Calculation of AC Magnetic Losses from the Experimental Field Profiles in a Coated Conductor Under Various External Fields and Temperatures

• Published in: IEEE transactions on applied superconductivity Vol. 18; no. 2; pp. 1341 - 1344
• Main Authors: Yoo, J., Lee, S.M., Jung, Y.H., Lee, J., Xuan, D.N., Youm, D., Kim, H., Ha, H., Oh, S.S.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01.06.2008; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: AC loss; Applied sciences; coated conductor; Conductors; current profile; Electric connection. Cables. Wiring; Electrical engineering. Electrical power engineering; Electromagnets; Electronics; Energy loss; Exact sciences and technology; Hall effect devices; Hysteresis; Magnetic field measurement; Magnetic flux; Magnetic losses; Materials; scanning Hall probe; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Superconducting devices; Superconducting films; Superconducting magnets; Temperature; Various equipment and components; External field; current profile; Coated material; Inverse problem; Hysteresis loss; Energy loss; Critical current; Iron loss; scanning Hall probe; Flux density; Superconducting tapes; Electrical conductor; AC losses; coated conductor; AC loss
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2008.921331

We developed a method for the estimation of AC loss in superconducting tapes. First we measured the field profiles, H(x, H a ), near the surface of a coated conductor (CC) using the scanning Hall probe method. Here, the x axis was parallel to the in-plane transverse direction of the CC tape and H a is the external field applied in normal direction with respect to the tape surface. Then from H(x, H a ), we calculated the current profiles, J(x, H a ), by the inversion method. From J(x,H a ) and the corresponding flux densities, we calculated the hysteretic energy losses per cycle, Q M ldr H a was decreased from H peak to -H peak stepwise, and the temperatures were 77 K and 72 K. We estimated Q M for various values of H peak . We calculated the dimensionless characteristic function, g, which are defined by Q M /(mu 0 I c 2 ). Here I c is the critical current. Our g is similar to the Brandt's theoretical g although the current profile, J(x, H a ), is somewhat different.