Optimization of ferromagnetic shields for solenoidal SMES

Ferromagnetic shields for solenoidal superconducting magnetic energy storages (SMES) are optimized with respect to the stray field or the mass of the shield, Two optimization strategies of zero order are compared: the deterministic downhill simplex method and the evolution strategy, a stochastic method. Due to the comparsion a combination of both methods is tested, To guarantee short computation times the underlying nonlinear field analysis is based on an integral equation method.