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Robustness and reliability of modern synchronous motors require an accurate design of the permanent magnets (PM) while accounting for the motor operating conditions (demagnetizing field, temperature). In this paper, the important attribute of a PM non-linear demagnetization model within a finite element method (FEM) simulation environment is clearly emphasized. To do so, starting from experimental measurement achieved on a NdFeB PM, a toolbox baptized “PM-Demag” has been developed. This toolbox manages the PM history and updates the PM B(H) characteristics depending on the temperature and the PM working point. Finally, a relatively straightforward coupling is implemented with a FEM software and applied to a simple study case. Results show local magnetization loss in the PM due to the combination of both the temperature and the demagnetizing field.

This paper presents an optimization method that deal with control techniques for electrical machines, in order to impose a displacement with a minimum of energy consumption. It’s a generic method; However, its application to electrical machines is complex for implementation. The present work provides the shape of the optimal solution. Moreover, a resolution technique related to the nature of the model is proposed, which facilitate the numerical resolution of costate problem. The method is applied to hybrid stepper motor and the obtained results are then analyzed.

This paper presents a global optimization approach aiming to improve the energy efficiency of electrical machines. The process is made on a hybrid stepper motor allowing to simultaneously optimize design and command. This approach is axed around Pontryagin's maximum principle, which is applied to a magnetodynamic model based on permeances network model. The originality of the proposed approach is to obtain in the same process, the minimization of the energy by optimal control and the minimization of the energy by optimal sizing.

This paper presents a combined experimental/numerical approach to identify the degradation profile of the magnetic characteristics regarding the distance from the cut edge of punched electrical steels. Using a dedicated magnetic measurement device and mechanical hardness measurements, the impacted cutting-edge (I.C-E) distance has been experimentally identified. In association with a magneto-plastic model, the numerical model allows to determine the I.C-E distance and its associated degradation profile by an inverse optimization method.

In this paper, a toolbox baptized “PM-Demag” taking into account the permanent magnet (PM) demagnetization phenomenon has been developed. It is based on a nonlinear demagnetization model which considers the thermal state of the PM and reproduces the knee rounded shape of the B(H) curve. Validations against experimental measurements performed on commercial NdFeB PM are presented.

This paper presents a layered multi-physical model for sizing optimization as well as solving a specific optimization problem of interior permanent-magnet (PM) synchronous machine (IPMSM) for traction application. The advantages of the model structure are the management of the calculation time and the multi-physical aspect taking into consideration the iron losses and the thermal phenomena. An analysis is conducted over an optimization problem with different nested loops and for several operating points of the IPMSM.

This article analyzes and highlights the impact of an iron loss model on temperature estimation within a multi-physical model of a radial-flux permanent-magnet (PM) synchronous machine (PMSM) for traction application. Three iron loss models have been compared in terms of computing time and accuracy within the machine torque-speed plane. This study underlines the iron loss calculation impact on the temperature estimation in the PMSM in relation with the required performances.

This paper presents an optimization method that allows to find the electrical machine control, in order to impose a displacement with a minimum energy consumption. This is a generic method. However, its application to electrical machine is complicated to implement. In this paper, the optimal solution form is proposed for the studied case. Moreover, in order to facilitate the numeric resolution of the auxiliary problem, a technique related to the model nature is proposed. An example with a hybrid stepper motor is presented.

L’article présente une méthode numérique permettant de trouver la commande optimale d’une machine électrique afin d’imposer un déplacement avec une consommation énergétique minimum. La méthode est générique mais son application aux machines électriques est complexe à mettre en oeuvre. Dans ce travail, la forme de la solution optimale est donnée. De plus, une technique de résolution liée à la nature du modèle est proposée facilitant la résolution numérique du problème adjoint. La méthode est appliquée sur le modèle d’un moteur pas à pas hybride et les résultats sont analysés.