| 摘要 |
PURPOSE:To enable a high temperature superconductor to serve as alternating current wire material by a method wherein a high temperature superconductor very low in critical current density is kept in a flux flow state, and an alternating current is made to flow the conductor. CONSTITUTION:A high temperature superconductive wire material 1 formed of high temperature superconductor through a fusion method is uniform in quality, set lower than prescribed value in critical current density, and wound on a bobbin 3. At this point, the high temperature superconductive wire material 1 is wound on the bobbin 3 so as to make a crystal axis C of the wire material 1 vertical to a central axis O of a coil as shown by arrows. By this setup, an alternating magnetic field is induced along the center O of the coil as shown by an arrow phi, so that a magnetic field vertical to the crystal axis C of the wire material 1 is applied to the wire material 1. By this, the wire material 1 is lessened in flux flow resistance, and the flux flow resistance concerned becomes smaller than a hysteresis loss attendant on the hysteresis effect of a superconductivity shielding current, so that a high temperature superconductor is not required to be formed into a fine filament for the purpose of reduction in loss. |
