Design optimization of high-temperature superconducting power transformers

As HTS transformers begin to move into utility and commercial applications, engineering must optimize the designs for AC losses and total ownership costs while meeting the performance criteria and application requirements. Transformer manufacturers use cost optimization techniques during the design phase to minimize material costs and satisfy the utility's loss evaluation requirement. This paper presents the modifications necessary in transformer design and optimization to handle high-temperature superconductors as the winding material. These changes include AC losses, short-circuit stresses, and cooling loads. Design results are presented for a five-legged core, three-phase, 3.5-MVA power transformer optimized for reduced weight and footprint space for electrical distribution onboard ships.