Optimization of the magnetostatic field in SMES devices

The aim of this paper is to show how SMES devices, if arranged with more than two magnetic dipoles, can perform better. The analysis is carried out either considering or not the presence of a ferromagnetic shield. In the latter case, shape optimization of the iron shield is performed using a combined stochastic/deterministic method. The paper shows how advantages can be taken by evaluating the sensitivity matrix of the iron shape optimization by means of a Lagrangian formulation of the Maxwell's equations.