Fast control coil is one of the most important components for EAST device to control the vertical stability of plasma. However, once the heating power of EAST is updated to 36 MW, fast control coil doesn't adapt to the new operation state and couldn't provide effective control for plasma vertical instability. Thus, insulation material with ITER-like magnesium oxide is developed to withstand high radiation and the coil position is also relocated to obtain more effective instability control. Given the relocation of fast control coil, electromagnetic load acting on coil-self and feeders are calculated based on elliptical integral and Ampere force law. The electromagnetic load as volumetric force is interpolated into the finite element analysis model to analyze the stress state on fast control coil. Finally, the design-by-analysis method is adopted to evaluate whether the stress could satisfy the specified acceptance criteria. The study will provide theoretical reference for the update of fast control coil from the perspective of electromagnetic load.

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To achieve much higher operation parameters of EAST device, some key components are upgraded. Fast control coil as one of the key components is updated by using novel stainless steel mineral insulation conductor and the turns are increased to 4, which means the coil's operation environment becomes more severe and larger loads will be encountered. The coil joint is apt to be destroyed in view of the potential defects during the fabrication. Given the numerous advantages, the induction brazing is being considered for the conductor joint connection. The copper mock up is used to carry out the feasibility analysis. Based on the structural size of copper tube, the brazing parameters are calculated and a 2 turns splitting induction coil is designed. Some influence factors effecting the induction efficiency are analysed. It will provide guidance for choice of power supply and the optimization design of induction coil. In addition, the induction experiment is launched and comprehensive joint performance tests are subsequently performed. The test results indicate the joint overall performance could satisfy the basic engineering design requirement, but also some defects are found and more study should be carried out and to further improve the brazing quality.

The Edge Localized Mode coil is the key component to prohibit the phenomena of disruptive instability occurring in the edge of Tokamak plasma. The coil is made of Stainless Steel Jacketed Mineral Insulated Conductors. And the different pieces of conductor are connected by joints. During the normal operation of Tokamak device, the joints will be shocked by the electromagnetic and thermal loads. Thus, it is necessary to perform the mechanical analysis to verify whether or not the ELM joint has sufficient safety margin to resist the impact of the coupling field. To get the load boundary conditions for the mechanical analysis, the electromagnetic and thermal analysis are launched first. Then the obtained temperature and electromagnetic force density are inserted into the mechanical analysis model. And the equivalent stress is calculated subsequently. The analysis results indicate there is stress intensity. To mitigate the stress intensity, the local structural optimization is employed. Finally, the stress evaluation is carried out based on analytical design. The assessment results demonstrate the optimized model has sufficient safety margin to withstand the shock of multiple loads.

The Central Solenoid Model Coil is a hybrid superconducting coil being developed in Institute of Plasma Physics Chinese Academy of Sciences. The R&D of Central Solenoid Model Coil will lay the foundation for the fabrication of China Fusion Engineering Test Reactor Central Solenoid coil. One of the main purposes during the R&D of Central Solenoid Model Coil is to verify its mechanical performance under the complicated load cases. In order to efficiently and accurately carry out the mechanical analysis, some necessary parameters such as the electromagnetic state under assembly error, the thermal contact resistance and the equivalent material property of conductor winding packet should be calculated in advance. The electromagnetic state here mainly refers to the asymmetric magnetic field and electromagnetic force. The calculation of magnetic density is based on elliptical integrals, the results will provide guidance for the assembly optimization of coil modules. And the subsequently obtained electromagnetic force will offer load boundary condition for the coil stability analysis. The thermal contact resistance is calculated under the assumption that the interface asperity approximately obeys the Gaussian distribution. The thermal contact resistance will be used in the thermal analysis. And the key advantage is which makes the prediction of preload force variation more accurate during coil the cooling down process. The equivalent material property is calculated by using generalized Hook's law and finite element method. Based on the equivalent material property, the coupling analysis model of CSMC will be significantly simplified. Moreover, it makes CSMC full model analysis under non-uniform loads become possible.