The AC loss evaluation of central solenoid model coil for CFETR

• In this study, The AC loss of CFETR CSMC is calculated.
• The main AC losses type and mechanics of CFETR CSMC are introduced, where the hysteresis and coupling loss of Nb3Sn and NbTi coil are estimated.
• The low frequency eddy current loss calculation of stainless steel structural components is carried out by ANSYS with 3-D separate model.
• In the case of conductor joints, a 3-D ANSYS code is also used to obtain the eddy current losses for the metal components.

The AC loss of Central Solenoid Model Coil (CSMC) of China Fusion Engineering Test Reactor (CFETR) is calculated in order to be able to determine the allowable excitation current shape in time with respect to the available cooling capacity at liquid helium temperature. Firstly, the structure and operation parameters of CFETR CSMC are summarized including the superconductor, conductor and magnetic field distribution characteristic. Secondly, the main AC losses type and mechanics of CFETR CSMC are introduced, where the hysteresis and coupling loss of Nb3Sn and NbTi coil are estimated using of the model data and a calculation flux density distribution in the cross-section of model coil by ANSYS 2-D model. Thirdly, the low frequency eddy current loss calculation of stainless steel structural components is carried out by ANSYS/EMAG code with 3-D separately for tension rods, plates and beams model. The interaction between several components is not considered. In the case of conductor joints, a 3-D ANSYS code is also used with current force to obtain the eddy current losses for the metal components. Lastly, the individual loss components are summed up. The significant conclusions are made which can provide the valuable guidance for safe operation of CSMC.