Numerical Analysis of High-Temperature Superconductors With the Critical-State Model

A numerical method is proposed to analyze the electromagnetic behavior of systems that include high-temperature superconductors. The algorithm uses the finite-element method and the critical-state model, and it solves two-dimensional and axially symmetric problems that include superconductors and other materials. The main advantages of the algorithm are its speed, its robustness, and its ease of coupling with circuit equations. This method is used to analyze two different systems: 1) Magnet-superconductor levitation system-the levitation forces are calculated. In order to validate the model, experimental results of such a system are obtained and compared with simulation results. 2) Nine-wire superconducting cable. Parallel and series-type configurations of the current driven in the wires are analyzed. Hysteresis ac losses are also calculated and compared for both scenarios.