METHOD OF MEASURING CRITICAL ELECTRIC CURRENT VALUE OF SUPERCONDUCTING WIRE

摘要

A method of measuring a critical electric current value of a superconducting wire (1) is provided with steps of measuring first to m-th (where m is an integer number of 2 or more) electric current values (I<SUB>1</SUB>, I<SUB>2</SUB>,..., I<SUB>m</SUB>) and first to m-th voltage values (V<SUB>1</SUB>, V<SUB>2</SUB>,..., V<SUB>m</SUB>). The first electric current value I<SUB>1</SUB> and the first voltage value V<SUB>1</SUB> are measured by measuring an electric current flowing through a superconducting wire (1) and a voltage generated at the superconducting wire (1) after an electric current is maintained for a predetermined period of time in a state in which the electric current flowing from a constant electric current source (6) through the superconducting wire (1) is set to a first setting value I<SUB>1a</SUB>. A k-th electric current value I<SUB>k</SUB> and a k-th voltage value V<SUB>k</SUB>, (where k is an integer number to satisfy 2=k=m), are measured by measuring an electric current flowing through the superconducting wire (1) and a voltage generated at the superconducting wire (1) after an electric current is maintained for a predetermined period of time in a state in which the electric current flowing from the constant electric current source through the superconducting wire is set to a k-th setting value I<SUB>ka</SUB> that is higher than a (k-1)-th setting current. To this end, a precise critical electric current value can be measured.