Study on Thermally-Controlled Superconducting Device for Synchronous Rectifier of Line Frequency

对超导电力电子装置的关断特性进行了测试，研究了影响其实用化的触发能量损耗问题。作为器件开发的第一步，我们尝试了如下的沟道-栅结：（1）我们提出了NbTi表面覆铜的氧化。我们试着制作沟道和绝缘层。(2)我们提出了一种气相沉积方法。我们尝试在NbTi沟道和栅极层上制作绝缘层。(3)我们尝试在一定的温度下将NbTi箔和NiCr箔与聚四氟乙烯片粘合在一起。它形成沟道-绝缘层-栅堆结构。(4)整理了器件的基本特性和整流等数据，并在国际会议上进行了介绍。（5）在国际会议上进行了降低沟道与栅极间热阻的试验报告。(6)揭示了动磁通式磁通泵在电机中的进一步应用 关于我们 在旋转条件下的超导特性，并发表在日本电机工程师学会会刊和应用超导会议上，揭示了“温控超导开关“用于整流装置的可能性。降低关断能量的研究势在必行。不提高开关效率是不可行的。在本项目下建立了薄保温层的方法。对该模型开关进行了性能试验，并给出了比较提高加热器效率的标准数据。（1）可控整流装置由超导体、绝缘体和加热体多层结构组成。对于每个薄层，优选较小的热导率。为了提高开关效率，建立了低热阻绝缘层和加热层的制备方法。(2)制作在工频下工作的器件，具有最小的开关损耗和几毫秒的恢复时间。(3)明确了开关特性与多个研发器件的结构（设计）参数之间的关系。(4)建立了超导Transformer同步整流电路的电路结构。(5)通过对氧化物超导特性的评价，探讨其应用的可行性。为了制作开关器件，我们提出了科研资助项目（B）（2）“用于工频同步整流器的温控超导电路及器件的研究”。少

Turn-off characteristics test of the superconducting power electronics device has been performed.Loss reduction of the trigger energy, which is obstacle for practical use, has been studied. As first step of device development, we tried to make the channel-gate junction as follows ; (1) We proposed the oxidization of the clad copper on the surface of NbTi. We tried to make the channel and the insulator layer. (2) We proposed a vapor deposition method. We tried to make the insulator layer on the NbTi channel and the gate layer. (3) We tried to glue NbTi foil and NiCr foil with Teflon sheet under certain heat. It forms the channel-insulator-gate pile structure. (4) We arranged the data such as basic characteristics of the device and rectification, and presented at the international conference etc. (5) We reported at international conference etc. on the trial to reduce the thermal resistance between the channel and the gate. (6) We revealed next application on moving flux type flux-pump un … More der rotating condition, and presented in Applied Superconductivity Conference and The Transactions of The Institute of Electrical Engineers of Japan.Obtained results reveal the possibility of "Thermally-Controlled Superconducting Switch " for rectifying device. The study on reducing turn-off energy is requied. There is no feasibility without improvement of switching efficiency. The method of thin insulation layer are established under this project. Performance test of the model switch has been proceeded, and the standard data for comparing improvement of heater efficiency. Furthermore, (1) This controlled rectifying device consists of the multi-layer of superconductor, insulator and heater. With each of thin layer, less thermal conductivity is preferred. To improve switching efficiency, establish the method to yield the insulator and heater layer with low thermal resistance. (2) Fabricate the device which operate under line frequency with minimum switching loss and a few milli-seconds recovery time. (3) Clear the relationships of switching characteristics and the structural (design) parameters with many R＆D devices. (4) Establish the circuit configuration of the synchronous rectifier circuit with the superconducting transformer. (5) Investigate the feasibility to apply the oxide superconductivity, through its characteristics evaluation. To fabricate switching device, we proposed Research Project Grant-in-Aid for Scientific Research (B)(2) "Study on Thermally-Controlled Superconducting Circuit and Device for Synchronous Rectifier of Line Frequency". Less