Digitalization of Pulse Signal Processing for Ex-Core Instrumentation System in Nuclear Power Plants

Abstract

Nuclear power plants (NPPs) are globally important sources of clean energy. However, high operation and maintenance (O&M) costs are one of the factors hindering the development of NPPs. In this study, we focused on the development of a digital algorithm for ex-core instrumentation systems (EISs) to reduce O&M costs, given that the digitalization of EISs is not progressing compared with other instrumentation and control systems in NPPs. Specifically, we developed a digital algorithm for pulse signal processing in EISs, which traditionally require a significant amount of hardware and maintenance efforts. Our purposes were to simplify the configuration and reduce the O&M costs associated with pulse signal processing. To validate the algorithm, we used a detector emulator and a research reactor. Additionally, we explored a new approach to reduce the workload associated with a discrimination characteristics test (DCT) in EISs. The results of this study demonstrated that the proposed algorithm is effective in achieving good linearity within ±5% of the span and response performance with a delay time of 5 ms, which are required for EISs. Furthermore, the proposed method for the DCT shows promising results in reducing the time required for the test compared with conventional methods.