Nuclear Reactor Instrumentation and Control Systems
Carol S. Smidts, Stephan V. Arndt · Wiley Encyclopedia of Computer Science and Engineering · 2009
Abstract Three generations of nuclear reactor instrumentation and control systems have been installed consecutively in nuclear power plants. The first used analog technology for instrumentation and relay‐based equipment for control, the second used discrete or integrated solid‐state equipment for both functions, and the current generation uses digital equipment for both. Each generation of systems carries out the same basic functionalities, for example, the monitoring, control, and protection of critical plant parameters and equipment to ensure the safe and reliable functioning of the plant. The progressive shift toward digital systems has been driven by several factors, such as the aging of analog systems and their consequent degradation, the move of industry toward computerized systems, the lack of replacement parts, the added flexibility and enhanced features of digital systems such as self‐test and diagnostics, the ability to store and handle larger sets of data and thus obtain a better understanding of the plant status, and the fact that digital systems are free of drift and do not require recalibration and readjustment of the set points. The progressive shift to digital systems has led the nuclear community to a vibrant debate that centers on the development of an understanding of the side effects of such change. At the center of this debate is the need to understand the impact of introducing software as a major component of these systems. This article provides a brief description of nuclear reactor instrumentation and control systems, characterizes the software used, and discusses the issues raised.