First all-digital nuclear reactor system installed in U.S.
The U.S. Nuclear Regulatory Commission has licensed Purdue University Reactor Number One (PUR-1) as the first entirely digital nuclear reactor instrumentation and control system in the country.
The upgraded facility in Indiana, originally built in 1962, could pave the way for implementation of digital technology in nuclear power plant reactors. Switching from analog technology to digital could extend the lifespan of existing nuclear facilities as well as increase operating efficiency in new builds.
“The primary advantage of switching to digital is in terms of the data available to the operator,” Robert Bean, PUR-1 facility director and assistant professor of nuclear energy at Purdue told Nuclear Energy Insider.
“Once the data has been digitized it is very straightforward to collect and save incredible amounts of data. This ‘big data’ is then available for an increased amount of analysis to determine optimal operation, to study behavior correlations, and to look for new relationships in the data that can inform further research.”
Costs of installation
Bean said that costs of initial installation of the digital system were comparable with solid-state analog instruments. Plus, as society as a whole becomes more digital, the costs involved in having digital instrumentation and control consoles will inevitably be reduced.
“I would say that implementing digital, physically, was about the same as if we had selected solid state analog equipment,” said Bean. “No matter what system you use, there are motors and switches, and wires and power supplies that have to be connected and tested and verified. The difference is in the design philosophy of circuits versus digital logic. Either way, however, you engage competent teams and test and verify everything along the way.”
As with any new technology, the nuclear power industry needs to be conscious of the advantages and disadvantages before incorporating the technology into plants. Research reactors like PUR-1 are the perfect testing ground to provide some assurances.
As a cyberphysical test bed, collaborators and corporate partners will be able to evaluate simulations of industry reactors using Purdue’s facility as a model and apply lessons learned and best practice improvements to their own reactors.
“A truly significant step forward in our licensing effort was that the U.S. Nuclear Regulatory Commission reviewed and then accepted equipment that had been approved under the KTA standards for use in nuclear reactors in Germany without requiring a complete re-acceptance effort in the United States,” said Bean.
Historically, the U.S. NRC has accepted only parts certified under domestic standards, which are generally cost-prohibitive for use, but they accepted these parts in PUR-1 through the agency’s initiative for a risk-informed and performance-based regulatory process.
“This opens up the ability for the U.S. NRC and our domestic reactor utilities to make use of additional vendors and suppliers as they maintain the existing nuclear fleet and design and plan new reactors," added Bean.
Digital technology also allows reactor facilities to identify performance interruptions which may occur before the scheduled maintenance time, making them safer and extending their lifetime. If parts needed to be replaced, digital ones are less expensive and more commercially available than analog parts.
Going digital means much more data can be processed and analyzed, opening the door to capabilities such as predictive analytics, machine learning and artificial intelligence.
“The digital systems are expected to have a lower life-cycle cost,” says Bean. “More importantly, however, is the wealth of data that will be collected and put to use by the utilities and researchers. There is no doubt, based on impact in other industries, that this data will guide utilities to improved operations and will aid researchers in designing even better reactor systems. Everyone benefits from this.”
The digital conversion of PUR-1 began in 2012 and Purdue developed and built the fully digital system in collaboration with Mirion Technologies and the Curtiss-Wright Corp.
“The nuclear reactor with fully digitized instrumentation and control is a milestone for Purdue’s School of Nuclear Engineering,” added Mung Chiang, the John A. Edwardson Dean of Purdue’s College of Engineering.
“The research and teaching enabled by the new PUR-1 will also contribute to the next chapter of nuclear energy, safety and security in the country.”
That next chapter includes improving the long-term competitiveness of nuclear power, and a switch to digital could see cost savings as a result of a reduction in operational staff. The U.S. Department of Energy (DOE) recently awarded $3.4 million to a research team led by North Carolina State University to perform preliminary development of a Nearly Autonomous Management and Control (NAMAC) system for advanced nuclear reactors. This project aims to use artificial intelligence, machine learning and expert safety analysis to reduce staff count.
Nuclear Energy Insider