Data-driven design of monitoring and diagnosis systems for dynamic processes: A review of subspace technique based schemes and some recent results

In this paper, the development of data-driven design of process monitoring and fault diagnosis (PM-FD) systems is reviewed and some recent results are presented. A major objective of this work is to sketch a process input–output data based framework of designing PM-FD systems for dynamic processes. The main focus of our study is on the data-driven design of observer-based PM-FD systems, which are, thanks to their high robustness and real-time ability, suitable for industrial applications.     

一种鲁棒故障检测与分离的参数化方法

针对具有未知干扰输入的多变量线性系统,提出一种鲁棒故障检测与分离的完全参数化方法。利用最近的结果,基于Luenberger未知输入观测器矩阵的特征值及一组自由参数向量,分别给出了系统干扰解耦和故障分离的充要条件。通过适当选择满足一些约束的自由参数,仅使用单一观测器实现了鲁棒故障检测与分离设计。该方法提供了所有设计自由度。一个数值例子证明了该方法的有效性。     

On observer-based fault detection for nonlinear systems

This paper addresses analysis and integrated design of observer-based fault detection (FD) for nonlinear systems. To gain a deeper insight into the observer-based FD framework, definitions and existence conditions for nonlinear observer-based FD systems are studied first. Then, a scheme for an integrated design of observer-based FD systems for affine nonlinear systems is proposed. Our work is considerably inspired by the study on input–output stability and stabilization of nonlinear systems. Examples are given at the end of the paper to illustrate the theoretical results.     

Event-triggered simultaneous fault detection and tracking control for multi-agent systems

The main aim of this study is to design distributed simultaneous fault detection and control units for multi-agent systems subject to limited communication and energy resources. For this purpose, each agent is equipped with a single module that generates both the residual signal for the fault detection task, as well as the control input of each agent for the tracking objective. To reduce the communication among the agents, an event-triggered data transmission paradigm is considered by using a dynamic triggering rule which results in higher data transmission reduction in comparison with the static triggering condition. Moreover, the proposed dynamic observer-based structure for the detector-controller module provides more degrees of freedom compared to the static Luenberger observer. The design parameters are obtained by solving a multi-objective optimisation problem considering the fault detection, tracking, and communication objectives. Simulation results illustrate the effectiveness and capabilities of the proposed method.     

Robust fault detection filter design for networked control systems with delay distribution characterisation

In this article, robust fault detection (RFD) is investigated for networked control systems with delay distribution characterisation. By utilising an observer-based fault detection filter as a residual generator, the RFD of networked control systems with non-uniformly distributed network‐induced time-varying delay is formulated as an H _∞ model-matching problem. Delay-interval-dependent and delay-interval-occurrence-rate-dependent sufficient conditions are obtained by employing the Lyapunov–Krasovskii functional approach. Especially, the robust fault detection filters guarantee strong robustness from residual signal to disturbance as well as high sensitivity to faults. A numerical example is given to illustrate the effectiveness of the proposed design techniques.     

Observer-Based Fast Rate Fault Detection for a Class of Multirate Sampled-Data Systems

This note deals with the problem of observer-based fast rate fault detection for a class of multirate sampled-data (MSD) systems. Applying a lifting technique, a linear time-invariant (LTI) representation with slow sampling period is firstly obtained for the MSD systems and, based on this, an observer-based fault detection filter is considered as a residual generator. Then an optimization fault detection approach for LTI systems is modified to the residual generation for the MSD systems and, by solving a discrete-time Algebraic Riccati equation, a family of optimal solutions with causality constraint can be obtained. An inverse lifting operation on the generated residual implements its fast rate. The residual evaluation problem is also considered. A numerical example is finally given to illustrate the effectiveness of the proposed design techniques     

Subspace aided data-driven design of robust fault detection and isolation systems

This paper deals with subspace method aided data-driven design of robust fault detection and isolation systems. The basic idea is to identify a primary form of residual generators directly from test data and then make use of performance indices to make uniform the design of different type robust residuals. Four algorithms are proposed to design fault detection, isolation and identification residual generators. Each of them can achieve robustness to unknown inputs and sensitivity to sensor or actuator faults. Their existence conditions and multi-fault identification problem are briefly analyzed as well and the application of the method proposed is illustrated by a simulation study on the vehicle lateral dynamic system.     

A Model-free Approach to Fault Detection of Continuous-time Systems Based on Time Domain Data

In this paper, a model-free approach is presented to design an observer-based fault detection system of linear continuoustime systems based on input and output data in the time domain. The core of the approach is to directly identify parameters of the observer-based residual generator based on a numerically reliable data equation obtained by filtering and sampling the input and output signals.     

Models,residual design and limits to fault detection for a complex multi-tank hydraulic control system

System modelling, fault detection and control are considered for a general hydraulic n -tank system. A subsystem of n @ 2 tanks is situated in a remote, and possibly hazardous, environment and only control and measurements of the outer tanks are possible. The non-linearities in the system model are not particularly smooth. Given a set of non-linear differential equations, several transformations and smooth approximate input-output maps are derived to aid the establishment of equilibrium points and the design of controllers, observers and residuals for fault detection. A non-linear, high-gain, observer-based residual design is considered and developed for which error stability and detectability are examined. This design and a design based on a polynomial model are used to examine residual effectiveness as system complexity increases. For each design four systems are considered with n = 3, 6, 12, 24. Evidence shows that, for both designs, and for each fault position selected, the effectiveness of an observer-based residual is limited by system complexity. The limit is shown to be expressed in terms of a limiting line relating measurement error to n . The transformations, mappings, and the methodology involved are applicable to other hydraulic systems of similar non-linear structure.     

不确定奇异时滞系统的鲁棒H∞故障诊断滤波器设计

研究一类受参数不确定性和干扰影响的奇异时滞系统鲁棒故障诊断滤波器设计问题. 把基于观测器的故障诊断滤波器作为残差产生器, 将故障诊断滤波器设计归结为H∞滤波问题, 使产生的残差信号即为故障的H∞估计, 给出了鲁棒H∞故障诊断滤波器存在的充分条件, 并利用锥面互补线性化迭代算法得到了故障诊断滤波器设计的线性矩阵不等式求解方法. 算例验证了算法的有效性.     

Robust fault diagnosis for non-Gaussian stochastic systems based on the rational square-root approximation model

The task of robust fault detection and diagnosis of stochastic distribution control （SDC） systems with uncertainties is to use the measured input and the system output PDFs to still obtain possible faults information of the system. Using the rational square-root B-spline model to represent the dynamics between the output PDF and the input, in this paper, a robust nonlinear adaptive observer-based fault diagnosis algorithm is presented to diagnose the fault in the dynamic part of such systems with model uncertainties. When certain conditions are satisfied, the weight vector of the rational square-root B-spline model proves to be bounded. Conver- gency analysis is performed for the error dynamic system raised from robust fault detection and fault diagnosis phase. Computer simulations are given to demon- strate the effectiveness of the proposed algorithm.     

Model-free direct fault detection and classification

The present paper deals with the problem of fault detection and diagnosis in large scale engineering processes. These processes are typically equipped with database management systems and data logging servers whereby the measurement data is cleaned and stored. The expert knowledge of engineers and technicians as well as historical data records about abnormal scenarios experienced in the past is often available at hand. In this work we propose a framework where fault detection and classification can be done online directly on new data record without dimensionality reduction or any distributional assumptions. The proposed algorithm is based on a two-sample test via kernel mean embeddings of probability distributions. The Tennessee Eastman benchmark process is used to assess this new data-driven approach on different simulated faults.     

基于状态观测器的鲁棒故障诊断滤波器设计LMI方法

研究受不确定性扰动影响情况下线性时不变连续时间系统的鲁棒故障诊断滤波器设 计问题.引入一种新的体现残差对于故障信号灵敏度和不确定性扰动鲁棒性的性能指标,从系 统的L2增益角度出发,将基于状态观测器的鲁棒故障诊断滤波器设计问题形成为H∞优化问 题.然后应用线性矩阵不等式技术,给出并证明了该设计问题的解存在条件和求解方法.并通过 简例说明了算法的有效性.     

奇异Markov跳跃系统的鲁棒故障检测

研究受L2有界未知输入影响的一类奇异Markov跳跃系统的鲁棒故障检测问题。采用基于观测器的故障检测滤波器（FDF）作为残差产生器,将故障检测滤波器的设计归结为随机意义下的H∞滤波问题。推导并证明了问题可解的充分条件,并通过求解线性矩阵不等式得到了故障检测滤波器参数矩阵的解。算例验证了所给算法的有效性。     

具有多通道数据传输的飞行器网络控制系统故障检测

研究具有多通道数据传输的飞行器网络控制系统故障检测滤波器(FDF)设计问题.考虑每个通道存在各自的网络时延,且丢包符合Markov随机过程.首先,将系统建模为转移概率部分已知的离散Markov跳变线性系统,并设计了基于观测器的故障检测滤波器,将故障检测问题转化为H∞滤波问题;然后,利用LMI工具给出了FDF的可解条件和求解方法;最后,通过某飞行器网络控制系统的数值仿真实验验证了所提出方法的有效性.     

基于T-S 模糊模型的一类非线性网络控制系统故障检测

针对同时存在网络时延和数据包丢失的网络环境,研究了一类非线性网络控制系统的鲁棒故障检测问 题．基于不确定T-S 模糊模型描述的非线性网络控制系统模型,完成了网络环境下鲁棒故障检测观测器的设计,使 得残差信号对故障敏感而对外部扰动具有鲁棒性．构造Lyapunov-Krasovskii 函数,并引入一个积分不等式,给出了 使得观测器误差动态系统渐近稳定的充分条件．采用线性矩阵不等式技术将鲁棒故障检测问题转化为具有线性矩阵 不等式约束的凸优化问题求解．仿真算例验证了上述方法应用于此类系统的故障检测的有效性．     

一种新的时滞系统鲁棒故障诊断滤波器设计方法

研究具有扰动不确定的状态时滞系统鲁棒故障诊断滤波器的设计问题.通过对系统传递函数输入输出通道的组合变换,引入一种能够同时体现残差对扰动信号鲁棒性和对故障信号灵敏性的性能指标,将基于状态观测器的鲁棒故障诊断滤波器设计问题转化为H∞优化设计问题,应用线性矩阵不等式(LMI)技术,给出并证明了该设计问题解存在的条件和求解方法.最后,通过一个仿真算例来验证本方法的有效性.     

网络化切换控制系统故障检测与优化设计

研究存在未知短时延、丢包和系统不确定性的网络化切换控制系统故障检测与时域优化问题. 首先基 于观测器构建残差发生器, 结合Lyapunov 函数方法和平均驻留时间方法分析系统的稳定性, 并以线性矩阵不等式(LMI) 形式给出故障检测滤波器的求解方法; 然后为了改善故障检测系统的性能, 采用后置滤波器对残差信号进行时域优化, 并利用奇偶空间方法给出其最优解; 最后设计并推导出自适应阈值. 仿真结果验证了所提出方法的有效性.

     

基于SKPCA的卫星整流罩空调系统传感器故障检测研究

针对卫星整流罩空调系统对传感器故障检测的高可靠性的要求,在分析常见故障模式的基础上,采用了基于统计量核主元分析（ SKPCA）的故障检测方法,建立整流罩空调系统传感器故障检测模型,对整流罩空调系统传感器容易出现的偏置故障进行了验证实验。实验结果验证了SKPCA方法在整流罩空调系统传感器故障检测中的正确性和有效性。