Speakers
Description
Fusion technology, capable of converting energy caused by nuclear-fusion reactions into usable energy, has been widely acknowledged as a potential solution to the global energy crisis and a carbon-neutral future. One of the chief challenges in exploiting fusion reactions is plasma stabilization under extreme temperature, a considerable hurdle that must be overcome [1-3]. The Korea Superconducting Tokamak Advanced Research (KSTAR) is pivotal in addressing this issue, with its In-Vessel Control Coil (IVCC) playing a critical role in achieving plasma stability - a complex challenge within the realm of fusion technology [4-5].
In this study, we investigate the effects of input current magnitude and frequency on the electromagnetic and thermo-mechanical behaviors of a IVCC mock-up model. This approach is necessitated by the constraints associated with direct experimental research on the installed IVCC within the KSTAR vacuum vessel. A key parameter under examination is eddy current loss due to Joule heating, which significantly influences the temperature distribution, as well as thermal stress and deformation within the IVCC mock-up model. We conducted thorough thermal and structural analyses over a range of input current magnitudes (0.5-3 kA) and frequencies (60-320 Hz). Our findings reveal that the heat generation within the IVCC mock-up model's coil case, attributable to eddy current loss, escalates with increasing input current magnitude and frequency. The increase in eddy current loss within the coil case is accelerated by the increased frequency of the input current. As a direct result of this eddy current loss, the coil case temperature rises, subsequently leading to peak thermal stress and deformation within the coil case. However, the magnetic field strength concurrently amplifies with increasing input current magnitude.
Therefore, it's crucial to consider the trade-off relationship between magnetic field generation, heat production induced by eddy current losses, and the mechanical behavior of the IVCC mock-up model. With a comprehensive understanding of these electromagnetic, thermal, and mechanical characteristics, we aim to offer invaluable insights to identify optimal operating conditions for the IVCC.
References
[1] Barbarino M. 2020 A brief history of nuclear fusion Nature Physics 16 890 893
[2] Bigot B. 2015 Nuclear physics: Pull together for fusion Nature 522 149-151
[3] Pironti A. and Walker M. 2005 Fusion, tokamaks, and plasma control: an introduction and tutorial IEEE Control Systems Magazine 25 30-43
[4] Kim H. et al. 2009 Design features of the KSTAR in-vessel control coils Fusion Engineering and Design 84 1029-1032
[5] Kim H.K. et al. 2011 Fabrication and installation of KSTAR in-vessel control coils Fusion Engineering and Design 86 1975-1979
| Keywords | Fusion,KSTAR, In-vessel control coil, Eddy current loss, Numerical study |
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