Development of Fully Superconducting Thrust Linear Actuator Using Temperature Superconductors

在该项目中，我们研究和开发了高温超导(HTS)一次绕组全超导直线驱动器和高温超导块材推进器的基础技术，高推力直驱式电动直线驱动器在工业自动化领域具有巨大的潜在需求。电动直接驱动系统可以实现快速、精确的力控制，这是液压系统和齿轮-马达系统等其他方法难以实现的。然而，使用铜绕组电直接驱动系统来获得高推力，要求绕组的电流密度很大，并且绕组内的焦耳加热非常高。因此，执行器需要一个大容量的电源和一个大尺寸的水冷却系统。另一方面，全超导驱动器可以比铜驱动器更紧凑，具有更大的推力，而功率损耗要小得多。它只需要小尺寸的电源，而且冷却系统可以比水冷系统小得多。我们制作了一种由铋/银护套胶带和YBCO块体推进器组成的初级绕组的执行器模型，研究了推力的基本原理，建立了推力计算的解析模型，验证了分析的正确性。我们还研究了一次绕组和块体超导体的交流损耗特性，这是设计执行器的重要数据。我们开发了一种用于推进器的变极性块状阵列的磁化方法，并证明了该方法的有效性。

In the project, we studied and developed elementary technology for fully superconducting linear actuators with high temperature superconducting (HTS) primary windings and a thruster made of HTS bulks.An electric direct-drive linear actuator with high thrust force has great potential needs in the field of industrial automation. Rapid and exact force control is possible by the electric direct-drive system, which is difficult by other methods such as hydraulic system and gear-and motor system. To obtain high thrust force using an electric direct-drive system of copper windings, however, current density of the windings should be very high and the joule heating in the windings becomes very high. Therefore, the actuator needs a large capacity power supply and a large size water cooling system. On the other hand, the fully superconducting actuator can be more compact and have higher thrust force with much smaller power loss than the copper actuator. It only needs small size power supply and the cooling system can be much smaller than the water cooling system for the copper actuator.We made a model actuator with a primary winding wound of Bi/Ag sheathed tape and thruster with a YBCO bulk and studied basic of thrust force.We made an analytical model to calculate the thrust force and showed the validity of the analysts. We also studied AC loss characteristics of the primary windings and the bulk superconductors which are important data for designing the actuator. We developed a method to magnetize a bulk array with alternative polarity for the thruster and proved the method worked well.