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High-frequency power converters need electromagnetic interferences filters using common and differential mode chokes with low parasitic capacitance to comply with the electromagnetic compatibility standards. This article proposes a modeling method of this capacitance and ways to minimize it. The studied components are ring core inductors with magnetic materials considered as perfect conductors or with high permittivity, such as nanocrystalline material and most Mn-Zn ferrite materials. In comparison to other work in the literature, the proposed approach takes into account the curvature of the turn, in addition to the coating of the core and the insulation layer of the wire. The hypotheses, used in this article to simplify the real geometry, are compatible with two-dimensional (2-D) approaches to compute the parasitic interturns and turn–core capacitances. These capacitances are evaluated thanks to the 2-D finite element method. The obtained model allows accurate evaluation of the effect of turn–core space on the parasitic capacitance, and enables to reduce its value with a limited impact on the volume of the magnetic component.

The Darwin model, which simultaneously incorporates resistive, capacitive, and inductive effects but neglects the radiation one, has recently attracted more and more attention in the research area. For our industrial application needs, the finite-element (FE) system to solve derived from the Darwin model generally has a large size, which is beyond the capabilities of the direct solvers due to the memory limitation. In this work, a specially designed formulation amenable to an iterative solver is proposed for industrial applications. Moreover, a detailed comparison of different cases is carried out on two different examples.

The modeling of the capacitive phenomena, including the inductive effects becomes critical, especially in the case of a power converter with high switching frequencies, supplying an electrical device. At a low frequency, the electro-quasistatic (EQS) model is widely used to study the coupled resistive-capacitive effects, while the magneto-quasistatic (MQS) model is used to describe the coupled resistive-inductive effects. When the frequency increases, the Darwin model is preferred, which is able to capture the coupled resistive-capacitive-inductive effects by neglecting the radiation effects. In this work, we are interested in specifying the limits of these models, by investigating the influence of the frequency on the electromagnetic field distributions and the impedance of electromagnetic devices. Two different examples are carried out. For the first one, to validate the Darwin model, the measurement results are provided for comparison with the simulation results, which shows a good agreement. For the second one, the simulation results from three different models are compared, for both the local field distributions and the global impedances. It is shown that the EQS model can be used as an indicator to know at which frequency the Darwin model should be applied.

High-frequency static converters requires inductors, common and differential mode chokes with a low equivalent parallel capacitance. To reduce it, this paper proposes first a semi-analytical model of this capacitance for inductors made with coated ring cores of nano-crystalline material. This model is based on 2D finite element method to compute the turn-turn and turn-core parasitic capacitances, taking into account loose windings. Then the total capacitance is computed thanks to an energetic approach. The model is validated against measurements performed on one core for several numbers of turns. Since the model shows that the capacitance is almost linear with the parasitic turn-core capacitance, specific devices are proposed to increase the distance between turns and core and thus decrease the capacitance. It is demonstrated that a small increase in overall volume allows to divide the equivalent parallel capacitance of a common mode choke by almost a factor of three while increasing its overall volume by only 37%.

The stray capacitance of inductors impairs their high frequency impedance. A semi-analytical model is proposed for inductors with conductive core to gain insight for ways to decrease stray capacitance for high frequency power electronic applications. First the elementary capacitances are simulated thanks to 2D electrostatic finite element method (FEM), then an energetic approach is used to compute the global stray capacitance. Experimental verification has been performed on a nanocrystalline ring core. Relative error to the measurement shows that the proposed model improves the accuracy, notably by properly taking into account spaces between turns and between turns and core.

The embedded energy conversion systems onboard vehicles impose strong constraints on power density (low weight and volume) and robustness. Several solutions can be used to achieve these objectives which consist in acting either on the design of the static converter or on the electric machine. In this paper, we propose to act on the two systems together. Thus, the increase in the power density of the converter will be achieved by using wide band-gap semiconductor power devices like the SiC or GaN. These components are very small and able to operate at high frequency, thus reducing the dimensions of passive components and of the cooling system used. To increase the reliability of the electric machine, a multiphase PMSM is used. In this paper, the proposed design method of the integrated GaN inverter into a machine is presented. It will be used for the realization of an integrated GaN inverter into a multiphase PMSM.

To address the new challenges arising from the higher penetration of renewable energy in electrical grid, Demand Side Management (DSM) and Demand Response (DR) aim to involve the residential as well as industrial consumers in the grid equilibrium. Ensuring benefits for both utility and users requires the consumers sensitivities to be understood and then included in the Energy Management System (EMS). For this purpose, the cost is the predominant and most often only factor taken into account in the literature, although in the residential sector other concerns influencing electricity consumption behaviour have been observed. This paper presents an EMS based on a neighbourhood of consumers modelled at the level of their appliance and incorporating 6 consumption profiles along three sensitivities: cost, environment and appliances shifting comfort. A multi-agent optimization is lead by a central aggregator but performed locally by the household using multi-pass Dynamic Programming (DP), thus ensuring privacy protection for the stakeholders.

La montée en fréquence des convertisseurs statiques de puissance oblige à dimensionner les filtres de compatibilité électromagnétique en prenant en compte les éléments parasites de ces derniers. L’objectif est alors d’obtenir un modèle circuit de la bobine de mode commun sur une large plage de fréquence (150 kHz à 30 MHz ici), puis d’utiliser ce modèle pour dimensionner une bobine de mode commun pour le respect d’une norme (DO-160-B ici). L’équivalence circuit du modèle de Debye de la perméabilité magnétique complexe permet de simplifier le dimensionnement de l’inducteur avec la prise en compte de la chute de perméabilité avec la fréquence. La solution semi-analytique de la bobine optimale prend en compte la non-saturation du noyau, et le remplissage de la fenêtre de bobinage, le tout avec un coût de calcul modéré. La géométrie optimale est alors utilisée dans un modèle de la capacité parallèle équivalente de l’inducteur pour prédire avant réalisation sa valeur et la maintenir en deçà du maximum calculé pour le respect de la norme.

Les capacités parasites des bobines impactent leur impédance à haute fréquence. Un modèle semi-analytique de la capacité parasite équivalente pour des bobines à noyau conducteur (nanocristallin) est proposé pour expliquer son origine et la réduire, notamment pour des applications de filtrage pour la compatibilité électromagnétique (CEM) à haute fréquence. Une approche énergétique est utilisée pour calculer la capacité parasite équivalente à partir du nombre de tours et de la valeur des capacités parasites élémentaires issues de simulation éléments finis. Les erreurs relatives par rapport aux mesures montrent que le modèle proposé améliore la précision de la prédiction par rapport aux modèles classiquement utilisés dans la littérature et prend en compte correctement l’évolution avec le nombre de tours et les espacements inter-spires, et spire-noyau.

Le sujet de thèse porte sur l’étude des composants magnétiques utilisés dans les filtres de perturbations électromagnétiques des convertisseurs d’électronique de puissance. Il est bien connu que les convertisseurs statiques sont des sources de perturbations conduites qu’il faut réduire afin de respecter les normes de compatibilité électromagnétique (CEM). Une des solutions couramment utilisée pour réduire ces perturbations est l’installation de filtres CEM entre le convertisseur et le réseau électrique. La première partie du manuscrit est dédiée à la présentation du contexte de la thèse, avec la problématique de la CEM et les solutions de filtrage. Dans la seconde partie, nous présentons la modélisation de l’impédance de la bobine de mode commun du filtre CEM, avec la prise en compte des comportements à haute fréquence, pour son dimensionnement. Ainsi, un modèle des propriétés magnétiques basé sur l’équation de Debye est proposé, auquel est ajouté pour les ferrites, de type Mn-Zn, un modèle de capacité matériau d’ordre fractionnaire. Dans la troisième partie, la capacité parallèle équivalente (CPE) est calculée à partir des capacités élémentaires, tore-spire et inter-spires, déterminées par la méthode des éléments finis en deux dimensions, en tenant compte de la courbure des spires. Dans la dernière partie, le modèle de l’impédance de la bobine de mode commun est utilisé pour le dimensionnement d’un filtre de mode commun. Les résultats obtenus montrent que la conception à l’aide des modèles proposés permet l’optimisation du volume de la bobine. Finalement, l’application de cette méthode a permis de définir un indicateur permettant le choix du matériau magnétique qui minimise le volume de la bobine. Mots clés : électronique de puissance, compatibilité électromagnétique, filtre CEM, bobine de mode commun, capacités parasites, optimisation du volume This thesis is about the study of the magnetic components used in the electromagnetic interference filters of power electronics converters. It is well known that static converters are sources of conducted disturbances that must be reduced in order to comply with electromagnetic compatibility (EMC) standards. One of the solutions commonly used to reduce these disturbances is the installation of EMI filters between the converter and the power network. The first part of the manuscript is dedicated to the presentation of the context of the thesis, with the EMI problematic and the filtering solutions. In the second part, we present the modelling of the impedance of the common mode choke of the EMC filter, taking into account the high frequency behaviour, for its sizing. Thus, a model of the magnetic properties based on the Debye equation is proposed, to which a fractional order capacitance is added to model the material capacitance of Mn-Zn ferrites. In the third part, the equivalent parallel capacitance (EPC) is calculated from the elementary turn-core and inter-turns capacitances, determined by the two-dimensional Finite Element Method (FEM), taking into account the turn curvature. In the last part, the common mode choke impedance model is used to design a common mode filter. The results obtained show that the design using the proposed models allows the optimisation of the choke volume. Finally, the application of this method has made it possible to define indicators for the choice of magnetic material that minimises the choke volume. Keywords: power electronics, electromagnetic compatibility, EMC filter, common mode choke, parasitic capacitances, volume optimization