Fast Coupled Thermoelectric and Magnetic Model to Simulate the Transient Behavior of Inductive and Resistive Superconducting Fault-Current Limiters

The nonlinear dependence of the resistance of high-temperature superconductors (HTSs) on current, temperature, and magnetic flux density is the basis of the operation of some superconducting power equipment. By modeling the resistance, to simulate in detail the transient behavior of such devices in power systems. In that regard, the finest and most accurate models employ the finite-element method (FEM). Nevertheless, the most common approach in power systems remains the lumped parameters using a classic thermal–electrical analogy. Thus far, there has not been a general method that can combine fine geometrical features of the superconducting device given by finite-element models and the flexibility and computational speed of lumped-parameter models (LPMs). A new model is proposed here to bridge both modeling philosophies and benefit from their advantages. This model, referred to as finite-element lumped-parameter model (FELPM), couples an FEM with an LPM in the same framework. The resulting FELPM is compared with two existing LPMs for the two main topologies of superconducting fault-current limiters (SFCL): resistive (RSFCL) and inductive (ISFCL). All the models are validated against experimental data from the literature when available. It is shown that the new approach yields reasonable computation times, especially in the case of inductive superconducting fault-current limiters. It is argued that such a proposal could be expanded to analyze transients of superconducting power components in more complex electrical networks.