Loss analysis of a model transformer winding

In the paper we present an analysis of AC losses in windings of a 14 kVA superconducting transformer with Bi-2223/Ag winding. AC losses of individual pancake coils of the secondary winding were measured. Discussion of the meaning of AC loss measurements in individual pancakes is presented. Measurement of loss in short samples (critical current in external magnetic field, transport current losses) was done and the results were compared with losses in the winding under operating conditions using available published data. An effect of temperature on winding losses was also studied.