Coated conductor arrangement for reduced AC losses in a resistive-type superconducting fault current limiter

Author: Šouc J   Gömöry F   Vojenčiak M  

Publisher: IOP Publishing

ISSN: 0953-2048

Source: Superconductor Science and Technology, Vol.25, Iss.1, 2012-01, pp. : 14005-14010

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

The basic element of a resistive superconducting fault current limiter (FCL) can consist of coated conductor tape exceeding a few meters in length and compacted into a cryogenic envelope. This paper is focused on optimizing the arrangement of coated conductors with a non-magnetic substrate for a resistive superconducting FCL. Several configurations have been tested experimentally and theoretically. Two low-loss arrangements have been identified, both utilizing the bifilar configuration, i.e. the currents in two adjacent tapes are identical in amplitude but opposite in direction. The separation between two adjacent tapes s varied from 0.07 up to 2.10 mm. For the lowest examined separation s the AC transport loss of the straight bifilar model decreased by more than one order with respect to the AC transport loss in the single-tape configuration. Further AC loss decrease is achieved when the pair of tapes carrying opposite currents forms a flat pancake coil. We developed a numerical model in order to analyze the influence of distance between adjacent tapes. To achieve agreement between experimental and numerical results it was necessary to incorporate a lateral distribution of critical current density in the tape. The remaining differences between the results of experiment and calculation can be explained by analysis of experimental imperfections. Finally we suggest an empirical fit for the prediction of AC loss of a practical superconducting fault current limiter.