Activation of trapped field magnets by flux pumping

Although high temperature superconducting trapped field magnets (TFMs) offer great potential as an alternative to 2nd generation YBCO wire, both in cost and performance, their activation poses the greatest challenge to their usage in industry. Field cooled and zero field cooled approaches place too high a demand on motor stator windings. This paper examines a possible alternative in which the magnetic field energy is deposited incrementally using both an ac and a dc source field. The field analysis proceeds by assuming the material to obey the behavior of the Bean model and using elliptic integrals to simulate the field within an axisymmetric geometry.