Research on Operating Reliability of Multi-Modular High Temperature Gas-Cooled Reactor Nuclear Power Plant Based on Equipment State

Abstract Compared with nuclear power plants (NPPs) with single nuclear steam supply system (NSSS) module, Multi-modular High Temperature Gas-Cooled Reactor (MHTGR) has a larger scale of equipment and more complex human operation activities. It is necessary to study the operating reliability of MHTGR from the perspective of NPP equipment to alert the operator the current status of NPP. In this paper, an MHTGR operating reliability model is proposed based on equipment state. Markov process method is used for equipment or system modelling. The system states are simplified to avoid the state explosion in the model. Based on the sharing forms, the operating reliability model of the whole MHTGR is established with system set classification method. Several operating reliability indices are proposed from multiple perspectives, including power generation capacity, system failure severity, and operating reliability level. The abnormality of HTR-PM600 helium circulator system is used as an example to verify the operating reliability modeling method. The experimental results show that the research can reflect the impact of equipment status on plant operation, which helps operators to identify operation risks, improve overall perception awareness, so as to improve the operation performance of MHTGR NPPs.