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A novel evolutionary algorithm is used for the optimization of the thrust force of the stages of an electromagnetic aircraft launch system, based on a double-sided tubular linear induction motor. A semianalytical model allows for a fast and accurate prediction of all the electromagnetic quantities in the device, including the thrust force, the back electromotive force, the distribution of the induced current density, and the average magnetic flux density in the teeth. Using the semianalytical formulation, the characterization of the machine is greatly facilitated, so allowing a fast evaluation of the cost function and of the design constraints. [ABSTRACT FROM PUBLISHER]

In this paper, a passive permanent-magnet (PM)-based magnetic levitation system is presented and its stability is discussed. The suspension is assured by the repulsive force of properly shaped PMs placed on both the guideway and the vehicle. The interaction between the motional-induced currents on conductors attached to the guideway and the PMs on the armature produces a stabilization force. Two versions of the device are discussed. In the first, the stabilizing currents are the ones induced on a conductive sheet surrounding the guideway. In the second device, the stabilizing currents flow in an array of null-flux coils. Comparison of the performance of the two proposed systems are performed by a research code developed at the Department of Energy, System Territory and Construction Engineering. [ABSTRACT FROM PUBLISHER]

This paper presents an analytical model for the investigation of the gyroscopic stabilization of the launch package in induction-type coilguns. By a proper arrangement of coils and of their feeding currents, a traveling wave of flux density is produced, which is characterized by axial and azimuthal components of velocity. The resulting action exerted on a conductive cylinder has components in the same directions as the traveling wave. This produces a helical motion of the armature. Since the governing vector field equation is not separable in the cylindrical coordinate, an approach based on the second-order vector potential formulation has been adopted here. [ABSTRACT FROM PUBLISHER]

In this paper, a new approach for the numerical solution of coupled electromechanical problems is exploited with the aim of simulate electromagnetic devices with high-speed moving parts. The considered problem formulation rests on the low-frequency integral formulation of the Maxwells equations and the Newton–Euler rigid-body dynamic equations. The numerical integration of the coupled problem is discussed and developed with a two-step method. The method has been validated by comparison with experimental data (when available) and with results obtained by other numerical formulations. An example of application to a 2 degrees of freedom device based on permanent magnets is finally reported. [ABSTRACT FROM PUBLISHER]

An innovative double-sided tubular linear induction motor is presented, and its optimal design in terms of thrust force is discussed. A dedicated semi-analytical model of the device is developed allowing for fast and accurate evaluation of all the electromechanic quantities in the device, including the thrust force, back-electromotive force, distribution of the induced current, and average magnetic flux density in the teeth. This provides a basis for the design optimization, which has been performed by a novel evolutionary algorithm based on the self-organizing maps. Using the semi-analytical formulation, the characterization of the machine is greatly facilitated, thus allowing a fast evaluation of the cost function and design constraints. Finally, the obtained optimal design is validated by comparison with finite elements method analysis. [ABSTRACT FROM AUTHOR]