Characterisation of a high-T-c coil using short sample data

Characteristics of a circular superconducting coil made with BSCCO-2223/Ag tape depend on the amplitude and direction of the magnetic field in the win dings. The effect can be estimated by studying a short sample of the same t ape. However, the loss voltage-current and the frequency characteristics of a coil deviate considerably from those that are measured on a short sample . In order to estimate the deviation, we compared measured characteristics of few small coils employing up to similar to 10 m of tape with those calcu lated from the short samples data. The comparison includes several arrangem ents of coils and field shaping elements around the coil edges and is perfo rmed in the frequency and temperature range typical for power applications (1-100 Hz and 64 to 78 Kelvin respectively). The results are applied to the design of a 100 kVA - 50 Hz resonator coil with a high quality factor.