| 摘要 |
PURPOSE: To reduce eddy current loss by twisting a crystal plane periodically. CONSTITUTION: A rectangular parallelepiped-like layer support body 1 of a metal thin plate has a width (x) of 2 to 3cm, and a thickness (y) of 0.4 to 0.6mm. Two bifiler tapes A1, A2 of electrically anisotropic high temperature-oxide superconductor are wound on the support body 1, two spaces or slits 2 of a width b2 of 0.1 to 1mm exist between the tapes. This way, current (i) flows spirally on the support body 1, flows in the right upward direction in the tape A1, and in the left downward direction in the tape A2. In this case, a critical length is expressed by formula I. In this way, the eddy current loss can be reduced. In formula I,ρis the electric resistance of the superconductor in C direction when critical current density in the C direction exceeds a specified value, (r) is 1/2 of the tape thickness, jc is the critical current density in (a), (b) directions, B is the magnetic flux density, and (t) is the time for effectively suppressing the coupling loss. |
