共查询到17条相似文献,搜索用时 78 毫秒
1.
2.
一类基于状态估计的非线性系统的智能故障诊断 总被引:6,自引:0,他引:6
针对一类含有建模误差的非线性系统,研究了基于状态估计的智能故障诊断方法.首先提出一种状态估计器设计方法;然后在进行状态估计的同时用RBF神经网络来逼近系统所发生的故障.故障估计器的输入为系统的状态估计,所估计出的故障既可用作故障容错控制,也可用作报警.根据微分同胚,将含有建模误差的非线性系统变换为易于分析的规范形式,并在此基础上分析了故障诊断系统的稳定性和鲁棒性.仿真例子证明了该方法的有效性. 相似文献
3.
4.
针对基于迭代学习的故障估计器方法,提出一种基于扩张状态观测器(ESO)思想的迭代学习算法,以提高虚拟故障的收敛速度。该算法将ESO的输出误差非线性反馈机制用于迭代学习过程,利用故障估计器当前输出残差的非线性函数修正下次迭代时的虚拟故障值。对所建立的故障估计器的收敛性进行理论分析,并在此基础上进行了仿真实验。仿真结果表明,所提出的算法具有良好的收敛速度和故障估计精度。 相似文献
5.
6.
8.
针对一类非线性系统,研究基于自适应观测器的故障估计问题.设计了保证诊断系统稳定的实现故障估计的自适应调节律, 并通过H∞跟踪性能,分析了调节律中的参数对故障估计精度的影响.数值仿真验证了该方法的有效性. 相似文献
9.
一种新的基于迭代学习的故障检测和估计算法 总被引:4,自引:0,他引:4
将迭代学习策略应用到故障诊断中,提出一种新的故障检测和估计算法.引入虚拟故障参数,采用基于PID的迭代学习策略调节其中的虚拟故障,使虚拟故障逼近系统中实际发生的故障,从而达到对系统故障诊断的目的.理论证明和仿真结果验证了新算法的可行性和有效性. 相似文献
10.
本文针对机理模型未知的非线性非仿射多入多出(multiple-input and multiple-output,MIMO)离散时间系统, 研究了系统同时存在未知时滞和迭代变化运行时间区间的预测迭代学习控制(predictive iterative learning control,PILC)问题. 首先利用未知时滞的上下界信息建立了一种新型的动态线性化(dynamic linearization,DL)模型, 理论分析表明该模型能够等价描述本文所考虑的存在未知时滞的未知非线性系统. 同时, 设计一种新的数据补偿机制用以处理由于系统运行时间区间迭代变化而引起的数据丢失问题. 基于所建立的DL模型和数据补偿机制, 设计了能够同时处理未知时滞和迭代变化运行时间区间的预测迭代学习控制方法. 通过严格的理论分析同时给出了建模误差和跟踪控制误差的收敛性质. 最后, 通过仿真进一步验证了所提方法的有效性. 相似文献
11.
《Computers & Electrical Engineering》2014,40(7):2273-2284
In this paper, a novel fault detection and identification (FDI) scheme for time-delay systems is presented. Different from the existing FDI design methods, the proposed approach utilizes fault tracking approximator (FTA) and iterative learning algorithm to obtain estimates of the fault functions. Performance of the FTA is rigorously analyzed by investigating its stability and fault tracking sensitivity properties in the presence of slowly developing or abrupt faults for state delayed dynamic systems. A novel feature of the FTA is that it can simultaneously detect and identify the shape and magnitude of the faults. Additionally, an extension to a class of nonlinear time-delay systems is made by using nonlinear control theories. Finally, the applicability and effectiveness of the proposed FDI scheme is illustrated by a practical industrial process. 相似文献
12.
Yanjun SHEN 《控制理论与应用(英文版)》2010,8(4):447-452
In this paper, by using the well-known high-gain observer design, an update law for the gain and an adaptive estimation of parameters, a new method of fault diagnosis for a class of nonlinear systems is presented. Without resort to any transformation for the parameters, the estimation errors of the states and the parameters are guaranteed to be globally exponentially convergent by a persistent excitation condition. Compared to the existing results, it can be applied to nonlinear systems with nonlinear terms admitting an incremental rate depending on the measured output. A case study further verifies the validity of the proposed research. 相似文献
13.
14.
Robust fault diagnosis for a class of nonlinear systems 总被引:1,自引:0,他引:1
Robust fault diagnosis based on adaptive observer is studied for a class of nonlinear systems up to output injection. Adaptive fault updating laws are designed to guarantee the stability of the diagnosis system. The upper bounds of the state estimation error and fault estimation error of the adaptive observer are given respectively and the effects of parameter in the adaptive updating laws on fault estimation accuracy are also discussed. Simulation example demonstrates the effectiveness of the proposed methods and the analysis results. 相似文献
15.
Robust fault diagnosis based on adaptive observer is studied for a class of nonlinear systems up to output injection. Adaptive fault updating laws are designed to guarantee the stability of the diagnosis system. The upper bounds of the state estimation error and fault estimation error of the adaptive observer are given respectively and the effects of parameter in the adaptive updating laws on fault estimation accuracy are also discussed. Simulation example demonstrates the effectiveness of the proposed methods and the analysis results. 相似文献
16.
混杂系统是近年来研究的热点,针对混杂系统故障诊断难题,在对混杂系统描述的基础上,给出了混杂系统状态估计及离散模态识别的强跟踪滤波器算法,并将该算法扩展到状态与参数的联合估计,最后利用修正的Bayes算法作出故障判决,实现了混杂系统的故障诊断。通过对两容水箱典型混杂系统故障诊断的仿真实验,验证了该方法的有效性。 相似文献
17.
文中对非线性系统的故障诊断方面问题给予了归纳总结,指出了基于数学模型方法,基于信号处理方法和基于知识的方法在实现非线性系统故障诊断的基本思想,并进一步指出了各各非线性系统故障诊断方法及可能的发展方向。 相似文献