Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Tailoring tokamak error fields to control plasma instabilities and transport

Journal Article · · Nature Communications
 [1];  [2];  [3];  [4];  [3];  [1];  [3];  [1];  [3];  [3];  [5];  [5];  [5];  [1];  [3];  [3]
  1. Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
  2. Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States); Seoul National Univ. (Korea, Republic of)
  3. Korea Institute of Fusion Energy, Daejeon (Korea, Republic of)
  4. Columbia Univ., New York, NY (United States)
  5. Seoul National Univ. (Korea, Republic of)
A tokamak relies on the axisymmetric magnetic fields to confine fusion plasmas and aims to deliver sustainable and clean energy. However, misalignments arise inevitably in the tokamak construction, leading to small asymmetries in the magnetic field known as error fields (EFs). The EFs have been a major concern in the tokamak approaches because small EFs, even less than 0.1%, can drive a plasma disruption. Meanwhile, the EFs in the tokamak can be favorably used for controlling plasma instabilities, such as edge-localized modes (ELMs). Here we show an optimization that tailors the EFs to maintain an edge 3D response for ELM control with a minimized core 3D response to avoid plasma disruption and unnecessary confinement degradation. We design and demonstrate such an edge-localized 3D response in the KSTAR facility, benefiting from its unique flexibility to change many degrees of freedom in the 3D coil space for the various fusion plasma regimes. This favorable control of the tokamak EF represents a notable advance for designing intrinsically 3D tokamaks to optimize stability and confinement for next-step fusion reactors.
Research Organization:
Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
Sponsoring Organization:
National Research Foundation (NRF); National Research Foundation of Korea; USDOE
Grant/Contract Number:
AC02-09CH11466
OSTI ID:
2310908
Journal Information:
Nature Communications, Journal Name: Nature Communications Journal Issue: 1 Vol. 15; ISSN 2041-1723
Publisher:
Nature Publishing GroupCopyright Statement
Country of Publication:
United States
Language:
English

References (58)

A universal instability of many-dimensional oscillator systems journal May 1979
A long-pulse high-confinement plasma regime in the Experimental Advanced Superconducting Tokamak journal November 2013
Edge stability and transport control with resonant magnetic perturbations in collisionless tokamak plasmas journal May 2006
3D field phase-space control in tokamak plasmas journal September 2018
A brief history of nuclear fusion journal June 2020
Observation of a reduced-turbulence regime with boron powder injection in a stellarator journal January 2022
Disruption prediction with artificial intelligence techniques in tokamak plasmas journal June 2022
Enhanced performance in fusion plasmas through turbulence suppression by megaelectronvolt ions journal June 2022
Predicting disruptive instabilities in controlled fusion plasmas through deep learning journal April 2019
Demonstration of reduced neoclassical energy transport in Wendelstein 7-X journal August 2021
A sustained high-temperature fusion plasma regime facilitated by fast ions journal September 2022
Magnetohydrodynamic-activity-induced toroidal momentum dissipation in collisionless regimes in tokamaks journal May 2003
Computation of three-dimensional tokamak and spherical torus equilibria journal May 2007
Development of KSTAR Thomson scattering system journal October 2010
Charge exchange spectroscopy system calibration for ion temperature measurement in KSTAR journal October 2010
The importance of matched poloidal spectra to error field correction in DIII-D journal July 2014
Self-consistent perturbed equilibrium with neoclassical toroidal torque in tokamaks journal March 2017
Influence of sheared poloidal rotation on edge turbulence journal January 1990
The interaction of resonant magnetic perturbations with rotating plasmas journal March 1991
Flow shear induced fluctuation suppression in finite aspect ratio shaped tokamak plasma journal May 1995
Interaction of tearing modes with external structures in cylindrical geometry (plasma) journal July 1993
Error field mode studies on JET, COMPASS-D and DIII-D, and implications for ITER journal November 1999
Error field experiments in JET journal April 2000
Chapter 3: MHD stability, operational limits and disruptions journal June 2007
Impact of plasma triangularity and collisionality on electron heat transport in TCV L-mode plasmas journal June 2007
I-mode: an H-mode energy confinement regime with L-mode particle transport in Alcator C-Mod journal August 2010
Progress in understanding error-field physics in NSTX spherical torus plasmas journal March 2010
Sustained suppression of type-I edge-localized modes with dominantly n = 2 magnetic fields in DIII-D journal July 2013
Progress on the application of ELM control schemes to ITER scenarios from the non-active phase to DT operation journal February 2014
Extremely low intrinsic non-axisymmetric field in KSTAR and its implications journal March 2015
Characteristics of type I ELM energy and particle losses in existing devices and their extrapolation to ITER journal August 2003
Zonal flows in plasma—a review journal April 2005
Toroidal modelling of resonant magnetic perturbations response in ASDEX-Upgrade: coupling between field pitch aligned response and kink amplification journal August 2015
Edge localized mode control using n   =  1 resonant magnetic perturbation in the EAST tokamak journal December 2016
Enhanced understanding of non-axisymmetric intrinsic and controlled field impacts in tokamaks journal August 2017
3D field induced collisionless zonal flow decay in tokamak plasmas journal December 2017
Localizing resonant magnetic perturbations for edge localized mode control in KSTAR journal August 2020
Nonlinear energy transfer from low frequency electromagnetic fluctuations to broadband turbulence during edge localized mode crashes journal October 2020
Physics basis for design of 3D coils in tokamaks journal June 2021
Parametric dependencies of locked mode thresholds in KSTAR L-mode plasmas journal June 2021
Optimization of 3D controlled ELM-free state with recovered global confinement for KSTAR with n = 1 resonant magnetic field perturbation journal January 2022
Integrated RMP-based ELM-crash-control process for plasma performance enhancement during ELM crash suppression in KSTAR journal July 2023
First Observation of Edge Localized Modes Mitigation with Resonant and Nonresonant Magnetic Perturbations in ASDEX Upgrade journal June 2011
Role of Zonal Flow Predator-Prey Oscillations in Triggering the Transition to H-Mode Confinement journal April 2012
Observation of Lobes near the X Point in Resonant Magnetic Perturbation Experiments on MAST journal June 2012
Suppression of Edge Localized Modes in High-Confinement KSTAR Plasmas by Nonaxisymmetric Magnetic Perturbations journal July 2012
Observation of a Multimode Plasma Response and its Relationship to Density Pumpout and Edge-Localized Mode Suppression journal March 2015
Pedestal Bifurcation and Resonant Field Penetration at the Threshold of Edge-Localized Mode Suppression in the DIII-D Tokamak journal March 2015
Nonlinear Transition from Mitigation to Suppression of the Edge Localized Mode with Resonant Magnetic Perturbations in the EAST Tokamak journal September 2016
Achievement of Reactor-Relevant Performance in Negative Triangularity Shape in the DIII-D Tokamak journal March 2019
Wide Operational Windows of Edge-Localized Mode Suppression by Resonant Magnetic Perturbations in the DIII-D Tokamak journal July 2020
Active Control of Alfvén Eigenmodes by Externally Applied 3D Magnetic Perturbations journal January 2023
Regime of Improved Confinement and High Beta in Neutral-Beam-Heated Divertor Discharges of the ASDEX Tokamak journal November 1982
In Search of the Elusive Zonal Flow Using Cross-Bicoherence Analysis journal May 2000
Error Field Amplification and Rotation Damping in Tokamak Plasmas journal May 2001
Suppression of Large Edge-Localized Modes in High-Confinement DIII-D Plasmas with a Stochastic Magnetic Boundary journal June 2004
Active Control of Type-I Edge-Localized Modes with n = 1 Perturbation Fields in the JET Tokamak journal June 2007
Control of Asymmetric Magnetic Perturbations in Tokamaks journal November 2007

Similar Records

Overview of recent progress in 3D field physics in KSTAR
Journal Article · Sun Feb 06 19:00:00 EST 2022 · Journal of the Korean Physical Society · OSTI ID:1880119

Tailoring resonant magnetic perturbation to optimize fast-ion confinement during ELM control in KSTAR
Journal Article · Tue Oct 24 20:00:00 EDT 2023 · Nuclear Fusion · OSTI ID:2203572