Development of fault current limiter using MCP Bi-2212 bulk superconductors

2015 Fiscal Year Final Research Report

• Project/Area Number: 25420302
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Electronic materials/Electric materials
• Research Institution: National Institute of Technology, Toyota College
• Principal Investigator: TSUKAMOTO Takehiko 豊田工業高等専門学校, 電気・電子システム工学科, 教授 (10217284)
• Co-Investigator(Kenkyū-buntansha): OIKAWA Dai 豊田工業高等専門学校, 電気・電子システム工学科, 助教 (40707808) ; SUGIURA Toko 豊田工業高等専門学校, 電気・電子システム工学科, 教授 (70206407) ; ANDOH Hiroya 豊田工業高等専門学校, 情報工学科, 教授 (30212674)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: ビスマス系超電導体 / Melt-Casting法 / 炭酸カリウム添加 / 臨界電流 / n値 / クエンチ特性 / 事故電流限流器

Outline of Final Research Achievements

We have investigated the transport and quench properties of Bi-2212 samples doped with K2CO3 and fabricated by the melt casting process (MCP). The critical current and the n values were varied by K2CO3 doping. The Bi-2212 doped with 2.0 mass% K2CO3 was demonstrated to be best suited for current-limiting device applications because it exhibited the largest n value. Furthermore, the critical current was improved by the addition of appropriate quantities of K2CO3. The critical current density Jc for the best sample is about 300 A/cm2. The frequency dependence of the critical current was measured for the MCP sample. The critical current was found to slightly decrease with increasing frequency, owing to the influence of a nonuniform current density distribution in the radial direction of the MCP samples. Then observed critical current and critical temperature had distribution in length direction.

Free Research Field

超電導工学