基于卡尔曼滤波器的航空发动机传感器故障诊断分析.docx

承诺书
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摘 要
航空发动机传感器故障可能导致控制系统的失效,建立传感器故障诊断隔离和重构系统有助于提高控制系统的可靠性,本文研究了基于卡尔曼滤波器的航空发动机传感器故障诊断技术。
首先针对发动机部件级模型建立状态变量模型,介绍了利用最小二乘分步拟合法建立发动机线性模型的方法,在状态变量模型(SVM)的基础上研究了发动机大偏差模型和离散域模型与连续域模型的等效转换问题。
然后建立了适合进行控制系统故障诊断的卡尔曼滤波方程,并设计了常值增益卡尔曼滤波器,通过仿真验证卡尔曼滤波器能够对输出参数进行有效跟踪并能消除一定噪声。
设计针对发动机传感器硬故障及软故障的故障诊断系统,并对故障信号进行隔离和重构, 通过仿真试验验证基于卡尔曼滤波器的故障诊断及容错系统,在诊断硬故障和软故障时均有良好效果。在单故障诊断的基础上,提出了传感器双重故障诊断系统算法,通过仿真验证改进后的系统对双故障的诊断效果,并总结了降低诊断系统误诊率和漏诊率的一些方法。
关键词:航空发动机,状态变量模型,卡尔曼滤波器,故障诊断,容错控制
ABSTRACT
Aero-engine sensor failure may result in failure of the control system. To improve the reliability of the control system, a fault monitoring system must be established. In this dissertation, the research on sensor fault diagnosis of the aero-engine based on the Kalman Filter has been conducted.
The state variable model for the engine has been built first using the least squares fitting method. Then the establishment of the large deviation model for the engine based on the SVM has been made and the problem of the transformation between the discrete domain model and the continuous domain model is solved.
Then, according to the theory of Kalman filtering for the fault diagnosis system, a bank of Kalman filters with constant gains is designed. The simulation results show that the proposed approach can meet the requirement that the output parameters can be well tracked.
The design of fault diagnosis system for both soft and hard sensor faults is made. On this basis, the isolation and modation of fault signal can be achieved. The simulation tests verify that this system can achieve the goal that the fault signal can be rapidly detected and timely isolated. Based on the single fault diagnosis system, a method for fault diagnosis with two-sensor-failure has been proposed and proved that it ha