Abstract: Fault detection of a class of networked control systems with asynchronous sampling clock and transmited data dropout is studied.Based on the fixed rate of the data packet dropout and the time-delay more than one sampling period and the conditions of data arrival of actuator，the state observers of system is designed，which is modeled as an asynchronous dynamic system with rate constraints on events，then the exponential stability condition of the observer system is given.When a fault occurs，the observer residue can change rapidly to detect the fault.A numerical example shows the effectiveness of the proposed method.

Key words: networked control systems, fault detection, swiched system, long time-delay, packet dropout

摘要： 针对同时具有网络诱导时延和数据包丢失的异步时钟网络控制系统，假设数据包丢失率一定，网络诱导时延大于一个采样周期，根据执行器接收数据包的情况，设计了系统的故障观测器，将其建模为具有事件率约束的异步动态系统，基于该模型进行了稳定性分析，当条件满足时，整个系统是指数稳定的。在此基础上研究了系统的故障检测，当系统发生故障时，观测器残差能够迅速发生跳变，从而检测出故障的发生。仿真示例验证了所提出方法的有效性。

关键词: 网络控制系统, 故障检测, 切换系统, 长时延, 丢包