Test results of the SMES model coil-pulse performance

A model coil for superconducting magnetic energy storage (SMES model coil) has been developed. To establish the technology needed for a small-scale 10 0 kW h SMES device, a SMES model coil was fabricated and tested in 1996, Th e coil was successfully charged up to about 30 A and down to zero at the de signed magnetic-field ramp rate for the SMES. Alternating current (AC) loss es in the coil were measured by an enthalpy method. The results were analyz ed and compared with the test results from a short sample. The measured hys teresis loss is in good agreement with that estimated from the short sample results. It was found that the coupling loss of the coil could be describe d as consisting of two components with different coupling time constants. O ne has a short time constant of about 220 ms, which is in agreement with th e test result of a short conductor. The other has a long time constant of a bout 30 s, which was not expected from the test results for the short sampl e. (C) 1999 Cryogenic Association of Japan. Published by Elsevier Science L td. All rights reserved.