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The paper describes a procedure to optimize the configuration of magnetically levitated high-speed transport systems of electrodynamic type. The procedure is based on the definition of a suitable analytical objective function, with given rated values of speed, levitation and propulsion forces. The function takes into account the system efficiency, as well as the material saving, and fulfils design constraints such as coil size ranges, upper and lower boundaries of electromagnetic and mechanical quantities. An example application is given, starting from a reference configuration and applying a multi-variable search technique.

A new method for minimizing the eddy-current losses in the magnetic shields of the superconducting coils of electrodynamic, magnetically levitated trains. The technique optimizes the configuration of the on-board superconducting and on-ground levitation coils to reduce the harmonic fields on the shield surface that give rise to circulating eddy currents. According to an example application, the method is able to lower losses by 40%.

An analytical formulation was used to derive the propulsion force required by a linear synchronous motors (LSM) to drive a magnetically levitated vehicle with electro-dynamic suspension features. The calculations considered the geometries of the superconducting coils in the air-core long-stator machines and the field coils of the on-board superconducting magnets. The LSM propulsion force was determined from the coefficient of mutual inductance between the two windings.

In EMS-MAGLEV high-speed transport systems, devices for propulsion, levitation and contactless on-board electric power transfer are combined in a single electromagnetic structure. The strong coupling among the windings affects the performance of each device and requires the utilization of numerical codes. The paper describes an overall optimization procedure, based on a suitable mathematical model of the system, which takes into account several items of the system performance. The parameters of the model are calculated by an automated sequence of FEM analyses of the configuration. Both the linear generator output characteristics and the propulsion force ripple are improved applying the procedure to a reference configuration. The results are compared with the results obtained by a sequence of partial optimizations operating separately on two different subsets of the geometric parameters. Index Terms - Electromagnetic optimization, High-speed transport systems, Linear synchronous motor, Magnetic levitation of electromagnetic type.

The paper presents a fully automated procedure to optimize the performance of the on-board generator used in electromagnetic Maglev trains. The procedure utilizes FEM analyses to determine the mathematical model of the generator and then calculates the generator output characteristics by means of step-by-step numerical simulations. On the basis of these characteristics, a suitable objective function is defined. The function is minimized, iteratively changing the geometrical configuration until a stop criterion is satisfied.

The paper describes a procedure to determine the propulsion force produced by the linear synchronous motors used in magnetically levitated vehicles of electromagnetic type. The formulation enables to compute the instantaneous value of the force starting from the winding inductances calculated via FEM numerical analysis. The results are compared to the ones obtainable by means of two other procedures implemented in a commercial FEM code and show that, under the same accuracy, the proposed procedure requires less calculation time.

The paper describes the application of a code based on the surface current method to optimize a magnetic suspension device. The code can handle nonlinear magnetic materials by an iterative adjustment of the values of the magnetic permeability, with a performance estimation which fairly agrees with nonlinear FEM analyses. Thanks to the code flexibility in the input/output management, its application may be more straightforward than in the case of commercial FEM codes, with comparable accuracy and calculation time. Index Terms--Magnetic levitation, nonlinear magnetics, optimization methods, surface current methods.

This paper proposes a decoupled d-q model of double-star interior-permanent-magnet (IPM) machines, whose stator consists of two three-phase winding sets displaced by an arbitrary angle. The model is based on the elaboration of the inductance parameters and is obtained by deriving a transformation that diagonalizes the original 6 x 6 stator inductance matrix of the machine. In the derivation of the transformation, the common assumption of the regularity of the mutual inductances between the two three-phase sets is omitted. Thus, the transformation diagonalizes the stator inductance matrix even if the mutual inductances do not have specific symmetry. It is demonstrated that in order to obtain decoupled reference frames in such a case, the transformation depends on the machine parameters. The validity of the machine model is verified by experimental tests with a double-star IPM machine, in which the two three-phase winding sets are displaced by 30 electrical degrees. [ABSTRACT FROM AUTHOR]