Citation: Li, X.; Fan, Z.; Wang, S.;
Qiu, A.; Mao, J. A Distributed Fault
Diagnosis and Cooperative
Fault-Tolerant Control Design
Framework for Distributed
Interconnected Systems. Sensors 2022,
22, 2480. https://doi.org/10.3390/
s22072480
Academic Editors: Hamed Badihi,
Tao Chen and Ningyun Lu
Received: 25 January 2022
Accepted: 21 March 2022
Published: 23 March 2022
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Article
A Distributed Fault Diagnosis and Cooperative Fault-Tolerant
Control Design Framework for Distributed
Interconnected Systems
Xue Li, Zhikang Fan, Shengfeng Wang, Aibing Qiu * and Jingfeng Mao
School of Electrical Engineering, Nantong University, Nantong 226019, China; xueleey@163.com (X.L.);
a1024584761@163.com (Z.F.); wangsf@ntu.edu.cn (S.W.); mao.jf@ntu.edu.cn (J.M.)
* Correspondence: aibqiu@ntu.edu.cn
Abstract:
This paper investigates a design framework for a class of distributed interconnected
systems, where a fault diagnosis scheme and a cooperative fault-tolerant control scheme are included.
First of all, fault detection observers are designed for the interconnected subsystems, and the detection
results will be spread to all subsystems in the form of a broadcast. Then, to locate the faulty subsystem
accurately, fault isolation observers are further designed for the alarming subsystems in turn with
the aid of an adaptive fault estimation technique. Based on this, the fault estimation information is
used to compensate for the residuals, and then isolation decision logic is conducted. Moreover, the
cooperative fault-tolerant control unit, where state feedback and cooperative compensation are both
utilized, is introduced to ensure the stability of the whole system. Finally, the simulation of intelligent
unmanned vehicle platooning is adopted to demonstrate the applicability and effectiveness of the
proposed design framework.
Keywords:
distributed fault diagnosis; fault isolation; cooperative fault-tolerant control; distributed
interconnected systems
1. Introduction
With the rapid development of sensing and communication technologies, modern en-
gineering systems are increasingly networked and distributed [
1
]. Further, the large-scale
distributed systems such as power grid and vehicle platooning are generally intercon-
nected, physically or informationally [
2
–
5
]. These kinds of systems are thus referred to as
distributed interconnected systems, which are composed of several subsystems in differ-
ent locations through coupling mechanisms. On the other hand, the increasing size and
complexity of distributed interconnected systems makes the occurrence of faults easier.
Besides, due to the characteristics of interconnection, the fault diagnosis for distributed
interconnected systems is challenging as an incipient fault occurring in any subsystem can
potentially propagate from one subsystem to another and even result in the collapse of the
whole system. The research on fault diagnosis and fault-tolerant control for distributed
interconnected systems is receiving remarkable attention [6–9].
For the most part, the fault diagnosis approaches for distributed interconnected sys-
tems can be divided, according to the information used by the diagnostic units, into three
categories: centralized, decentralized, and distributed fault diagnosis [
10
]. The centralized
fault diagnosis approach employs a centralized diagnostic unit to collect the information
of the whole system and then conducts fault diagnosis for all subsystems. In [
11
], an
interconnected system with disconnected interconnections and packet dropouts was aug-
mented into a switched system, and then a centralized robust fault detection filter was
further designed. Obviously, the centralized approach requires high computation as well
as communication and is not easy to expand, so it is not suitable for large-scale distributed
interconnected systems. In the decentralized fault diagnosis approach, each subsystem is
Sensors 2022, 22, 2480. https://doi.org/10.3390/s22072480 https://www.mdpi.com/journal/sensors
