# M. HecquetÉcole Centrale de Lille | EC Lille · dept EEA

M. Hecquet

Professor

## About

112

Publications

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1,819

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Introduction

Additional affiliations

October 2008 - present

September 1992 - present

## Publications

Publications (112)

The efficiency of direct-start applications such as pumps or fans can be improved by replacing a squirrel cage induction motor (SCIM) with a line start permanent magnet synchronous motor (LSPMSM). LSPMSM is a super-premium efficiency class IE4 motor, which combines the features of both conventional SCIM and permanent magnet synchronous motor (PMSM)...

The efficiency of direct-start applications such as
pumps or fans can be improved by replacing a squirrel cage
induction motor (SCIM) with a line start permanent magnet
synchronous motor (LSPMSM). LSPMSM is a superpremium efficiency class IE4 motor, which combines the
features of both conventional SCIM and permanent magnet
synchronous motor (PMSM)....

Purpose
This paper deals with the study of the influence of the phase shift between currents and back-electromotive forces (back-EMF) on torque ripple and radial magnetic forces for a low power synchronous machine supplied with 120 degrees square-wave currents. This paper aims to establish a good compromise between efficiency, harmonics of torque a...

Purpose
For a given rotor, the study of the impact of stator MMF from different winding distributions is usually carried out using analytical model under some simplifying hypotheses to limit time computation. To get more accurate results, finite element model is thus more suitable. However, testing different combinations of stator windings with the...

The winding design of an electrical machine is an important task in the whole design process. This leads, for a part, to the magneto motive force which is one of the main quantities to manage for electrical machine performances. Indeed, the latter is directly linked to that of the air gap magnetic flux density and thus to the torque ripples, vibrat...

Nowadays, finite element method is the most accurate approach to study an electrical machine. Howerver, its use in an optimization process remains often unsuitable because it can still require prohibitive calculation times. An analytical approach would then be more adapted but it should be as accurate as possible. In the case of analytical model of...

The electromagnetic noise generated by the Maxwell radial pressure is a well-known consequence. In this paper, we present an analytical tool that allows air gap spatio-temporal pressures to be obtained from the radial flux density created by surface permanent magnet synchronous machines with concentrated winding (SPMSM). This tool based on winding...

This paper deal with the modeling of large power and distribution transformers by means of reluctance network method. It’s about a meshed approach that has the flexibility to fit different transformers topologies. The non-linear behavior and the coupling with the electrical circuit have been considered. The proposed model has the smartness to estim...

This paper presents an experimental setup dedicated to the analysis of noise and vibration due to Maxwell magnetic forces in electrical machines, a significant NVH source in hybrid and electric vehicles traction motors. Both electromagnetic excitations and structural response of the electrical machine are simplified to provide the first public benc...

L’objectif de cet article concerne la comparaison de différentes approches analytiques permettant d’estimer le contenu spatio-temporel des forces radiales dans l’entrefer d’une machine asynchrone. En effet, lors d’une phase de conception intégrant la problématique du bruit des machines électriques, il est intéressant de prédire les harmoniques de f...

The electromagnetic noise generated by the Maxwell
radial force is a well-known consequence. In this paper, we
present an analytical tool which allows obtaining the air gap
spatio-temporal forces from the radial flux density. This tool is
based on winding function and the global air-gap permeance.
The interest lies in keeping results very quickly a...

This paper proposes an improved subdomain model of squirrel-cage induction machines (SCIMs) with imposed stator currents. This new model enables to accurately compute electromagnetic quantities such as air-gap flux density, instantaneous torque and forces, and electromotive force including all harmonic contents. The first improvement is to explicit...

This paper proposes an improved subdomain model of squirrel cage induction machines with imposed stator currents. This new model enables to accurately compute electromagnetic quantities such as air gap flux density, instantaneous torque and forces, electromotive force including all harmonic content. The first improvement is to explicitly account fo...

The aim of this paper is to simulate a large power brushless synchronous generator (BLSG) used for large turbo-alternator brushless excitation systems, under conditions of saturation and rotating rectifier diode failures. A reluctance network coupled with electric circuits and power electronic components integrating the movement and nonlinearities...

In the vibroacoustic analysis of electrical machines, the effect of the tangential magnetic force on the vibrations is generally neglected compared with the radial magnetic force, as well as the effect of the tangential flux density on the radial force, especially for induction machines. In this paper, these two assumptions are studied for the case...

Purpose
The purpose of this paper is to present an original study of industrial inductors with different air-gap materials in order to reduce the vibration and noise of inductors. Acoustic comfort is an increasingly important factor at the design stage of industrial inductors associated to converters. In addition, power converters in the railway d...

This paper presents an analysis of low space order of the air-gap radial Maxwell pressures in surface permanent magnet synchronous machines with fractional slot concentrated windings. The air-gap Maxwell pressures result from the multiplication of the flux density harmonics due to magnetomotive forces and permeance linked to the magnet, the armatur...

This paper reviews the recent developments of semi-analytical subdomains modeling techniques to compute the flux density distribution in electrical machines by the exact solving of Maxwell equations. It is shown that with an appropriate development methodology and numerical implementation, these harmonic models break the traditional compromise betw...

RESUME – Cet article étudie l'effet de l'angle de charge sur les composantes harmoniques des forces de Maxwell (tangentiels et radiaux) dans deux machines synchrones à aimants permanents (MSAP) surfaciques d'architectures très différentes : une machine à 6 dents et 2 paires de pôles, à faible couple et très haute vitesse, et une autre à 120 dents e...

This paper presents an analysis of the air gap radial Maxwell pressures in some three-phase, inner rotor concentrated winding surface Permanent Magnet Synchronous Machine (PMSM). Two modular winding machines and one asymmetric, winding machine are considered and simulated by a Finite Element method (FE). The air gap Maxwell pressure results from mu...

This article demonstrates the use of a mathematical method to efficiently discriminate and
visualize each circumferential vibration wave number involved in the yoke deflections of an electrical machine under
electromagnetic excitations. This post-processing, which can be applied on both experimental and simulation data, allows to calculate the part...

Nowadays, developing electric motorization for land vehicles is essential due to the crucial need to save energy. Regarding the specific speed-torque characteristics (high saturation level, high speed, considerable flux weakening) and manufacturing cost, the Interior Permanent Magnet (IPM) Synchronous Machine (SM) provides considerable advantages....

Nowadays, the development of the electric motorization for land vehicles is essential since the energetic challenge has become very critical. This paper presents the development of a tool used for the optimal acoustic and electromechanical modeling which stands out from standard analytical and Finite Element modeling respectively, due to the high a...

This paper presents an analysis of the air gap radial Maxwell forces in some three-phase, inner rotor Concentrated Winding surface Permanent Magnet Synchronous Machine (CW-PMSM). Two modular winding machines and one asymmetric, winding machine are considered and simulated by a Finite Element method (FE). The air gap Maxwell pressure results from mu...

In this paper, a global optimization methodology is described to pre-design an electric vehicle powertrain in order to find the best compromises between components. The modeled system includes a transmission, an electric machine, an inverter and a battery pack. The challenge is to find the dedicated formulations, with the vehicle performance requir...

The aim of this paper is to study the saturation effect on the electromagnetic and acoustic behavior of Switched Reluctance Machines (SRMs). Two 4-phase SRMs (8/6 and 16/12) are analyzed through numerical models under the hypothesis of linear and nonlinear magnetic material characteristics. The harmonic content of the radial Maxwell pressure and th...

p> Cette étude présente une analyse fréquentielle de la force radiale de Maxwell appliquée sur la surface interne du stator d'une machine synchrone à aimants permanents surfaciques (MSAP) à bobinage dentaire. Cette force radiale est le siège d'harmoniques spatio-temporels liés aux effets de la denture, de la saturation, de l'armature, des aimants i...

Nowadays, the development of the electric motorization for the land vehicles is essential since the energetic challenge is become very critical. Electrical machines dedicated to this operating segment have some specifics of torque characteristics (high saturation level, important flux weakening) over the speed range. This paper presents the develop...

Cet article porte sur les vibrations et le bruit acoustique d’origine magnétique (dû aux forces de Maxwell) dans les machines électriques tournantes synchrones (aimants permanents ou rotor bobiné - machines à réluctance variable exclues). Le phénomène de bruit magnétique y est analysé, et les différentes sources harmoniques d’efforts magnétiques so...

This paper presents an analysis of the radial Maxwell forces in the air gap of a concentrated winding for three-phase Permanent Magnet Synchronous Machine (PMSM). Many configurations are available with different windings or different topologies of stator-rotor. Radial forces versus time and spatial domains are the result of harmonics specific to th...

The work described in this paper deals with the analytical design and optimization of a line-start permanent magnet synchronous motor (LSPM) with a series magnetic circuit structure. The design approach considers a LSPM as an induction motor (IM) combined with a permanent magnet rotor arrangement and takes into account the characteristics of both a...

Modeling the dynamic behavior of electrical machines involves several fields of physics, such as electromagnetics, electronics, mechanics, thermodynamics and acoustics. Multi-physics lumped models are applied to an inverter-fed permanent magnet synchronous machine. These models are coupled and fully parameterized to optimize the machine for tractio...

Cet article porte sur les vibrations et le bruit acoustique d’origine magnétique (dû aux forces de Maxwell) dans les machines asynchrones. Les différentes sources d’efforts harmoniques y sont caractérisées analytiquement. Des outils de prédiction du niveau de bruit rayonné sont présentés, ainsi que différentes règles de conception. Enfin, des métho...

An optimized control strategy for induction machines is presented and compared to classic strategies. The described method allows to optimize voltage and frequency for a steady state equivalent circuit model of three-phase induction machine. This method is applied to an electric vehicle by simulating driving cycles and calculating energy consumptio...

This paper presents the full analysis of the radial forces behavior responsible for audible magnetic noise in a
PWM-fed permanent magnet synchronous traction machine with surface permanent magnet. Magnetic force waves due to slotting harmonics, pulse-width modulation (PWM) are characterized for different speeds, Including theoretical predictions an...

This paper describes the modeling of a permanent magnet synchronous machine (PMSM) by using lumped models (LMs). Designing electrical machines necessarily involves several fields of physics, such as electromagnetics, thermics, mechanics, and acoustics. Magnetic, electrical, electronic, and thermal parts are represented by LMs, whereas vibro-acousti...

This paper compares two rotor topologies of permanent magnet synchronous machines about the level and the origin of electromagnetic noise. The aim is to establish the origin of these radial forces: PM field, armature reaction or slotting harmonics. The first rotor has surface permanent magnet (SPM) and the second one has internal permanent magnet (...

This paper compares two rotor topologies of permanent magnet synchronous machines about the level and the origin of electromagnetic noise. The aim is to establish the origin of these radial forces: PM field, armature reaction or slotting harmonics. The first rotor has surface permanent magnet (SPM) and the second one has internal permanent magnet (...

This paper describes the modeling of a permanent magnet synchronous machine by lumped models. Several fields of physics, such as electromagnetics, thermics, mechanics and acoustics are necessary for designing electrical machines. The aim of this study is to build a design model of a permanent magnet synchronous machine for traction applications whi...

Nowadays, power converters in the railway indus- tries are increasingly more compact and powerful. This progress is due to the use of fast and efficient components capable of working at high frequency such as IGBT. However, this evolution leads to a considerable loss of harmonics in transformers and complicates their design. Moreover, the mean time...

Squirrel cage induction motors design requires making numerous trade-offs, especially between its audible electromagnetic noise level, its efficiency and its material cost. However, adding the vibro-acoustic and thermal models to the usual electrical model of the motor drastically increases the simulation time. A finite element approach is then inc...

RESUME – Cet article présente des résultats de simulations vibro-acoustique pour une machine à bobinage dentaire 10 pôles / 12 encoches équipée d'un rotor SPM (Surface Permanent Magnet). La machine répond à un cahier des charges type traction électrique. L'analyse du bruit d'origine électromagnétique, qui est pertinente pour des basses vitesses, de...

In order to optimize the design of an enclosed induction machine of railway traction, a multi-physical model is developed taking into account electromagnetic, mechanical and thermal-flow phenomena. The electromagnetic model is based on analytical formulations and allows calculating the losses. The thermal-flow modeling is based on an equivalent the...

This paper presents a fully analytical model of the electromagnetic and vibro-acoustic behavior of variable-speed squirrel-cage induction machines. This model is integrated in a fast simulation tool that can be used to design motors with low magnetic noise levels on their whole speed range. Some simulation results at variable speed are favorably co...

Acoustics comfort is an increasingly important factor at the design stage of industrial inductors associated to converters. In addition, power converters in railway domain are more and more compact and powerful. That is why the lumped models for the electromagnetic, thermic and vibro-acoustic parts are developed. This aim of this paper is to detail...

The design of variable-speed electrical machines involves several fields of physics, such as electromagnetism, thermics, mechanics, and also acoustics. This paper describes the analytical multiphysics models of a computer-aided-design software which is applied to inverter-fed traction induction machines. The electromagnetic model computes rotor and...

This paper derives the analytical characterization of the Maxwell radial vibrations due to pulsewidth modulation (PWM) supply in induction machines and, particularly, in traction motors supplied with an asynchronous switching frequency. The number of nodes and the velocity of these particular force waves are experimentally validated by visualizing...

The Maxwell pressure is the cause of stator deflection at the origin of acoustic noise radiated by stator. That is why precise determination of air-gap radial flux density Bg is of prime importance. It could be obtained by finite element method, semi numerical or totally analytic method with computation of magneto motive force and permeance. Slot n...

This paper presents a method to characterize the main magnetic force waves occurring in a sinusoidally fed induction machine. Three main force types are identified: slotting force waves, winding force waves, and saturation force waves. Slotting force waves are characterized in terms of number of nodes, velocity, propagation direction, and magnitude...

Although many empirical rules have been established for correctly choosing the number of stator and rotor slots so as to limit the audible magnetic noise level radiated by induction machines, these rules never take into account the stator natural frequencies or the fact that the motor is run at variable speed. In this paper, we present a fast simul...

This paper first presents the analytical models of an ALSTOM simulation software, DIVA, which computes the vibratory and acoustic behavior of a variable-speed induction machine due to Maxwell forces. This radial magnetic pressure in the air-gap makes the stator vibrate in the audible range, creating the so-called magnetic noise characterized by a h...

The authors present the full analysis of the vibration behaviour responsible for audible magnetic noise in a pulse-width modulation (PWM)-fed fractional-slot induction machine, including theoretical predictions, numerical simulations and experimental validations (stator modal analysis and deflection shapes visualisation). Magnetic force waves cause...