Modeling­ and­ measurement ­of ­the ­voltage ­signal­ in ­HTS ­flux­ pumps

High-temperature superconductor (HTS) flux pumps can be proper alternatives to energize HTS magnets or rotor windings in electrical motors and generators. They perform in a contact-less way avoiding brushes, as well as inefficient current leads and their cryogenic problems. In this work, the performance of dynamo-type HTS flux pump is investigated in detail via numerical modeling based on MEMEP [1], paying special attention to the voltage signal. We assume an E-J power law relation and magnetic field-dependent critical current density J_c(B). We study the cases of open circuit, close circuit and connection to a coil with large inductance. We also build a demonstrator to experimentally benchmark the modeling showing good agreement. We found that J_c does not play a major role in the open-circuit voltage but J_c(B) is key for the pump performance. In conclusion, MEMEP is suitable to model flux pumps, enabling optimization and proof-of-concept tests.