Numerical Simulation of a Bulk Superconductor-Based HTS Dynamo-Type Flux Pump

The high-temperature superconducting (HTS) dynamo is a promising technology for generating large DC currents in superconducting coils without thermally inefficient current leads or bulky power supplies, with potential applications in electric machines and MRI/NMR magnets. A key factor influencing the output voltage and charging performance of HTS dynamos is the magnetic field strength of the magnet(s) rotating past the HTS wire, which is limited in conventional permanent magnet-based designs. In this study, the permanent magnet in the HTS dynamo benchmark model is replaced with a bulk superconductor of similar size. A two-dimensional finite-element model is developed in COMSOL Multiphysics to evaluate the open-circuit voltage of the bulk-based dynamo under different trapped field assumptions corresponding to different bulk operating temperatures. The results show that the bulk-based HTS dynamo can generate significantly higher output voltage than conventional designs, increasing approximately linearly with the trapped field strength. These findings demonstrate the strong potential of bulk superconductors to enhance the performance and coil-charging capability of HTS dynamos.