Simulation of High Temperature Superconducting Bulks Magnetized by Pulsed Field Magnetization with an Electromagnetic-Thermal Coupled Model

TL;DR

This paper presents a coupled electromagnetic-thermal simulation of pulsed field magnetization in high temperature superconducting bulks, exploring parameter effects and proposing coil designs to optimize trapped magnetic fields.

Contribution

It introduces a novel axisymmetric coupled model for simulating HTS bulks during PFM and investigates parameter impacts and coil configurations for improved magnetization.

Findings

Heat generation during PFM affects trapped field performance.

Parameter n values and B0 significantly influence magnetization outcomes.

Controlled magnetic density coils enhance trapped magnetic fields.

Abstract

High temperature superconducting (HTS) bulks can be magnetized to become powerful trapped field magnets (TFMs), which are promising for high-performance electrical applications. To magnetize such TFMs, pulsed field magnetization (PFM) is supposed to substitute field cooling (FC) to provide in situ magnetization. However, the heat generation during PFM, which reduces the trapped field has always been an issue, so numerical simulation of the process is important to provide optimal magnetization strategies. In this paper, HTS bulks magnetized by PFM are simulated with an axisymmetric electromagnetic-thermal coupled model based on H-formulation. Influences of important yet difficult-to-characterize parameters of HTS bulks including n values in the E-J Power Law and B0 in the Kim's Law are investigated. Furthermore, controlled magnetic density distribution coils (CMDCs) which generate a non-uniform field are suggested to further improve the trapped field of HTS bulks compared to split coils proposed previously.