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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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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Jul 2024
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Nuclear Science and Engineering
August 2024
Nuclear Technology
Fusion Science and Technology
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.”
Taeseung Lee, Richard B. Vilim (ANL)
Proceedings | Nuclear Plant Instrumentation, Control, and Human-Machine Interface Technolgies (NPIC&HMIT 2019) | Orlando, FL, February 9-14, 2019 | Pages 209-221
The Supervisory Control System (SCS) provides overall coordination of the plant actuators that includes automatically regulating process variables so that performance goals are safely met for all operating modes. The system during normal electric power production operates through a hierarchical structure with steam demand supplied as an input at the top level, and based on this value, coordinated set points are issued to lower level sub-system controllers. Through the use of the Supervisory Control System, hot-side temperatures can be maintained near-constant during transients so that thermal fatigue is significantly reduced from otherwise. The design strategy for the control system regards the plant response to a change in electric generator load as consisting of two components: steady-state and transient. There is the equilibrium state the plant will reach in asymptotic time (steady-state) in response to the changed condition. The steady-state control algorithm, or Load Schedule as it is known, manages steady-state temperatures. There is the dynamic component of the response (transient) which can be regarded as superimposed on the asymptotic state. The Single-Input Single-Output (SISO) Controllers manage the dynamic response component. In this work, the Supervisory Control System is designed for electric power operation of a pool-type metallic-fueled Sodium-cooled Fast Reactor (SFR). 10% step and 5%/min ramp load change cases were simulated with a one-dimensional system analysis code to assess the performance of the SISO controllers.