Correction of the axial asymmetry of the poloidal magnetic field in the Globus-M spherical tokamak
The toroidal inhomogeneity of the poloidal magnetic field—the so-called error fields that arise due to imperfections in manufacturing and assembling of the electromagnetic system-was measured in the Globus-M spherical tokamak. A substantial inhomogeneity corresponding to the n = 1 mode, which gave rise to a locked mode and led to discharge disruption, was revealed. After compensation of this inhomogeneity with the help of special correction coils, the discharge duration increased and the global plasma parameters improved substantially. A technique for determining and compensating the n = 1 mode inhomogeneity is described, the measured dependences of the penetration threshold of the m = 2/n = 1 mode on the plasma parameters are given, and results of experiments in which record parameters for the Globus-M tokamak were achieved after correction of the poloidal magnetic field are presented.
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- 1.ITER Physics Basis, Nucl. Fusion 39, 2286 (1999).Google Scholar
- 5.H. R. Koslowski, Y. Liang, A. Kramer-Flecken, et al., Nucl. Fusion 43 (2003).Google Scholar
- 7.M. I. Patrov, S. E. Bender, V. K. Gusev, et al., Fiz. Plazmy 33, 99 (2007) [Plasma Phys. Rep. 33, 81 (2007)].Google Scholar
- 10.V. D. Pustovitov, Fiz. Plazmy 24, 530 (1998) [Plasma Phys. Rep. 24, 486 (1998)].Google Scholar
- 11.L. L. Lao, H. S. John, R. D. Stambaugh, et al., Nucl. Fusion 25, 1611 (1985).Google Scholar
- 12.V. K. Gusev, S. E. Bender, A. V. Dech, et al., Zh. Tekh. Fiz. 76(8), 25 (2006) [Tech. Phys. 51, 987 (2006)].Google Scholar
- 13.Progress in the ITER Physics Basis, Nucl. Fusion 47, S128 (2007).Google Scholar