Preliminary Study of the High-Power Superconducting Transformer

摘要

A mathematical analysis is given of the concept that the size of a heavy-duty power transformer can be significantly reduced by using superconducting windings. By solving the differential equations for an iron-core transformer with resistanceless windings, and deriving a general expression for leakage inductance, it is shown that the iron core is indispensable no matter how small the cross section of the winding conductor. Calculations, based on the d-c behavior of niobium-tin superconducting wire, lead to a lower limit of around 50% for the reduction in overall weight of transformers in the 10 megawatt class. Overall efficiency is computed for a superconducting transformer cooled by a Carnot refrigerator or a gas liquefier. An appendix describes experiments on small superconducting transformers. (Author)