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The purpose of this paper is to use a new rational approach for the design of some magnetic couplings. Our method is based on the association of analytical models and an exact global optimization algorithm named IBBA and developed by the third author. The analytical model presented in this paper is more sophisticated than those previously dealt using IBBA. Therefore, some under and over estimating functions have been constructed for those particular problems of design in order to improve the convergence of IBBA. Some optimal results highlight the efficiency of this approach.

This paper proposes to determine the radial forces in bearingless permanent magnet motor topology. We consider normal and tangential components of the magnetic field in the air gap. Their harmonic components and their evolution versus current and rotor position are considered. This allows establishing the semianalytical expressions of the radial forces considering different field sources. Their precision has been verified using a full finite element model and statistic analysis. The advantage of this semianalytical model lies in the swiftness of the different force components evaluation and consequently the reduction of CPU time.Index Terms-Bearingless permanent magnet (PM) motor, CPU time reduction, normal and tangential components of the magnetic field, radial force, semianalytical method, spectral analysis.

In this paper, we compare the transient performances of synchronous and eddy-current magnetic couplings. Based on a two-dimensional approximation for the magnetic field distribution, closed-form expressions for the transmitted torque are first presented. The torque formulas are then used to study the transient responses during a start-up and for a sudden application of a load torque. Simulation results are compared with those obtained from tests. It is shown that overload torque condition leads to the loss of synchronism for the synchronous coupling. A discussion about the benefits and the disadvantages of each topology in terms of transient responses is given.

This paper presents a new methodology of design of electrical rotating machines. The methodology is an extension of previous works of the second author. Indeed, associating combinatorial analytical models with exact global optimization algorithms leads to rational solutions of predesign. These solutions need to be validated by a numerical tool (using a finite-element method) before the expansive phase of hand-making a prototype. Such an automatic numerical tool for computing some characteristic values, such as the torque, was previously developed. The idea of this paper is to extend the exact global optimization algorithm by inserting the direct use of this automatic numerical tool. This new methodology makes it possible to solve design problems more rationally. Some numerical examples validate the usefulness of this new approach. Index Terms-Analytical model, deterministic global optimization, finite-element methods, interval branch and bound algorithm, inverse problem of design, numerical model.

The article discusses about the use of finite elements method (FEM) software in order to help lecturer to teach design of electrical machines. Nowadays, lecturers have less and less time to teach the design of electrical machines. Special tools based on FEM can help them in this task. For the past years, such tools needing sophisticated environments have been realized for designers in industry. Assuming minimum equipment, requirements and guidelines for the realization of a specific tool are presented.

This paper presents a design optimization of an axial-flux eddy-current magnetic coupling. The design procedure is based on a torque formula derived from a 3D analytical model and a population algorithm method. The main objective of this paper is to determine the best design in terms of magnets volume in order to transmit a torque between two movers, while ensuring a low slip speed and a good efficiency. The torque formula is very accurate and computationally efficient, and is valid for any slip speed values. Nevertheless, in order to solve more realistic problems, and then, take into account the thermal effects on the torque value, a thermal model based on convection heat transfer coefficients is also established and used in the design optimization procedure. Results show the effectiveness of the proposed methodology.

This article deals with a methodology for a computer-aided design of electromechanical actuators from the preliminary design of components to the detail design of the electrical motor. The developed library of components for the simulation takes advantage of the non-causal and object oriented characteristics of the Modelica language. The capabilities of the Modelica language and the LMS.Imagine.Lab AMESim or Dymola Platforms are strongly used in order to build a fully integrated process to design and size the different component of the final actuator. The proposed approach is illustrated with the sizing of a flight control actuator.