Rolling Wheel Abrasion Condition Monitoring of Control Rod Drive Mechanism in Nuclear Reactor

Abstract

Abstract During the operation of in nuclear reactor, the reliability is largely influenced by the changes of working states of control rod drive mechanism. The abrasion of rolling wheel is one of the most serve faults leading to the control failure. To monitor the rolling wheel in the control rod drive mechanism in nuclear reactor, a new recognition method based on complexity of the singular spectrum entropy has been introduced. In this method, the singular spectrum entropy of vibration signal of the system is firstly calculated. Then an index of brain wave information complexity is used to define the singular spectrum entropy complexity. The complexity index is more sensitive to the uncertainty of the signal and it can effectively reflect the intensity of the random shock signal by abrasion which makes it possible to assess the abrasion condition. Through the control rod drive mechanism of whole life test, it is proved that this method can be used in nuclear reactor control rod drive mechanism rolling wheel abrasion condition monitoring with proper accuracy.