Fundamental Studies on Characteristic Evaluation and Application of Bulk Superconductor

1.采用YBCO块材和多块电磁铁，设计并制作了一种新型的主动磁悬浮系统。通过三块和五块电磁铁系统控制悬浮高度实现了连续悬浮，并利用有限元计算程序研究了悬浮体内部的电磁行为。2.提出了一种二维运动的磁悬浮装置，即悬浮式X-Y运输机。针对一个真实的悬浮式X-Y运输机的设计方案，对该运输机的升力和恢复力进行了实验研究，并基于三维混合有限元-边界元法开发了一个新的仿真程序，用于分析高温超导块材的动态电磁特性。然后通过实验和数值模拟，阐明了各种力与超流场和磁场分布之间的关系。3.研制了一种直线同步驱动器，并进行了实验研究， 关于我们 双面初级和场冷YBCO体次级。对同步转矩、起动推力和吸合特性等静态特性进行了实验研究。并开发了基于有限元法的模拟程序，研究了初级绕组产生的磁场作用下YBCO块材内部的电磁行为。4.实验研究了YBCO块材在外加不同幅值和频率的交流磁场作用下的俘获场转变。并利用新开发的基于有限元法的计算机程序进行了数值模拟。在50 Hz的长期外加磁场条件下进行了陷获场衰减实验。衰减突然变大，最后俘获场消失。这意味着，屏蔽电流的分布在体内的时间变化的磁场和瞬态磁通量的运动的结果，在温度上升，并最终减少了被困领域的变化。少

1.A new type of active-maglev system is designed and constructed using YBCO bulk and multiple electromagnets. And the continuous levitation was demonstrated with controlling the levitation height using three and five electromagnets systems and electromagnetic behavior within the bulk was investigated using a FEM computer program.2.A magnetic levitating device was proposed with two-dimensional movement, namely a 'levitating X-Y transporter'. For a real design of levitating X-Y transporter, the lift and the restoring force were examined experimentally and a simulation program was newly developed based on the three-dimensional hybrid FE-BE method to analyze the dynamic electromagnetic behaviors of the HTS bulk. Then the relationship between the various forces and distributions of supercurrent and magnetic field was clarified through experiments and numerical simulation. And the design of a levitating transporter was also performed.3.We fabricated and tested a linear synchronous actuator w … More ith double-sided primary and field-cooled YBCO bulk secondary. We experimentally investigated the static characteristic in points of synchronous torque, the starting thrust and the pull-in characteristics. And we developed a simulation program based on FEM to investigate electromagnetic behavior within the bulk exposed to the magnetic field generated by the primary winding.4.The transition of trapped field was experimentally investigated while applying external AC magnetic field with various amplitude and frequency to a disk-shaped YBCO bulk. And the numerical simulation was also performed using a newly developed computer program based on the FEM. The experiment of trapped field attenuation was carried out in long term applying field with a frequency of 50 Hz. The attenuation is abruptly large and finally the trapped field is disappeared. This means that shielding current distribution within the bulk is changed by the time-varying magnetic field and the transient magnetic flux movement results in temperature rise and finally the reduction of the trapped field. Less