Protection of superconducting wires and cables used in high power/high field applications

保护高功率/高场应用中使用的超导线材和电缆

• 批准号: RGPIN-2016-06687
• 负责人: Sirois, Frédéric
• 金额: $ 3.28万
• 依托单位: École Polytechnique de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=710358
• 关键词: Protection; superconducting; wires; cables; used

Superconducting materials have the unique property of carrying lossless DC currents below a given critical current (Ic) and critical temperature (Tc). Superconductors considered in this proposal are called “High Temperature Superconductors” (HTS), because they exhibit superconductivity above liquid nitrogen temperature, i.e. 77 K (-196oC), a cheap coolant that is affordable in large-scale applications such as power devices. HTS wires come in the form of flat tapes and can carry amazingly high current densities, e.g. >2 MA/cm2 at 77 K. They are perfect for applications such as high field electromagnets, which allow reaching unprecedented field values, e.g. up to 50 T at 4 K. This could be a game changer in high-resolution magnetic resonance imaging (MRI), nuclear fusion, particle accelerators, etc. Also, since magnets typically require hundreds of kilometers of HTS tapes, they are expected to be the big market “driver” sought for scaling-up the production and reduce costs of HTS wires in a near future. The biggest challenge with superconducting devices is to protect them reliably against thermal instabilities that can destroy them rapidly. In this proposal, we propose to expand the application range of a concept discovered within my research group and that is called “current flow diverter” (CFD). This concept allows speed-up by an order of magnitude the propagation of a thermal instability when it occurs, which considerably simplifies the protection of HTS devices, in particular HTS magnets. It is seen as a potential breakthrough in the discipline, and therefore deserves serious consideration in the short term. The technology was awarded a U.S. patent in May 2015, and further I.P. could arise form short-term research, with potentially wide market if it penetrates the MRI market. Within this project, the following main objectives will be pursued: 1) Find an effective and economical approach to implement the current flow diverter (CFD) concept on long lengths of commercial HTS tapes 2) Understand the impact of a hot spot nucleation in high-current cables made of many HTS tapes (e.g. Roebel or TASC cables) under various experimental conditions 3) Evaluate the impact of using the CFD concept combined with state-of-the-art protection systems for HTS magnets These objectives are aligned with the ultimate goal of my research program, which is to “allow the emergence of a new generation of compact and efficient superconducting devices for improving security of supply in power systems and enable the emergence of high field HTS magnets”. Along the project, it is planned to train 3 Ph.D. students, 5 Master's student, and 5 summer interns. Some parts of the project will be carried out with international partners in order to take advantage of existing infrastructures and speed-up the generation of research results.

超导材料具有在给定临界电流 (Ic) 和临界温度 (Tc) 以下承载无损直流电流的独特特性。该提案中考虑的超导体被称为“高温超导体”(HTS)，因为它们在液氮温度（即 77 K (-196oC)）之上表现出超导性，液氮温度是一种廉价的冷却剂，可在功率设备等大规模应用中使用。 HTS 电线采用扁平带的形式，可以承载惊人的高电流密度，例如77 K 时 >2 MA/cm2。它们非常适合高场电磁体等应用，可以达到前所未有的磁场值，例如4 K 下高达 50 T。这可能会改变高分辨率磁共振成像 (MRI)、核聚变、粒子加速器等领域的游戏规则。此外，由于磁铁通常需要数百公里的高温超导带，因此预计它们将在不久的将来成为扩大生产规模和降低高温超导线成本的巨大市场“驱动力”。超导器件面临的最大挑战是可靠地保护它们免受热不稳定性的影响，热不稳定性会迅速破坏它们。在这个提案中，我们建议扩大我的研究小组发现的一个概念的应用范围，这个概念被称为“电流转向器”（CFD）。这一概念可以使热不稳定性发生时的传播速度加快一个数量级，从而大大简化对高温超导设备（特别是高温超导磁体）的保护。它被视为该学科的潜在突破，因此在短期内值得认真考虑。该技术于 2015 年 5 月获得美国专利，并进一步获得 I.P.可能会从短期研究中产生，如果它渗透到 MRI 市场，则可能具有广阔的市场。 在该项目中，将实现以下主要目标： 1) 找到一种有效且经济的方法，在长长度的商用高温超导带上实施分流器 (CFD) 概念 2) 了解在各种实验条件下由多种高温超导带（例如 Roebel 或 TASC 电缆）制成的高电流电缆中热点成核的影响 3) 评估使用 CFD 概念与最先进的高温超导磁体保护系统的影响 这些目标与我的研究计划的最终目标是一致的，即“出现新一代紧凑高效的超导器件，以提高电力系统的供电安全性，并实现高场高温超导磁体的出现”。 项目预计培养博士3名。学生 5 名，硕士研究生 5 名，暑期实习生 5 名。该项目的某些部分将与国际合作伙伴一起开展，以利用现有基础设施并加快研究成果的产生。