REBCO FCL Modelling: Influence of Local Critical Current Non-Uniformities on Overall Behavior for Various Tape Architectures

Abstract

REBCO Coated Conductors with very good characteristics are now easily available in hundreds of meter lengths. Their use for resistive fault current limiter applications is constrained by the variations of the critical current density along the length, which may lead to the appearance of destructive hotspot under ohmic fault conditions. In this paper, we present a light 1D model of Coated Conductor FCL that take into account the critical current density variations along the length, assuming a homogenous temperature in the tape cross section. This assumption is discussed by comparing simulation results for a case of quench propagation under constant current with those obtained with a more refined 2D model. The new 1D model is then compared to small scale experiments of DC FCL with very short transient. Finally it is used to study the influence of tape architecture on the behavior of a MW-class DC Fault Current Limiter with critical current non-uniformities and select a suitable candidate architecture for the realization of such device.