Modeling of Self-Heating Mechanism in the Design of Superconducting Limiters

We propose a modeling method to simulate how the local temperature rises, due to power dissipation, and how this affects the performance of a high temperature superconductor (HTS) limiter. For given material properties, power, and frequency we determined, by use of both electromagnetic and thermal modeling, the spatial distribution of the temperature rise across an HTS transmission line. This temperature rise in turn affects the local description of the superconductor nonlinearities. To model this effect, we use an iterative technique that combines the Weeks-Sheen method to calculate the current-density distribution with a finite-element method to calculate temperature rise at each point of the transmission line. Simulations of coplanar waveguide HTS limiters on sapphire and quartz are presented.