A High Temperature High Reliability Control Rod Position Sensor for Improved Nuclear Power System Instrumentation

Advancements are needed to improve and optimize the performance of existing and future nuclear power plants and nuclear power systems by developing and improving the reliability of advanced instrumentation. A need has been identified for an improved control rod position sensor for fault-free confirmation of control rod drive mechanism (CRDM) function, improving long term reliability, maximizing SCRAM reliability, and minimizing SCRAM disengaging time. The technical challenges of developing such a sensor are: insensitivity to particulates; small size; high reliability; and harsh environment operation, including very high temperatures (600C), high pressures (2200 PSIG), and irradiation. Sporian proposes to work with nuclear power system OEMs to develop such a small, high reliability, high temperature operable, control rod position sensor, based on leveraging Sporians past experience with high temperature sensors and packaging, and facilitative ceramic electronics packaging technologies. In Phase I, Sporian worked with OEMs to develop application suitable hardware and electronics, developed materials/fabrication process, and subsequently prototyped and experimentally evaluated/demonstrated prototype hardware and electronics in an application representative CRDM mockup, and at relevant neutron fluences. Based on the results of Phase I, the Phase II will include materials/process development, several rounds of full system prototyping, and rigorous lab scale testing (including neutron irradiation) focusing on types of testing that promote post Phase I transition-oriented activities. The proposed sensor has the potential to improve public safety and reduce negative environmental impacts by assuring control rod position. A high temperature Hall effect sensor could have a variety of additional applications for position sensing in fossil fuel, transportation and industrial applications. For example, the sensor also has potential to provide blade tip timing and tachometric data for fossil fuel energy generation turbines.