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Today, industry has not fully embraced the matrix converter solution. One important reason is its high control complexity. It is therefore relevant to propose a simpler but efficient modulation scheme, similar as three phase VSI modulators with the well-known symmetrical carrier-based ones. The modulation presented in this paper is equivalent to a particular Space Vector Modulation (SVM) and takes into account harmonics and unbalanced input voltages, with the same maximum voltage transfer ratio (86%). The aim of this work is to propose a simple and general pulse-width-modulation method using carrier-based modulator for an easier matrix converter control. Furthermore, a simple duty cycle calculation method is used, based on a virtual matrix converter. Finally, simulations and experimentations are presented to validate this simple, original and efficient modulation concept equivalent to matrix converter SVM.

RÉSUMÉ. Cet article présente une nouvelle stratégie de modulation de largeur d’implusion destinée à réduire les courants de mode commun dans les applications de variation de vitesse utilisant un onduleur à trois niveaux de type neutral-point-clamped. Il détaille l’implantation de cette commande par un modulateur à porteuses en dents de scie permettant de contrôler les degrés de liberté apportés par la stratégie. ABSTRACT. This paper presents a new pulse-width-modulation strategy for the reduction of common-mode currents in adustable-speed-drive applications using a three-level neutral-pointclamped inverter. It is implemented through a saw-tooth carrier-based modulator which makes it possible to control the degrees of freedom provided by the strategy.

Adjustable-speed drives involve common-mode voltages, which generate common-mode currents flowing to the ground through stray capacitances of electric machines. These currents are known to provoke premature motor-bearing failures, as well as electromagnetic interferences disturbing neighbor electronic devices. Furthermore, high-voltage applications involve high levels of these conducted emissions, which must be lowered by using bulky and expensive filters. This paper aims at elaborating a new pulsewidth-modulation (PWM) strategy in order to reduce the common-mode currents generated by threelevel neutral-point-clamped inverters. The proposed strategy also provides the ability to balance the neutral point of the dc-bus capacitors. Experimental results both in time and frequency domains confirm that the new PWM improves the electromagneticcompatibility behavior of the drive compared with conventional strategies.

High-Frequency (HF) transformer is a central part of isolated HF power converters. Its parameters, in particular leakage inductance and losses, have a significant impact on the overall converter performances. With the increase of switching frequencies linked to the use of SiC and GaN based active devices, the control of the HF transformer parameters becomes essential. A HF transformer is usually designed without considering its surrounding. However, the latter can have a significant impact on the transformer's performance. In this paper, the effect of an aluminum casing surrounding the transformer is studied and quantified for two parameters: The transformer leakage inductance and the supplementary losses. The goal is to consider the casing effect in the early design stage of power converters.

This article presents an experimental setup ded- icated to the analysis of magnetic noise and vibrations in radial flux electrical machines. Both electromagnetic excitation and structural response of the electrical machine are simpli- fied to provide the first benchmark of the phenomenon of electromagnetically-excited noise and vibrations. The test bench properties as well as the magnetic, vibration and acoustic upcoming extensive measurements are shared to the scientific community, providing a clear reference case to compare differ- ent

This paper presents an innovative Low Losses Modulation of the Matrix Converter. Its principle is to minimize the cumulated switched voltage in each cell by increasing and decreasing progressively the output potential of each matrix cell. This modulation can be applied to all conversion matrices previously proposed for the matrix converter modulation and can be easily implemented with a triangular carrier based modulator adapted for matrix converter cells. The proposed modulation involves the use of all vectors present in the matrix converter space vector approach, including the 6 rotating vectors. Simulations verify the losses decreasing, but also reveal a significant reduction of the output voltages THD, and a very slightly increasing of the input currents THD.

Organizing international conferences leads to emission of greenhouse gases (GHG). Even though, some conferences are devoted to “greener” systems (e.g. IEEE VPPC), the transport of attendees and the local organization of the conference are not “carbon free”. Consequently, some experiences are reported in this paper in order to reduce the ecological footprint of the conference itself and also to mitigate the emitted GHG for international congresses.

Optimal design of a double-sided linear induction motor using finite element models is complex and time consuming. Two strategies are tested to overcome these difficulties: firstly, the surrogate model-assisted optimization approach where computationally expensive functions are approximated by fast analytical models; secondly, the Efficient Global Optimization that is based on the progressive construction of a Kriging model used to drive the optimization problem. A multi-objective optimization is achieved with these both strategies applied on a finite element model. The resulting Pareto fronts are analyzed and compared in order to select the most appropriate method to take the good decision in afford time

Matrix (MC) and indirect matrix (IMC) converters are direct three-phase to three-phase power converters providing variable frequency and amplitude control of their output voltage. These converters are compact solutions which can be used on industrial adjustable speed drive applications for induction motors. This paper deals with the comparison of the matrix and indirect matrix converter silicon losses for classical industrial applications with constant RMS current load (similar to a constant motor torque). The indirect matrix converter control is extracted from the matrix converter modulation so as to ensure identical instantaneous modulation. Furthermore, the chosen modulation strategy reduces the IMC losses by allowing zero-current switching on the IMC rectifier stage. This paper presents a new reduced losses modulation adapted for indirect converter based on a modified matrix converter modulation which reduces switching voltage step level during a pulse width modulation period. The losses simulations shows that the power losses peak value is about 20% smaller for the matrix compared to the indirect converter. Hence, the matrix cooling system can be significantly reduced compared to the indirect one. The modified modulation increases the number of gate drivers required from six to twelve in the indirect converter rectifier side in comparison with the classical DPWM modulation, but allows to obtain a 14% decrease of its average losses compared to the classical modulation.

Matrix and two stage matrix converters are direct three-phase to three-phase power converters providing variable frequency and amplitude control of their output voltage. These converters are compact solutions that can be used on industrial adjustable speed drive applications for induction motors. The two stage matrix converter control is extracted from the matrix converter modulation in order to assure the same instantaneous modulation. This paper deals with the comparison of silicon losses for both converters used in classical industrial applications with constant RMS current load, similar to a constant motor torque. Results show that the direct solution is best for efficiency criteria.

Cet article propose un modulateur simple et synthétique adapté au convertisseur matriciel, basé sur l’introduction d’un convertisseur virtuel. Le but de ce travail est de construire une Modulation de Largeur d’Impulsion (MLI) simple et générale pour le contrôle des convertisseurs matriciel industriel. La solution proposée est équivalente à une modulation vectorielle (SVM) particulière. Cette solution prend en compte les harmoniques et le déséquilibre des tensions d’entrée et permet de générer un ratio en tension maximale identique aux modulations classiques (86%). Cet article présente tout d’abord la méthode de calcul de la modulation moyenne d’un convertisseur virtuel puis la modulation naturelle associée au convertisseur matriciel, l’ensemble étant validé par des relevés expérimentaux.

Cet article présente une nouvelle stratégie de modulation de largeur d’implusion (MLI) destinée à réduire les courants de mode commun générés dans les applications de variation de vitesse utilisant un onduleur à trois niveaux de type neutral-point-clamped (NPC). Il détaille le principe de la commande et son implantation dans un processeur par un modulateur à porteuses en dents de scie. Celui-ci permet de contrôler les degrés de liberté apportés par la stratégie.

methode de modulation permettant d’agir sur les montages NPC pour contrôler l’équilibrage du bus continu et limitater les pertes par commutation de l’onduleur MLI

méthode permettant par action sur la composante homopolaire de minimiser les pertes dans les onduleurs MLI à n bras

Moteur électrique pour la propulsion des bateaux N° de publication : 2 796 775, N° d’enregistrement national : 99 09559, date de mise à disposition du public du brevet d’invention : 17 août 2001. Exploité par la société PROPELEC, créée à cette occasion.