Quench and mechanical behaviors are critical issues in high temperature superconducting(HTS)coils.In this paper,the quench characteristics in the rare earth barium copper oxide(REBCO)pancake coil at 4.2K are analyzed,...Quench and mechanical behaviors are critical issues in high temperature superconducting(HTS)coils.In this paper,the quench characteristics in the rare earth barium copper oxide(REBCO)pancake coil at 4.2K are analyzed,and a two-dimensional(2D)axisymmetric electro-magneto-thermal model is presented.The effects of the constituent materials,background field,and coil size are analyzed.An elastoplastic mechanical model is used to study the corresponding mechanical responses during the quench propagation.The variations of the temperature and strain in superconducting layers are compared.The results indicate that the radial strain evolutions can reflect the transverse quench propagation and the tensile hoop and radial stresses in superconducting layers increase with the quench propagation.The possible damages are discussed with the consideration of the effects of the background field and coil size.It is concluded that the high background field significantly increases the maximum tensile hoop and radial stresses in quenching coils and local damage may be caused.展开更多
A novel pancake Rogowski coil without magnetic core is introduced in this paper. Owing to its special pancake winding structure, the coil is of low self-resistance and high self-inductance, and thus has excellent low ...A novel pancake Rogowski coil without magnetic core is introduced in this paper. Owing to its special pancake winding structure, the coil is of low self-resistance and high self-inductance, and thus has excellent low frequency characteristic in the self-integral mode. Moreover, because of its unique installation method, the coil has a flexible sensitivity and can be applied under situations where toroidal air-core Rogowski coils or printed aircuit board （PCB） coils are not available. The parameters and performance of the pancake Rogowski coil are presented, and the principle of shielding is given. Measurements of step pulse current and oscillating pulse current by the coil are studied experimentally to illustrate its good linearity, reliable and flexible sensitivity and excellent frequency characteristic, especially its advantage in low frequency characteristic. The pancake Rogowski coil can be designed to assume round, square or rectangle shape, and has thus broad prospects in its application to the current measurement in such areas as plasma physics and pulsed power technology.展开更多
基金the National Natural Science Foundation of China(Nos.11872195,11472120,and 11802036)the 111 Project(No.B14044)。
文摘Quench and mechanical behaviors are critical issues in high temperature superconducting(HTS)coils.In this paper,the quench characteristics in the rare earth barium copper oxide(REBCO)pancake coil at 4.2K are analyzed,and a two-dimensional(2D)axisymmetric electro-magneto-thermal model is presented.The effects of the constituent materials,background field,and coil size are analyzed.An elastoplastic mechanical model is used to study the corresponding mechanical responses during the quench propagation.The variations of the temperature and strain in superconducting layers are compared.The results indicate that the radial strain evolutions can reflect the transverse quench propagation and the tensile hoop and radial stresses in superconducting layers increase with the quench propagation.The possible damages are discussed with the consideration of the effects of the background field and coil size.It is concluded that the high background field significantly increases the maximum tensile hoop and radial stresses in quenching coils and local damage may be caused.
基金supported by Chinese National High Technology Research and Development Program(863 Program)(No.2008AA04Z408)
文摘A novel pancake Rogowski coil without magnetic core is introduced in this paper. Owing to its special pancake winding structure, the coil is of low self-resistance and high self-inductance, and thus has excellent low frequency characteristic in the self-integral mode. Moreover, because of its unique installation method, the coil has a flexible sensitivity and can be applied under situations where toroidal air-core Rogowski coils or printed aircuit board （PCB） coils are not available. The parameters and performance of the pancake Rogowski coil are presented, and the principle of shielding is given. Measurements of step pulse current and oscillating pulse current by the coil are studied experimentally to illustrate its good linearity, reliable and flexible sensitivity and excellent frequency characteristic, especially its advantage in low frequency characteristic. The pancake Rogowski coil can be designed to assume round, square or rectangle shape, and has thus broad prospects in its application to the current measurement in such areas as plasma physics and pulsed power technology.
