With the development of network technology, more and more networks (e.g. Internet) have been applied to distributed control systems, whose feedback loop is closed through a real-time network, which is termed the networked control system (NCS). With the development of NCS, the fault diagnosis of NCS has become a hot subject for the security of the NCS. With the introducing of networks in control systems, there exist many problems due to sharing a common network medium, such as network-induced delay, data packet dropout and multi-packets transmission. So, research on fault detection of networked control systems based on Ethernet is of great significance in both theory and practice. Main work and contributions in this dissertation are described as follows: 1). With the strong computation power of the NetCon intelligent node, the fault detection module and control module are placed at the same site. With this configuration, the effect of the closed-loop control for the fault detection and the forward delay do not need to be considered. When a fault happens in the model, the adaptive prediction technique is applied for compensating for sensor delays. Using the observer-based fault diagnosis module and the NetCon configuration software, the on-line fault detection and monitoring for the NCS is achieved. An off-line simulation and a motor control experiment are used to test the feasibility of the proposed method. 2). According to the stochastic properties of the data transmission, the Markov delay model is applied to study the fault detection problem of NCS. With the time stamp in the data packets, at the every mode, the delay value can be obtained and the constant time delay theory can be applied. The randomness of the delay denotes stochastic switching. The dissertation gives the stabililty analysis and sufficient conditions for control. A LMI-based fault detection algorithm for the NCS is proposed. At last, the simulation experiment is used to test the feasibility. 3). According to the demands of the graph interface of the visual supervisory configuration software, the dissertation details the design process of some functions of the software, which considers its generalization and expansion with the tool of the UML. The user can design any graph monitoring module freely in this software environment. The NetCon system provides many powerful configuration functions，such as, figure configuration and virtual instrument. 4). The alarm and event modules are the important part of the NetCon system. It embodies the software value. Following the requirements of the NetCon system, the dissertation gives the analysis and design of the alarm and event module. The component can be combined into a distributed system with other components. The conclusions are given in the final chapter.
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