High power factor shielded superconducting transformer

Abstract

A superconducting transformer comprises a superconducting primary layer arranged to conduct an externally supplied primary electric current around a primary core to establish a magnetic flux through the primary core. The superconducting primary layer is formed on a primary substrate of electrically insulating, non-magnetic material. A superconducting secondary layer is arranged to conduct a secondary electric current around a secondary core. The superconducting secondary layer is formed on a secondary substrate of electrically insulating, non-magnetic material. The primary and secondary cores are made of a non-saturating material. The secondary electric current is generated by stacking the layers to couple the magnetic flux from the primary core to the secondary core. Superconducting vias are formed through the primary, isolation, and secondary layers for making external connections to the transformer. The superconducting transformer may be enclosed within a capacitor shield comprising an insulating layer, an inner superconducting layer, a dielectric layer, and an outer superconducting layer. The inner and outer superconducting layers form a capacitor which may be connected in parallel with the primary layer by the superconducting vias. The capacitor shield isolates external components from the electromagnetic field of the superconducting transformer, and provides a capacitive reactance substantially equal to the inductive reactance of the primary layer for correcting the power factor of the superconducting transformer. Electrical connections are formed through the capacitor shield for making external connections to the superconducting transformer.