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

对超导电力电子器件进行了关断特性试验。如何减小触发能量的损耗是实际应用的一个障碍，目前已对其进行了研究。作为器件开发的第一步，我们尝试制作如下的通道-栅极结；(1)提出了在NbTi表面氧化覆铜的方法。我们试着做通道和绝缘层。(2)提出气相沉积方法。我们尝试在NbTi沟道和栅极层上制作绝缘体层。(3)我们尝试在一定的温度下将NbTi箔和NiCr箔与特氟龙片材粘合。形成通道-绝缘子-栅桩结构。(4)整理了器件基本特性、整流等数据，并在国际会议等上进行了展示。(5)在国际会议等上报告了降低通道与栅极之间热阻的试验情况。(6)揭示了在旋转条件下移动磁通型磁通泵的下一步应用，发表在《应用超导会议》和《日本电机工程学会学报》上。所得结果揭示了“热控超导开关”用于整流器件的可能性。因此，有必要对降低关断能量进行研究。不提高开关效率是不可行的。本工程建立了薄保温层的方法。对该型号开关进行了性能试验，并提供了比较加热器效率提高的标准数据。(1)该控制整流装置由多层超导体、绝缘体和加热器组成。每层厚度越薄，热传导率越低。为提高开关效率，建立了生产低热阻绝缘子和加热器层的方法。(2)制作在线频下工作，开关损耗最小，恢复时间几毫秒的器件。(3)明确开关特性与许多研发设备的结构（设计）参数的关系。(4)建立与超导变压器同步整流电路的电路配置。(5)通过对氧化物超导特性的评价，探讨其应用的可行性。为了制造开关器件，我们申请了科研资助项目(B)(2)“热控超导电路及线频同步整流装置的研究”。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