Computer Simulation of a Superconducting Transformer Short-Circuit

Abstract

High critical temperature superconductor power devices have unique characteristics that reduce energy losses during transmission and distribution of electricity. These superconductors allow for high current density, enabling the construction of smaller, lighter, and more transportable installations. A superconducting transformer can significantly reduce the dynamic effects of the short-circuit current during the initial milliseconds of a fault. High temperature superconductor windings, on the other hand, are relatively lightweight and have a low heat capacity. Despite being cryogenically cooled and managing already limited current, the windings made of second-generation high-temperature superconductor can be vulnerable to thermal damage, which may occur in a relatively short timeframe. A numerical study of a short circuit in a three-phase power system with a 10 MVA 115/16.5 kV superconducting transformer is presented in this paper. The superconducting tape's nonlinear electrical and thermal characteristics, as well as heat buildup in the transformer windings during a short circuit, are all taken into consideration by the transformer model.