Pulsed Field Magnetization of YBa2Cu3O7-δ Bulk Assembly for Motor Application

A high-temperature superconducting (HTS) motor has been developed using bulk superconductors as quasi-cryo-permanent magnets to allow a stronger remanent field. In this work, we focus on the in-situ magnetization of the bulk superconductors which is considered one of the main challenges. YBa ₂ Cu ₃ O _7-δ bulks that had been used in the motor were magnetized via pulsed field magnetization (PFM) as single samples and assembly. The peak trapped field achieved via PFM is similar to that achieved via field cooling magnetization at 77 K. For the bulk assembly, the existence of a neighboring bulk superconductor was found to affect the penetration of the magnetic flux during the PFM process especially under low applied fields. This leads to a 3% to 4% reduction in peak trapped field, and 10% to 13% reduction in integrated magnetic flux.