Proactive degradation management

The longer-term operations (LTO) of existing nuclear power plant requires new approaches to detecting, characterizing, monitoring, and managing degradation and predicting remaining life of critical systems and components. A proactive approach, using online monitoring is employed to identify and enable the management and mitigation of degradation, especially if degradation can be detected early. Proactive approaches to manage component life and degradation require online tools to detect degradation early in the lifecycle, and estimate remaining useful life (RUL) of the degraded component or system. Several methods have been proposed for prognostics such as reliability data-based methods that use historical time-to-failure data to model failure distributions and predict the time-to-failure. Effects-based methods compute a degradation or damage index and correlate the quantity with the probability of failure. The RUL is typically estimated based on the time for the damage index to exceed some predefined threshold.