Yannick Vuillermet

Scalar Potential Formulation and Inverse Problem Applied to Thin Magnetic Sheets

Our goal is to identify sheet steel magnetization with near field measurements. Indeed, direct calculation of the whole magnetization is impossible because the remanent part of the magnetization is nondeterminist. Consequently, our strategy is to obtain a magnetostatic formulation able to compute magnetic field as close as possible to the sheet and which is adapted to solve an inverse problem. In this paper, a scalar potential integral formulation is introduced and compared to a magnetization formulation. We are especially interested in the magnetic anomaly created by ferromagnetic ships.

Optimization of low voltage metallized film capacitor geometry

Thermal constraint is one of the major cause of capacitor failures. In this paper, a loss model, based on electrode current distribution, is first established to determine, by numerical simulation, a temperature mapping of capacitor. This mapping is successfully compared to measurements. Then a shape optimization, coupling losses computing and finite-element method, is led in order to find parameters that give the best lifespan and the larger reactive power provided. Very interesting new geometries have been found out; they allow an increase in reactive power greater than the increase in volume