Calculating stator losses in a helical MFCG

This paper analyzes the transient electromagnetic, thermal, and structural behaviour of the stator turns in a simple helical magnetic flux compression generator (MFCG). One objective is to quantify the losses due to Ohmic heating and flux trapping in the conductors, including the effect of armature motion and armature proximity on the current distribution. A second objective is to determine stress and strain in the windings. The electric current excitation used in the modelling is based on experimental data from tests on a research MFCG. The EM and thermal analyses were conducted using EMAP3D, a 3D FEA code developed at the University of Texas at Austin, with the capability to model relative motion and sliding between conductors. Structural analyses were conducted using a version of DYNA3D that allows state data from EMAP3D to be used as input. Details of the analyses include temperature dependence on electrical, thermal. and mechanical properties.