Magnetic feedback stabilization of the tearing mode (TM) is numerically investigated, utilizing the MARS-F code (Liu et al 2000 Phys. Plasmas 7 3681) for toroidal tokamak equilibria. With control coil configurations assumed in this study, magnetic feedback partially or fully stabilizes the TM, with either vanishing or finite equilibrium pressure. The best control is achieved by the combination of internal active coils and internal poloidal sensors. The internal and external tearing indices are evaluated for the close-loop system, based on the MARS-F computed mode eigenvalue and eigenfunction, respectively. In the absence of the favorable curvature effect, these two indices are real-valued and quantitatively agree well with each other. For the equilibrium with finite pressure gradient at the mode rational surface, the favorable average curvature effect becomes important and the close-loop tearing index also becomes complex-valued, partly due to interaction of the feedback system with the dissipative wall eddy current response. Isolating the inner layer and outer region response to magnetic feedback, with either proportional or proportional-derivative actions, allows to establish that feedback stabilization of the TM occurs mainly due to modification of the behavior of the external ideal solution, further confirming the analytic result reported in He et al 2021 Phys. Plasmas 28 012504.

利用 MARS-F 代码（Liu等人2000 Phys. Plasmas 7）对撕裂模式 (TM) 的磁反馈稳定性进行了数值研究3681) 用于环形托卡马克平衡。在本研究中假设控制线圈配置的情况下，磁反馈部分或完全稳定 TM，具有消失或有限的平衡压力。最好的控制是通过内部有源线圈和内部极向传感器的组合来实现的。分别基于 MARS-F 计算的模式特征值和特征函数来评估闭环系统的内部和外部撕裂指数。在没有有利曲率效应的情况下，这两个指标是实值的，并且在数量上相互吻合。对于模态有理面上有限压力梯度的平衡，有利的平均曲率效应变得重要，闭环撕裂指数也变为复值，部分原因是反馈系统与耗散壁涡流响应的相互作用。通过比例或比例导数作用隔离内层和外区域对磁反馈的响应，可以确定 TM 的反馈稳定主要是由于外部理想解的行为的改变，进一步证实了报告的分析结果在他等人2021物理学。血浆 28 012504。