jpcs Journal of Physics: Conference Series J. Phys.: Conf. Ser. 1742-6588 1742-6596 IOP Publishing JPCS_1559_1_012056 10.1088/1742-6596/1559/1/012056 J15591056 Paper Frequency-dependent demagnetisation rate of a shielded HTS tape stack Tomkow Lukasz 1 ltt27@cam.ac.uk Climente-Alarcon Vicente 1 Mineev Nikolay 1 2 Smara Anis 1 Glowacki Bartek A. 1 3 4 Applied Superconductivity and Cryoscience Group, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, CB3 0FS, United Kingdom Bruker BioSpin AG, Industriestrasse 26, Faellanden 8117, Switzerland Institute of Power Engineering, Warsaw 02-981, Poland Epoch Wires Ltd. Cambridge CB22 6SA, UK 06 2020 01 06 2020 1559 1 012056 Published under licence by IOP Publishing Ltd 2020 Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Abstract

This work presents results of investigation of crossed-field demagnetization in 2G high temperature superconducting stacks at temperatures in the range of 77 - 20 K and in a variable frequency, corresponding to the particular rotor application.

We propose a method to reduce the demagnetization rate for a given stack configuration necessary for the superconducting rotor operating at a cryogenic temperature. This technique involves 3-D wrapping the stack of tapes with perpendicular layers of similar superconducting properties.

Previous ‘proof of concept’ studies documented some improvements in flux demagnetisation reduction for basic configuration. In the present study a more advanced approach based on magnetic flux shielding is adopted. The presented results provide an important contribution to development for design solutions that aim to increase the operational time before remagnetisation of the stacks would be required.