ON-LINE CONDITION MONITORING AND DIAGNOSTICS FOR ROD CONTROL AND ROD POSITION INDICATION SYSTEMS IN NUCLEAR REACTORS

摘要

Many existing pressurized water reactors (PWRs) incorporate a rod control system to move the control and shutdown rods and a digital rod position indication (DRPI) system to monitor the rod positions within the reactor. Aging and obsolescence issues have led to an increase in problems with these systems including analog card failures and coil cable connection problems. These problems, along with plans for plant life extension, have prompted the industry to actively seek new options to monitor the health and accuracy of these systems in order to ensure reliable plant operation. The existing plant equipment provides only limited diagnostic information on the condition and health of these systems. A means to monitor these systems is needed which can warn plant engineers of developing problems so that resources can be put in place before a failure occurs. In an effort to address these technical concerns, Analysis and Measurement Services Corporation (AMS) received two Department of Energy (DOE) Small Business Innovation Research (SBIR) grants to develop techniques for on-line condition monitoring of the rod control and rod position indication systems. The Research and Development (R&D) done under these projects provide more accurate and timely monitoring including diagnostic information that could help prevent numerous problems that can occur with these plant systems. This paper presents the research, development, and results of this work.