.The method of developing empirical fault equations and their application peculiarities are discussed,and some practical examples of engine fault diagnosis are given in the paper.The results of fault diagnosis using empirical fault equations are satisfactory.