What Formulation Should One Choose for Modeling a 3-D HTS Motor Pole With Ferromagnetic Materials?

We discuss the relevance of several finite-element formulations for nonlinear systems containing high-temperature superconductors (HTS) and ferromagnetic materials (FM) in the context of a 3-D motor pole model. The formulations are evaluated in terms of their numerical robustness and efficiency. We propose a coupled h-phi-a-formulation as an optimal choice, modeling the problem with an a-formulation in the FM and an h-phi-formulation in the remaining domains. While maintaining a low number of degrees of freedom (DOFs), the h-phi-a-formulation guarantees a robust resolution and strongly reduces the number of iterations required for handling the nonlinearities of HTS and FM compared to standard formulations.

Automated summary

In this paper, we discuss the relevance of various finite-element formulations for handling nonlinear systems containing high-temperature superconductors and ferromagnetic materials in a three-dimensional motor pole model. The formulations are evaluated based on their numerical robustness and efficiency. We propose a coupled h-phi-a formulation as the optimal choice, which successfully addresses the nonlinearities of HTS and FM while maintaining a low number of degrees of freedom (DOFs).