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Division Spotlight
Mathematics & Computation
Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has since been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that Unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. local time on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
Gokhan Corak, James A. Turso, Kenan Ünlu (Penn State)
Proceedings | Nuclear Plant Instrumentation, Control, and Human-Machine Interface Technolgies (NPIC&HMIT 2019) | Orlando, FL, February 9-14, 2019 | Pages 618-628
The safe and effective control of nuclear reactors is of significant interest to the research reactor community and nuclear power utility industry. Numerous advanced control algorithms have demonstrated superior reactor control over the past several decades – primarily on simulated reactors. Among these, state feedback control has been applied to virtually every type of dynamic system. This paper focuses on developing an accurate model of the Penn State TRIGA Reactor simulation and creating a state feedback controller/state observer design using self-powered Vanadium and Rhodium neutron detectors (SPND) as feedback sensors. This work is the first attempt to use these type of sensors in a closed-loop feedback system for reactor control. The foundation of the equations in Simulink has been derived from normalized point kinetics equations and core averaged thermal-hydraulic equations. The self-powered detector dynamics may be developed from basic activation/decay balance differential equations. Results demonstrate that the TRIGA Simulink model developed compares well with the actual TRIGA Reactor data. Self-powered neutron detectors are well-suited to monitor steady-state reactor power. Due to their dependence on radioactive decay after irradiation to produce a current signal, self-powered detectors have significant delay times associated with them, making them inadequate for real-time feedback control. The long delay associated with the normal detector models can only realistically be used for applications where this delay can be tolerated, such as post-accident power monitoring. A major contribution of this paper is the development and application of detector inverse models, which null-out delays introduced by the physics of the detector. Results demonstrate that the inverse detector models have no delay which is desirable for the reactor closed-loop control. SPNDs need no external power to produce current levels consistent with ion chambers and may prove to be a vital component for closed-loop nuclear reactor control in the future. The successful application of an advanced control algorithm i.e., state-feedback control with self-powered neutron detectors, demonstrates that this technology may be applied in closed-loop nuclear reactor control and safety systems not only for power plant applications but for applications such as space nuclear reactors as well.