Alternating Current Loss of Superconductors Applied to Superconducting Electrical Machines

Superconductor technology has recently attracted increasing attention in power-generation- and electrical-propulsion-related domains, as it provides a solution to the limited power density seen by core component, electrical machines. Superconducting machines, characterized both high efficiency, can effectively reduce size mass compared conventional machine designs. This opens way large-scale purely applications, e.g., all-electrical aircrafts. The alternating current (AC) loss of superconductors caused time-varying transport currents or magnetic fields (or both) impaired efficiency reliability superconducting bringing severe challenges cryogenic systems, too. Although much research been conducted terms qualitative quantitative analysis AC its reduction methods, remains crucial problem for design highly efficient especially those operating at speeds future aviation. Given that critical review on advancement regarding not reported during last dozen years, combined with this paper aims clarify status provide useful reference researchers working adopted materials, analytical formulae, modelling measurement approaches, well techniques low-temperature (LTSs) high-temperature (HTSs) low- high-frequency have systematically analyzed summarized. Based authors’ previous characteristics HTS coated conductors (CCs), stacks, coils frequencies, existing quantification methods elucidated, multiple suggestions respect machines put forward. article reviews applied first time. It is believed help deepen understanding deliver helpful guideline development superconductivity.