Korea Polytechnic University Industry Academic Cooperation Foundation

Woosuk University Industry Academic Cooperation Foundation

Korea Polytechnic University

Ji Kwang Lee

Chan Gook Park

Kyeong Dal Choi

Woo Seok Kim

Seung Wook Lee

Se Yeon Lee

Byung Wook Han

Yung Il Kim

A method for measuring critical current density of superconductor wires according to the present invention is characterized in that it includes: (a) applying an external magnetic field to the superconductor wires, (b) measuring a magnetization loss of the superconductor wires according to the application of the external magnetic field, (c) normalizing the measured magnetization loss, and then calculating a fully-penetration magnetic field of the superconductor wires according to the normalized magnetization loss, (d) calculating a critical current density of the superconductor wires according to the calculated fully-penetration magnetic field. Therefore, the critical current density of parallel superconductor wires such as stacked superconductor wires may be measured without applying current to the superconductor wires directly.

Measuring method of critical current density of superconductor wires using measurement of magnetization loss

Provided is a multiple transposition method for superconducting wire, by making each superconducting wire unit from second-generation superconducting wires that were firstly transposed and then transposing each superconducting wire unit in such a manner that the phase of each unit can be changed along the length, comprising preparing wires by making curves on superconducting wires in such a manner that the superconducting wires of a thin multiple layer grown epitaxially are slit in zigzags and then making the curves repeatedly and by machining the wires with a desired length; making first-transposed superconducting wire units by combining a plurality of the prepared wires such that curves of adjacent wires come in touch to each other and are superposed; preparing a superconducting wire unit bundle by arranging the first-transposed superconducting wires units and by locating a plurality of the first-transposed superconducting wire units in parallel along the length; and making a second transposition on the first-transposed superconducting wire units by rotating the plurality of superconducting wire units on the central axis of the superconducting wire unit bundle along the length to be twisted and combined with each other.

Multiple transposition method for superconducting wire

A noncontact method for measuring currents flowing through superconductive wires connected in parallel is provided. The method includes arranging hall sensors for measuring voltage levels based on magnetic fields generated around the superconductive wires, setting a matrix relation between the measured voltage values, values of currents flowing through the superconductive wires, and a variable matrix having variables defining relations between the voltage values and the current values, applying predetermined current levels to the superconductive wires a number of times and measuring voltage values through the hall sensors, substituting the predetermined current values and the measured voltage values into the matrix relation to calculate the variables of the variable matrix, and substituting the calculated variable matrix and unknown voltage values, measured by the hall sensors when unknown currents flow through the superconductive wires, into the matrix relation to calculate values of the unknown currents flowing through the superconductive wires.

Noncontact measurement method of currents on superconductive wires connected in parallel

Growing community of inventors

Wanju-gun, South Korea

Ji Kwang Lee