| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for measuring a critical current in a super conductive cable, the method being capable of measuring a critical current in a superconductive cable with high accuracy using a small capacity electric power source. <P>SOLUTION: In a superconductive cable 1A in which cable cores 10a, 10b, and 10c having superconductive conductor layers 11 and superconductive shield layers 12 are housed in a heat insulating tube 13 A, ends of two cores, 10a and 10 b, are electrically connected with a lead member 2 and a DC power supply 3 is connected to the other ends so that current passes through both cores 10a and 10b reciprocally. A critical current is measured by providing a direct current to the superconductive conductor layers 11 at a fixed change speed. Then is calculated the reduction amount of the critical current decreased by a leakage magnetic field based on the difference between a current applied to the superconductive conductor layer 11 fixed to the core 10a and an induction current passing through the superconductive shield layer 12 fixed to the core 10a. A critical current can be accurately measured by correcting the reduction amount due to the leakage magnetic field for a measured critical current even when a small capacity electric power source is used. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
