On-Line Monitoring Applications in Nuclear Power Plants

Doktorsavhandling, 2009

As the current generation of nuclear power plants have passed their mid-life, increased monitoring of their health is critical to their safe operation. This is especially true now that license renewal of nuclear power plants has accelerated, allowing some plants to operate up to 60 years or more. Furthermore, many utilities are maximizing their power output through uprating projects and retrofits. This puts additional demand and more stress on the plant equipment such as the instrumentation and control (I&C) systems and the reactor internal components making them more vulnerable to the effects of aging, degradation, and failure. In the meantime, the nuclear power industry is working to reduce generation costs by adopting condition-based maintenance strategies and automation of testing activities. These developments have stimulated great interest in on-line monitoring (OLM) technologies and new diagnostic and prognostic methods to anticipate, identify, and resolve equipment and process problems and ensure plant safety, efficiency, and immunity to accidents. The foundation for much of the required technologies has already been established through 40 years of research and development (R&D) efforts performed by numerous organizations, scientists, and engineers around the world including the author. This thesis provides examples of these technologies and demonstrates how the gap between some of the more important R&D efforts and end users have been filled by the author providing the nuclear industry with the means to meet regulatory requirements, comply with technical specification provisions, or resolve operational and maintenance issues. In doing so, emphasis is placed on the author’s most significant contributions to development and implementation of noise analysis and OLM technologies for remote testing of the static and dynamic performance of process instrumentation sensors while they remain installed in operating nuclear power plants.