除了正确认识故障机理和科学的诊断方法之外 ,汽轮发电机故障在线诊断功能的实现还要受到现场监测条件的限制。文中介绍一个已投入运行的发电机在线故障诊断专家系统。该系统在现有监测条件下 ,综合电厂各类职能人员协同参与诊断的优势 ,采取在线与离线紧密结合的推理运行方式 ,成功地解决了因监测信息不足而引起的确诊故障困难和漏判某些故障等问题。重点介绍了诊断系统的功能结构、运行模式及数据流程 In addition to correctly understanding the fault mechanism and scientific diagnostic methods, the realization of on-line fault diagnosis of turbogenerators is also limited by on-site monitoring conditions. This paper introduces a generator fault diagnosis expert system which has been put into operation. Under the existing monitoring conditions, this system integrates the advantages of various functional personnel in power plant in taking part in the diagnosis, and adopts inference and operation mode combined closely with online and offline to successfully solve the problems of diagnosis and failure caused by insufficient monitoring information Some problems such as failure. The functional structure, operation mode and data flow of the diagnostic system are mainly introduced