New developments on calculating and measuring AC losses in composite superconductors

A method for the complete numerical solution of the Maxwell equation for a multifilamentary wire carrying a transport current and subject to applied fields of arbitrary direction, where both current and applied fields have arbitrary time dependence, has been developed. First results show unexpected differences from analytical models used in the past. From both approaches current degradation effects can be estimated and loss contributions resulting from the combined action of applied field and current can be calculated