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The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Lightbridge announces first U-Zr fuel rod samples extruded at INL
Lightbridge Corporation announced today that it has reached “a critical milestone” in the development of its extruded solid fuel technology. Coupon samples using an alloy of zirconium and depleted uranium—not the high-assay low-enriched uranium (HALEU) that Lightbridge plans to use to manufacture its fuel for the commercial market—were extruded at Idaho National Laboratory’s Materials and Fuels Complex.
Luigi Scibile, Basil Kouvaritakis
Fusion Science and Technology | Volume 36 | Number 2 | September 1999 | Pages 139-164
Technical Paper | doi.org/10.13182/FST99-A98
Articles are hosted by Taylor and Francis Online.
The plasma vertical position in a tokamak can be open-loop unstable with time-varying dynamics. The limitation in the output power of the control amplifier makes the time-varying unstable system particularly difficult to control. Fixed-coefficient linear controllers usually fail to maintain control in the presence of large disturbances, like edge-localized modes (ELMs), which saturate the amplifier output. During the saturation period, the vertical position of the plasma will grow exponentially with the unstable eigenvalue and may reach values that cannot be controlled by the energy provided by the control amplifier, which is limited by practical constraints. The primary sources of disturbances and measurement noise that effect the vertical position are the ELMs and the 600-Hz noise from the thyristor power supplies. The former are present in the form of pulses and appear during high-energy confinement plasma configurations. A novel nonlinear controller for the vertical position based on a discrete adaptive near-time optimum control algorithm (DANTOC) is used to stabilize the system, to maximize the stability region, and to provide robustness with respect to the aforementioned sources of disturbances and measurement noise. The controller is tested in simulation for the Joint European Torus tokamak, and the results demonstrate its feasibility in controlling the vertical position for different plasma configurations. The controller is also tested on the COMPASS-D tokamak, and the results demonstrate the improvement with respect to a simple linear proportional and derivative controller in the presence of disturbances and measurement noise.