Critical Current and Cooling Favored Structure Design and Electromagnetic Analysis of 1 MVA HTS Power Transformer

This paper presents a conceptual design of a 1 MVA/10 kV/0.4 kV high temperature superconducting power transformer by using Dynamically Innovative BSCCO (DI-BSCCO) tapes. The three-phase three-limb iron core is formed by laminated silicon steel sheets at room temperature. The high-voltage (HV) windings take the form of five solenoid groups per phase, where the five solenoids are coaxially placed and connected in series. The preliminary design of the low-voltage (LV) windings includes two winding schemes. One is with the form of five coaxial solenoids in parallel; the other is to use the ten-stacked tapes directly to wind one solenoid with 17 axial turns. The structural designs and electromagnetic analyses are presented with critical current and uniformity of current distribution discussed. The designed 1 MVA HTS transformer has the advantages of smaller volume, lighter weight and less operation loss as compared to a 1 MVA conventional transformer.