Design And Study On Fault Diagnosis Expert System For Reactor Coolant System

In order to improve the safety and economy of nuclear power plant operation, the research on its fault diagnosis related problems is beneficial for reducing human errors introduced by operators, furthermore, is significantly important to ensure that NPPs’ safe,reliable and economic operation. As one of main systems of reactors, the coolant system influences the safety and reliability of reactors significantly. Therefore, research and design on its fault diagnosis system are essential and necessary.With adequate understanding and analysis of the composition and the failure mode, the reactor coolant system fault trees were established. Meantime, the knowledge-based expert diagnostic system with comprehensive functions of device management, condition monitoring,fault diagnosis and treatment decision, was developed by using the real-time database openPlant and programming language C#. According to the monitoring requirements and parameter’s characteristics, the export system realized the function of parameter monitoring by the method of upper and low limit detection and trend detection. In addition, combining the principles of human factor engineering, the condition monitoring human-machine interface was designed. When the parameter became abnormal, it would trigger the alarm system composed by the digital alarm card. Additionally, the digital alarm card records the fault information of signs, causes, and treatment decisions and so on. Thus the result of the fault diagnosis could be got by the alarm card.After the actual operation data of the Hong Yan He nuclear power plant was accessed,human-machine interface could display the real-time monitoring parameters, and the abnormal parameters could trigger the alarm system, with the certain alarm information and the specific coding rules, the corresponding alarm card could be found quickly to diagnose the fault. The effectiveness and reliability of the system designed in this paper was proved.