Simulation for the Fault Current Limiting Operation of REBCO CORC Superconducting Cables With Different Core Materials

Abstract

With high power density and low loss, CORC superconducting cables composed of RE <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$-$</tex-math></inline-formula> Ba <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$_{2}$</tex-math></inline-formula> Cu <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$_{3}$</tex-math></inline-formula> O <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$_{7-\delta }$</tex-math></inline-formula> (REBCO)-coated conductors are of great interest for power transmission applications. They can also effectively be designed to serve as fault current limiters, thanks to their sharp superconducting-to-normal transition. Coupled electromagnetic-thermal finite-element simulations implemented in COMSOL Multiphysics were developed and validated against the published results for the fault current limiting (FCL) performance of two CORC cables of REBCO-coasted conductors wound on either copper or stainless steel cores. For improved accuracy, temperature dependencies of electrical and thermal properties of all component materials were considered in the simulations. The simulations were performed in the cross sections of the cables for every individual layer of each REBCO tape to deliver comprehensive understanding of the evolution of the current distribution and temperature rise in those layers. The studies can suggest approaches to optimize cable design for FCL applications by assessing the role of individual components. In the article, possible computational errors, challenges, and improvements are also discussed.