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International audience; The energy consumption of electric vehicles depends on the traction energy but also on the thermal comfort energy. Some studies lead to the estimation of this energy consumption from real measurements on different driving and climatic conditions. However, those results rely on a large number of vehicle tests, which is time consuming. Moreover, the impacts of the different subsystems cannot be differentiated in such global studies. A flexible simulation tool can help to analyze the impact of the different parts of a vehicle. This paper proposes a multi-physical parametrized model of an electric vehicle including the traction and comfort subsystems. A flexible model of a Renault Zoe is developed thanks to the energetic macroscopic representation. This model is validated by experimental tests of the real vehicle. Then, the impact of the HVAC (heating, ventilation, and air conditioning) subsystem is studied for different driving cycles and climatic conditions. In very cold conditions, the use of the HVAC subsystem represents an increase of up to 248% of the total energy consumption, compared to summer conditions.

International audience; A carbon care action has been developed for a European research project focused on the development of greener vehicles. The aim of this action is to reduce and mitigate the greenhouse gases emissions due the project activities. The classical carbon assessment has been extended to consider all the activities of an international research project. For the 3.5 years project, 209 tons of CO2eq have been estimated as GHG emissions. The most important part is related to the transport despite a significant reduction of travel during the COVID-19 pandemic.; Une action Carbon Care a été menée dans le cadre d'un projet européen portant sur le développement de véhicules plus verts. L'objectif de cette action est de réduire et de compenser les émissions de gaz à effet de serre générées par les activités du projet. L'évaluation carbone classique a été étendue de façon à prendre en compte toutes les activités d'un projet de recherche international. Pour les 3,5 années du projet, les émissions de GES ont été estimées à 209 tonnes de CO2eq. La part la plus importante étant celle des transports malgré la réduction significative des voyages liée à la pandémie de Covid.

International audience; 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.

International audience

International audience; A new method is proposed in this paper to investigate the influence of current collapse effect on the Id-Vds characteristics of GaN-HEMTs in high voltage region based on a modified H-bridge circuit. The measured Id-Vds characteristics with and without the Vds bias are compared, which shows the effect of charge trapping due to the Vds bias on device Id-Vds characteristics in saturation region. These data will be used for a device model including the current collapse effect in full Id-Vds region.

International audience; In recent years, several works on grid-forming converters in transmission networks have been performed. Since these high voltage grids are mainly inductive, a natural decoupling exists between active and reactive power controls. This decoupling facilitates the design and the performance of the grid-forming controllers. However, in distribution applications, it is well known that the R/X ratio of the line impedance is substantially higher, preventing the system from a natural decoupling effect. This paper proposes an original solution to decouple the control and gives an application to a low voltage connection of a grid-forming converter.

National audience; Pressure ulcers are a concern not only for the patients who suffer from them, but also for public health. Its costs to the quality of life of patients and to the public finances can be reduced with an early diagnostic. Several efforts have been made to find a solution for this diagnostic, for example by analysing the hydration or the electrical impedance of the skin. So far, no method is sufficiently reliable. In this context, a low-frequency ultrasound device is proposed, with the aim of offering an alternative that can be reliable and non-invasive. The Langevin transducer is a highly efficient device that can provide a measurement of the mechanical characteristics of the skin. Initial results show that mechanical impedance can discriminate the skin according to the location of the measurement.; Les escarres représentent un problème sanitaire majeur non seulement pour les patients, mais aussi pour la santé publique. Ses couts pour la qualité de vie des patients et pour les finances publiques peuvent être réduits si son diagnostique se fait suffisamment tôt. Des nombreux efforts ont été faits en cherchant une solution pour ce diagnostique, en analysant l’hydratation ou l’impédance électrique de la peau, par exemple. Jusqu’à présent, aucune méthode n’est suffisamment fiable. Dans ce contexte, un dispositif de mesure d’impédance mécanique de la peau, utilisant des ultrasons de “basse fréquence”, est proposé, avec le but d’offrir une alternative qui peut-être fiable et non-invasive. Dans ce travail, nous proposons d’utiliser un transducteur de Langevin pour fournir une mesure des caractéristiques mécaniques de la peau. Des premiers résultats obtenus montrent que l’impédance mécanique permet de discriminer la peau selon la localisation de la mesure.

International audience; Convolutional neural networks (CNN) have shown great potentials and have been proven to be an effective tool for some image-based deep learning tasks in the field of computational electromagnetism (CEM). In this work, an energy-based physics-informed neural network (EPINN) is proposed for low-frequency electromagnetic computation. Two different physics-informed loss functions are designed. To help the network focus on the region of interest instead of computing the whole domain on average, the magnetic energy norm error loss function is proposed. Besides, the methodology of energy minimization is integrated into the CNN by introducing the magnetic energy error loss function. It is observed that the introduction of the physics-informed loss functions improved the accuracy of the network with the same architecture and database. Meanwhile, these changes also cause the network to be more sensitive to some hyperparameters and makes the training process oscillate or even diverge. To address this issue, the sensitivity of the network hyperparameters for both physics-informed loss functions are further investigated. Numerical experiments demonstrate that the proposed approaches have good accuracy and efficiency with fine-tuned hyperparameters. Furthermore, the post-test illustrates that the EPINN has excellent interpolation performance and can obtain good extrapolation results under certain restrictions.

International audience; This work presents the control of a piezoelectric interface that combines two vibration modes of a plate to render the haptic feeling of a button click. By principle, the two vibration modes create an elliptical motion of particles of a beam that can induce a lateral force to the fingerpulp. In this device, the synchronization of the modes’ vibrations is essential, and can be obtained with a closed loop control. In the paper, we present the control in the (d,q) frame, because it can ensure the dynamic performances to achieve a compelling haptic feedback, yet being robust besides the external disturbances produced by the user’s finger. The proposed method could achieve a 2 ms response time, and the haptic feedback was perceived by 100% of users in a psychophysical study.

International audience; Carbon assessment is beginning to be widely used in research. It is used to quantify the amount of Greenhouse gases (GHG) emissions of an activity and even tend to be part of the indicators that serve to evaluate labs. Databases and tools are available. Methods as well but they have to be adapted to each case, depending on the activities of the organization or company to be studied and the way people in charge want to build their assessment. This article aims at proposing a method for the assessment of GHG emissions of research projects. Being organized around the different activities within a research project, this method takes into account all aspects of the project. It allows a good picture and analysis of GHG emissions linked to a project.

International audience; 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.

International audience; The aim of this paper is to validate the compliance between an EV and a battery with a reference driving cycle. The Hardware in the Loop methodology is used. It is based on the interactions between the different EV subsystems. In this paper, a 35 kWh battery pack is studied. A 5 kWh module from this pack is tested with the same power constraints when used in the real EV. The developed power Hardware-in-the-Loop (HiL) test bench is composed of a model of the traction chain and a controllable current source. A driving velocity cycle is used as an input. The HiL test is achieved at full power scale for a module. It is shown that the tested battery could be used in the studied EV as the limits of the battery operation are not crossed for a WLTC velocity cycle.

International audience; The growth of X-in-the-Loop (XiL) testing has been accompanied by a rapid growth in tools tailored for testing. While this increases the accessibility of tools for various specific applications, using multiple model and testing softwares can introduce compatibility issues when performing tests in the integration stage. This article provides a demonstration framework of a flexible Hardware-in-the-Loop (HiL) interface utilizing both Typhoon HIL and SIEMENS Amesim software and hardware for full vehicle emulation. First demonstrations of these HiL interfaces for a Plug-in Hybrid Electric Vehicle (PHEV) are shown. Flexible HiL interfaces such as these represent a much easier way to integrate full vehicle models within existing vehicle development frameworks.

International audience; Retrofit electrification of engine-powered vehicles to plug-in hybrid electric vehicles is growing. Different hybrid solutions exist, but all of them must compromise between integration constraints, cost and efficiency. Full vehicle simulation, including the powertrain subsystems is thus mandatory. During the pre-design step, some sub-systems are not available. Use a simplified model for some subsystems is then common, to initiate the sizing process. In this paper, two electric drive models are compared: one using a torque and speed dependent loss map and another with a constant efficiency. Using Dynamic Programming, the fuel consumption is estimated for both models. The simple average efficiency leads to only 3% of errors on fuel saving. Such simple model can thus be relevant for the comparison of solutions in terms of fuel saving.

International audience; The commuting home-work trips is an important contributor of the Greenhouses Gases (GHG) emissions of cities. In the campus “cité scientifique” of University of Lille, the commuting trips represent more than 50% of the total GHG emission. But during the pandemic, working at home change lead to significantly reduce these daily trips. At first sight, teleworking seems a valuable mean to cut these emissions by working at home and avoiding home-work trips. However, it requires new tools, such as videoconference, which also lead to indirect GHG emissions. In this paper, the GHG of a small research group on electro-mobility has been analyzed before and during the lockdown. From this case study, the GHG benefit depends on the daily commuting distance and the transport mean. For example, a person with 10-km daily trip using subway will increase its GHG emission by teleworking.

International audience; Nowadays, the production of electric energy is evolving towards decentralized systems by an increasingly advanced integration of new active loads such as electric vehicles and renewable energy sources. This energy transition involves the use of power electronics converters to regulate energy exchanges. In this context, this paper brings the L2EP knowledge on grid-forming control developed in a high-voltage context to the ValeoSiemens reversible charger. This comprises two significant differences in the sizing of the system: a lower grid connection impedance and a resistive aspect of the distribution network. To overcome these challenges, this paper proposes two techniques: the virtual impedance to compensate the low value of connection impedance and dynamic decoupling of active and reactive power to consider the resistive effect of the distribution network.

As stricter regulations on air quality are imposed on automotive manufacturers, simulation is playing a more important role in the electric vehicles design and production. Virtual testing helps reduce the costs of assessing vehicle performances and flaws which can be corrected early on, before the real testing is begun. This paper presents the validation, using Simcenter Amesim, of a virtual battery electric vehicle model with real measured data from the real Renault Zoe vehicle on track. The validated models give confidence in future reuse for other virtual testing scenarios, allowing to perform the tests in the digital domain, early in the development cycle, without the need of expensive and time-consuming real testing platforms.

International audience; The study of skin mechanical impedance is a clue to analyse its health. We use a Langevin Transducer at 60kHz to excite the skin. In return we observe the acoustic forces generated by the interaction. To achieve that, the system is identified and presented in the rotating reference frame, and we describe the design of two PI controllers that accurately control the vibration velocity. However, in vivo analysis can be tricky when it comes to safety and duration of tests. Thus, phantom tissues are used as substitute to simulate skin behaviour. Due to its mechanical properties similar to skin, and its simple manipulation, Dragon Skin ®, a silicone rubber type of phantom, was chosen. The paper presents the characterisation of the mechanical impedance of three silicon phantoms with different properties based on force observation. The results show that the phantoms can be indeed identified based on this method.

International audience; The transformations of conventional Internal Combustion Engine (ICE)-powered vehicles into electrified vehicles are of growing interest. The retrofit hybridization of a Peugeot 308 SW passenger car is studied. For this purpose, a complete hybridization system is added to the rear axle of the vehicle. As a result, the control of the initial ICE-powered vehicle has to be updated. The aim of this paper is to deduce the potential fuel saving thanks to this hybridization. The simulation results show an energy saving of at least 9% and potential consump-tion reduction on a Worldwide harmonized Light-duty Vehi-cles Test Cycle (WLTC).

International audience; The automotive industry is shifting to mass production of electrified vehicles. Simulation is a key step for developing these new vehicles. System simulation tools as Simcenter Amesim includes ready-to-use multi-physics libraries in that perspective. A new library is being created based on the Energetic Macroscopic Representation formalism to speed-up the battery electric vehicles (BEV) development process. The paper presents the BEV multi-level simulation where the simulations were done using 3 different levels for the battery models. By using “plug & play” method different BEV model configurations can be built in a fast, precise and systematic way.

This paper studies the effect of the granularity of a cell model on the voltage accuracy. A multi-coupled cell model with varying parameters is compared with a simpler one (varying voltage source and equivalent series resistance). The first model implies a very long and complex characterization process. The second one is very simple. Experiments are performed at different temperatures by applying a current profile corresponding to a driving cycle of an electric vehicle. Experimental results show both models can be used for $25^{\circ}\mathrm{C}$ and $10^{\circ}\mathrm{C}$ ambient temperatures with reasonable accuracy. Nevertheless, when the temperature is cold the multi-coupled model is more accurate.

International audience; Optimization-based methods are of interest for developing energy management strategies due to their high performance for hybrid electric vehicles. However, these methods are often complicated and may require strong computational efforts, which can prevent them from real-world applications. This paper proposes a novel real-time optimization-based torque distribution strategy for a parallel hybrid truck. The strategy aims to minimize the engine fuel consumption while ensuring battery charge-sustaining by using linear quadratic regulation in a closed-loop control scheme. Furthermore, by reformulating the problem, the obtained strategy does not require the information of the engine efficiency map like the previous works in literature. The obtained strategy is simple, straightforward, and therefore easy to be implemented in real-time platforms. The proposed method is evaluated via simulation by comparison to dynamic programming as a benchmark. Furthermore, the real-time ability of the proposed strategy is experimentally validated by using power hardware-in-the-loop simulation.

International audience; Optimization using finite element analysis and the adjoint variable method to solve engineering problems appears in various application areas. However, to the best of the authors’ knowledge, there is a lack of detailed explanation on the implementation of the adjoint variable method in the context of electromagnetic modeling. This paper aimed to provide a detailed explanation of the method in the simplest possible general framework. Then, an extended explanation is offered in the context of electromagnetism. A discrete design methodology based on adjoint variables for magnetostatics was formulated, implemented, and verified. This comprehensive methodology supports both linear and nonlinear problems. The framework provides a general approach for performing a very efficient and discretely consistent sensitivity analysis for problems involving geometric and physical variables or any combination of the two. The accuracy of the implementation is demonstrated by independent verification based on an analytical test case and using the finite-difference method. The methodology was used to optimize the parameters of a superconducting energy storage device and a magnet press and the optimization of the topology of an electromagnet. The objective function of each problem was successfully decreased, and all constraints stipulated were met.

International audience; Despite their low environmental impact, electrical vehicles have low penetration in the automotive market. Consumers are reluctant for technical reasons (limited driving range and long charging time) but also for an economic reason (high investment costs). Electric vehicle total cost of ownership (TCO) is often perceived as higher than for a thermal car, especially in Europe where diesel cars have a lower TCO than gasoline cars. Accurate TCO estimations are critical, but most of the techno-economic studies of electrified vehicles are based on very simplified energy models. In this paper, a techno-economic model is developed using an accurate technical model of an electric vehicle and a diesel car of the same segment. These technical models are validated by experimental measurements on real cars using real driving cycles. These models are then coupled to economic models to calculate TCO for a French case study. The total cost of ownership of the studied electric car is lower than for the equivalent diesel car by about 1000¿ for a 5-year ownership period. Of particular importance is the finding that using real driving cycles instead of standard driving cycles decreases the TCO of electric cars while simultaneously increasing the TCO of diesel vehicles. This has implications for techno-economic models, suggesting that the typical TCO approach that uses manufacturer-reported standard cycle data may be systemically biased towards thermal vehicles. In order to understand how TCO may change in different locations, a sensitivity analysis varies different technical and economic factors. Government subsidy, ownership duration, and vehicle depreciation are the most important factors for the TCO of electric vehicles. However, TCO of the electric cars can be lower than the TCO of equivalent diesel cars under a wide range of reasonable inputs. INDEX TERMS Electric vehicle, diesel vehicle, life cycle cost, total cost of ownership, sensitivity analysis.

European Union (EU)Horizon 2020; International audience; The development of electric vehicles has been spectacular over the last 20 years, so the automotive industry has started to shift mass production of electrified vehicles. However, new electrified vehicles are required to face the needs of the users. Simulation is a key step for development of new vehicle. Organization tools, such as Energetic Macroscopic Representation (EMR), have therefore been developed to improve and speed-up the development of virtual electric vehicle models. The paper presents a comparison between functional and a structural representation on EV simulation under Simcenter Amesim. This paper studies the impact of the two representations on the simulation results and time. For this purpose, an EMR library for the Simcenter Amesim simulation tool has been developed.