Multiphysics problems represent an open issue in numerical modeling. Electromagnetic launchers represent typical examples that require a strongly coupled magnetoquasistatic and mechanical approach. This is mainly due to the high velocities which make comparable the electrical and the mechanical response times. The analysis of interacting devices (e.g., a rail launcher and its feeding generator) adds further complexity, since in this context the substitution of one device with an electric circuit does not guarantee the accuracy of the analysis. A simultaneous full 3D electromechanical analysis of the interacting devices is often required. In this paper a numerical 3D analysis of a full launch system, composed by an air-core compulsator which feeds an electromagnetic rail launcher, is presented. The analysis has been performed by using a dedicated, in-house developed research code, named “EN4EM” (Equivalent Network for Electromagnetic Modeling). This code is able to take into account all the relevant electromechanical quantities and phenomena (i.e., eddy currents, velocity skin effect, sliding contacts) in both the devices. A weakly coupled analysis, based on the use of a zero-dimensional model of the launcher (i.e., a single loop electrical equivalent circuit), has been also performed. Its results, compared with those by the simultaneous 3D analysis of interacting devices, show an over-estimate of about 10–15% of the muzzle speed of the armature.

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Solid armatures in electromagnetic rail launchers have to undergo severe electromagnetic, mechanical and thermal stresses. These stresses are unevenly distributed in the armature mainly due to the Velocity Skin Effect. Contrasting this effect reduces the peak to average ratio of the stresses and allows better performance of the device. In this paper, the behavior of a transposed multi-conductor solid armature is numerically investigated by the research code EN4EM (Electric Network for ElectroMagnetics) developed at the DESTEC. The code is based on an Integral Formulation that reduces the magnetic diffusion problem in the analysis of a time-varying electric network. The code enables a strong electromechanical coupling and allows accounting for currents distribution in the rails and in the armature due to the proximity and 'ordinary' skin effects, as well as the velocity skin effect. Preliminary computations have shown an improved (more regular) current density distribution in the armature. This allows increasing the total current on the armature without reaching the melting temperature in the armature. Improved performance of the launcher with transposed armature is predicted.

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The inductive power transfer (IPT) is expected to greatly contribute towards electrification in transportation. In fact, IPT charging technology has the potential to overcome several limitations of conductive charging: in particular, the process can be fully automatable, and both static and dynamic charging are allowed, thus reducing the size of the battery pack. Additionally, safety is increased due to the absence of safety issues related to loss of cable insulation or to the unwanted interruption of the plug-socket connection. This paper presents, from a systematic approach, the design and realization of a prototype for IPT charging of autonomous shuttles in automated warehouses. First of all, the typical mission profile of the shuttle was properly identified, and a storage system based on power-oriented electrochemical cells was sized. Based on that, the architecture of the IPT system was chosen, both for transmitting and receiving sections. The pads were designed for this purpose, by considering the geometric constraints imposed by the manufacturer, through the utilization of the finite elements method. Finally, the power electronic circuitry was also designed. Numerical simulations of the components, as well as of the complete system, were performed and a prototype was built to widely verify the correspondence of the simulation outputs with the results obtained from an experimental measurements campaign.