The Methods of Condition Monitoring for Circulator of HTGR

Circulator is one of the important components in an HTGR to meet the plant safety and availability. Several methods have been applied for the condition monitoring and in-service inspection especially of reactor cooling pump, which mainly for the light water reactor such as the vibration monitoring, acoustic emission and motor current signature analysis (MCSA). Despite the long experience of these condition monitoring implementation in light water nuclear power plant, however, research is still required to understand the most suitable method for a condition monitoring of the reactor cooling pump for the HTGR based on all possible monitoring methods. It is because that each method is known having its own sensitivity to detect specific faults, sensitive only on one side either the electrical motor side or the pump as well as having its own capability to meet the criteria's to be implemented in a condition monitoring. Therefore, this paper aims to study various condition monitoring methods that are suitable for the implementation in online condition monitoring of circulator in HTGR. Because the circulator or blower has not been commonly explored for the HTGR, this paper describes the common faults in cooling pump of light water reactor, various condition monitoring, and the comparison of the applicability of each method to identify each type of faults. This paper also discusses the challenges and opportunities for further improvement in this condition monitoring research. This research highlighted that the combination of more than one online monitoring techniques with the performance may provide a better solution in identifying various faults and motor degradation. (paper)