Fiche individuelle

The energy sources in a Hybrid Energy Storage System are coupled by a DC–DC converter. Nevertheless, this device’s mass is irrelevant when evaluating the performance of such a system in terms of density, so it must be reduced to achieve maximum performance. This can be achieved with the solution presented in this paper: a coupling architecture based on a controlled current source, in which the DC–DC converter’s processed power depends on the voltage difference between the two sources. If this difference is zero, so is the power processed by the converter. Minimizing this power leads to a reduction of the converter’s mass and volume, increasing system performance. In this paper, the controlled current source cascade architecture combines two lithium-ion batteries to supply a limited-range electric vehicle. Its operation is addressed and validated by simulation and experimental results. For the experimental validation, the batteries and the load were emulated by power supplies, with a 2 kg, 3.3 kW evaluation board serving as DC–DC converter. The findings reveal that the examined architecture enables a substantial reduction in the converter’s sizing power, up to a factor of 14 compared to a conventional solution commonly seen in the literature.

A Hybrid Energy Storage System (HESS) uses DC-DC converters to couple its energy sources. However, this device represents a "dead weight" in the system and must be reduced to a minimum in order to maximize the HESS' performance. This work proposes a new coupling architecture to reduce the converter's volume and mass. Not yet addressed in the literature, this architecture is based on a series coupling of the sources. In this case, a DC-DC converter is used to control the current difference between the two sources. If this difference is zero, so is the power processed by the converter. By reducing the power processed by the converter, its mass and volume can be reduced. Simulation and experimental tests were carried out to validate the architecture concept. For the latter, power supplies were used to emulate the batteries and the load, and a 2 kg, 3.3 kW evaluation board served as the DC-DC converter. The results show that, compared to a conventional solution that is usually adopted in the literature, with the series architecture, it is possible to reduce the converter sizing power by almost 3.7.

One of the main technological stumbling blocks in the field of environmentally friendly vehicles is related to the energy storage system. It is in this regard that car manufacturers are mobilizing to improve battery technologies and to accurately predict their behavior. The work proposed in this paper deals with the advanced electro-thermal modeling of a hybrid energy storage system integrating Lithium-ion batteries and supercapacitors. The objective is to allow the aging aspects of the components of this system to be taken into account. The development of a model including the electro-thermal behaviors makes it possible to evaluate the progressive degradation of the performance of the hybrid energy storage system. The characterization of both components constituting the hybrid system is carried out via a hybrid Particle Swarm–Nelder–Mead (PSO–NM) optimization algorithm using the experimental data of an urban electric vehicle. The obtained results show the good performance of the developed model and confirm the feasibility of our approach. The use of the PSO–NM optimization algorithm facilitated the identification of the parameters of the developed model with high efficiency, as the error observed is less than 3%. The advanced model associated with an adapted sizing method can be used in many cases to compare energy management strategies in electric vehicle applications.

The paper deals with electro-thermal modeling lithium-ion batteries. The model computes losses distrubution distribution to allow an accurate temperature distribution. The electrical model is updated through the mean temperature of the battery to insure an accurate estimation of losses at any temperature. The obtained results show that the proposed model is able to simulate the dynamic interaction between the electric and the thermal battery behavior, and high performance for the cell surface temperature prediction.

In this paper, a dynamic model of Li-ion batteries incorporating electrothermal and ageing aspects is proposed for electric vehicle applications. The main goal of the proposed model is to be both simple and sufficiently representative of the physical phenomena occurring in a battery cell. These two features allow for using this model as an evaluation tool of electric vehicle performances under different operational and environmental conditions. The developed model is based on an equivalent circuit diagram coupled with a thermal circuit and a semi-empirical ageing equation. Identification of parameters in the dynamic model is conducted by measurement tests in time-domain, which uses a hybrid Particle Swarm–Nelder–Mead optimization algorithm to achieve excellent prediction over the whole applicable current and state of charge ranges. The validation results show that the proposed model is able to simulate the dynamic interaction between the battery ageing and the thermal as well as electric behavior with sufficient accuracy in the range tested.

Modeling dynamic behaviors of the Li-ion battery and supercapacitor in electric vehicle applications is a key aspect for the emulation of the hybrid power supply. In this paper, a dynamical model based on two nonlinear equivalent circuits is developed to describe the characteristics of the battery and supercapacitor during both steady-state and transient conditions. The necessary parameters for proposed model are extracted from measurement data in time and frequency-domain using an optimization algorithm. The developed model is coupled to power electronics devices fed by DC power supply to carry out a laboratory emulator of the hybrid power supply. This tool is mainly used for testing and verification of the electric vehicle performances with convenient and reproducible way. The proposed emulator avoids time-consuming preconditioning and safety problems generally caused by the misuse of electrochemical components such as the Li-ion battery. The modeling and experimental results show a good performance of the hybrid power supply emulator and confirm their feasibility over a wide range of operating points.

Combining a high power source like a supercapacitor with a Li-ion battery for electric vehicle applications results in good performance improvements, highly efficient, long lifetime, lightweight design and relatively modest cost of the overall source. A hybrid energy storage system controlled by a smart energy management strategy can play a key role in the design and development of multi-source electric vehicles. In this work, an optimal energy management strategy based on particle swarm optimization incorporating Nelder-Mead simplex method is proposed. The goal of the proposed strategy is to minimize the battery power stress and improves its lifetime. This is achieved by coupling a rule-based method based on the knowledge of the battery and supercapacitor efficiency operating with a hybrid Particle Swarm–Nelder–Mead (PSO–NM) optimization algorithm. This latter approach is proposed to optimize the control parameters of the rule-based energy management strategy, once the off-line optimization algorithm is over, the control method can be implemented on-line. The obtained results demonstrate significant lifetime enhancements for Li-Ion battery, an increase of up to 20% as compared to the mono-source based on regular single battery.

Currently, the vehicle manufacturers use the high power Li-ion technology to supply the electric and hybrid vehicles. This technology is able to ensure the power needed to propel the vehicle. Until now several studies have been made by the laboratories and manufacturers to characterize this technology. The aim of these test (electric, thermal, aging,…) is to make comparison between Li-ion technologies and choice the best one for each application. For that, they use accelerated cycling with different condition to characterize cells, what can reduce the tests duration. Unfortunately, this type of cycle can’t give us information about the aging of HP Li-ion technology under real use of the vehicle. Firstly, the requirements specification (vehicle specification, battery technologies, mission) has been presented. After that, we will present the test bench developed in our laboratory to characterize batteries and study the aging of the HP technology. In this paper we present the study of the Li-ion HP behavior during almost 3 years and the modelling (electric, thermal and aging modelling) using a real driving cycle. The experimental results are compared to the results obtained with the developed ageing model. The obtained results prove the good performances of this technology in electric vehicle applications.

This paper examines and optimizes parameters that affect the sizing and control of a hybrid embedded power supply composed of Li-ion batteries and supercapacitors in electric vehicle applications. High demands including power and energy density, low charge/discharge power stress on the battery (long lifetime), lightweight design and relatively modest cost at the same time cannot be provided solely by batteries or supercapacitors. For this reason, we propose the use of a Li-ion battery/supercapacitor hybrid embedded power supply for an urban electric vehicle. The sizing process of this system including the optimization of the power sharing is done thanks to a developed hybrid Particle Swarm–Nelder–Mead (PSO–NM) algorithm involving multi-objective optimization. This approach also allows us to optimize the proposed energy management strategies based on frequency rule-based control and different ways of supercapacitors energy regulation. Obtained results show that the hybrid embedded power supply with the proposed control strategies is able to offer the best performances for the chosen electric vehicle in terms of weight, initial cost and battery lifetime.

In recent years, Li-ion batteries are widely used in various applications, such as electric and hybrid vehicles application. Their higher specific power and energy density, high cycle lifetime and decreasing costs have made them an attractive and alternative energy storage technology to lead-acid or nickel- metal hydride batteries in embedded power supplies. In the present work, the electric modeling of a Li-ion battery cell in real operating conditions imposed by an electric vehicle application is carried out. A dynamic equivalent circuit model has been used to simulate several electrochemical processes occurring in a commercially available 40 Ah Li-ion battery cell with NMC cathode material and graphitic anode. The model is parameterized with measurement data in time-domain using a hybrid Particle Swarm–Nelder–Mead (PSO–NM) optimization algorithm. This last one is used to solve the parameters identification problem of Li-ion battery model. The developed model of Li-ion battery cell has been validated on real driving cycle provided by an urban electric vehicle. Obtained results show that there is a good match between experiment and simulation results with a maximum modeling error less than 0.5%, which proves the well performance of our model and confirm the interest of a hybrid (PSO–NM) optimization algorithm for battery identification parameters.

Modern controlled electric drive applications, such as lifts, port rubber tyred gantry cranes, and tooling machines, are characterized by high ratio of the peak to average power. Moreover, such applications have a need for braking at rated power. In ordinary drives, the braking energy, which represents 30%–40% of the consumed energy, is dissipated on a brake resistor. Apart from this “energetic” issue, the mains interruption, the input current quality, and the mains peak power are additional issues to be addressed. A novel ultracapacitor-based controlled regenerative electric drive with peak power-smoothing function is presented in this paper. The ultracapacitor with an interconnection dc–dc converter is used to store and recover the braking energy. In addition, the dc–dc converter controls and smooths the rectifier input power. In comparison to state-of-the-art solutions, the new solution has better performance regarding size, cost, and efficiency. The presented solution is theoretically analyzed and experimentally verified. The results are presented and discussed.

In this paper, a study of the supercapacitors’ ageing process is presented. The originality of this work is that the tests are made under conditions similar to those of an industrial application. A continuous cycling is applied in order to obtain these test conditions. The measurement is done thanks to a test bench developed in our laboratory. More than 560,000 cycles have already been done, which corresponds to 325 cumulated days of continuous cycling. These tests allow to understand the ageing process of supercapacitors and to follow the evolution of theirs characteristics during their lifetime. The aim of this work is to study the behavior of the cells which compose the supercapacitors module (48V/ 112F).

Most of modern controlled electric drive applications, such as lifts, cranes, and tooling machines, are characterized by a high ratio of the peak to average power. In addition, such applications have high demand for braking at the full rated power. In ordinary drives, the braking energy, which represents 30%–50% of the consumed energy, is dissipated on a brake resistor. Apart from this “energetic” issue, power supply interruption and the input current quality are two additional issues to be solved. A novel regenerative controlled electric drive based on an ultracapacitor as energy storage is presented in this paper. The ultracapacitor with an interface dc–dc converter is used to store and recover the braking energy. In addition, the dc–dc converter controls the rectifier current and reduces the drive input current total-harmonic- distortion factor down to 30%. Moreover, the dc bus voltage is boosted and controlled to be constant and ripple free regardless of the load and the mains voltage variation. In comparison to state-of-the-art solutions, the new solution has better performance regarding size, cost, and efficiency. The presented solution is theoretically analyzed and experimentally verified. The results are presented and discussed.

Two issues are still a great challenge in design and application of advanced controlled electric drives, namely recovery of the braking energy and ride-through capability of the drive system. Apart from the ordinary solutions, such as back to back and matrix converters, an approach based on the ordinary diode front-end drive converter equipped with an energy storage element is used in some applications, such as traction and lift drives. This approach becomes in the focus recently with rapid development of electrochemical double layer capacitors (EDLC), so-called ultra-capacitors. To achieve the system flexibility and better efficiency, the ultra-capacitor is connected to the drive via a dc-dc converter. The converter is controlled in such a way to fulfil the control objective; control of the dc bus voltage, the ultra-capacitor state of the charge and peak power filtering. In this paper, we have presented modelling and control aspects of the regenerative controlled electric drive using the ultracapacitor as energy storage and emergency power supply device. The presented model and control scheme have been verified by Matlab/Simulink simulation. The presented concept was experimentally verified on a 5.5kW prototype. The results are presented and discussed in this paper.

Two issues are still a great challenge in design and application of advanced controlled electric drives: 1) recovery of the braking energy, and 2) ride-through capability of the drive system. Apart from ordinary solutions, such as back to back and matrix converters, the ordinary drive converter equipped with an energy storage element is used in specific applications such as traction and lift drives. This approach became in the focus recently with rapid development of electrochemical double layer capacitors (EDLC), so-called ultra-capacitors. The ultracapacitor is an electro-chemical capacitor having energy density much greater than that of standard electrolytic capacitors. Additionally, the ultra-capacitor power density is much higher than that of the existing electro-chemical batteries. In this paper, a regenerative controlled electric drive having extended ridethrough capability is discussed. Basic principle has been extensively analysed, including detailed analysis of all operational modes. A bi-directional three-level dc-dc converter has been considered as the interface power converter. The ultracapacitor design guide line is given. A control algorithm that allows control of the dc bus voltage and the ultra-capacitor voltage and current has been presented and briefly analysed. Regenerative controlled drive system has been tested and the results presented and discussed.

Electrochemical double-layer capacitors, which are well known as ultracapacitors, have intensively been used in power conversion applications such as controlled electric drives, active filters, power conditioners, and uninterruptible power supplies. The ultracapacitor is employed as the energy storage device that can be fully charged/discharged within a few seconds. To achieve better flexibility and efficiency, the ultracapacitor is connected to the power conversion system via an interfacing dc–dc power converter. Various topologies are used as the dc–dc power converter: nonisolated two-level single-phase or multiphase interleaved converters and many varieties of isolated soft-switched dc–dc converters. A three-level nonisolated dc–dc converter as a candidate for ultracapacitor applications is proposed and analyzed in this paper. The topology is theoretically analyzed, and design guidelines are given. The modeling and control aspects are discussed. A 5.5-kW prototype was designed, and the proposed topology was experimentally verified on a general-purpose controlled electric drive. Experimental results are presented and discussed.

Depuis quelques années le marché des supercondensateurs de forte puissance est en pleine émergence. Ces composants permettent de stocker une énergie conséquente et surtout de l’emmagasiner et de la restituer très rapidement (les courants de charge et décharge peuvent atteindre 500 A). Mais le faible niveau de tension que supportent ces éléments (2 à 3 V) impose de les associer en série, entraînant divers problèmes de fiabilité et de durée de vie. Dans cet article, une étude de caractérisation d’un module supercondensateur 100 F/56 V constitué de 28 éléments 2700 F/2,3 V est proposée. Cette étude permet de mettre en évidence les phénomènes de dispersion de tension des supercondensateurs. Ce travail de caractérisation a pour objectif d’une part de procéder au cyclage de ces modules dans le but de connaître l’évolution de leurs performances tout au long de leur vie, et d’autre part d’acquérir un savoirfaire dans ce domaine afin de mieux connaître ces composants en termes de performances et également en termes de contraintes technologiques.

Recent studies have shown that the use of battery-battery coupling in Hybrid Energy Storage Systems (HESS) presents advantages in terms of mass, volume and cost when compared to the battery-supercapacitor coupling. However, the sizing of this type of system is not much studied in the literature. So, in this paper a graphical sizing method using Ragone plots is presented. With this method, a HESS perfectly suited to a given application can be obtained.

When analyzing the characteristics of a Hybrid Energy Storage System in a Ragone plot, it can be seen that the mass of the necessary power electronics has a great influence on the system’s performance. Although many coupling architectures have been studied so far, the size of the power converter is not usually a priority. So, in this paper, a low-volume and high-efficiency converter is proposed. Placed in series between the sources, the converter depends only on the voltage difference between them. In this way, the converter can be reduced, since it does not manage the total power supplied by the accumulators, as a classic converter.

The association of more than one storage system to ensure the supplying of the hybrid and electric vehicle became more and more useful by the cars manufacturers. The asked question in this case is the optimal amount of the deferent energy sources to ensure the mission with the best lifetime. The first parameter witch influence the architecture of the hybrid storage system is the required autonomy. This paper deals with the choice of the architecture and the sizing of the hybrid source composed with battery and supercapacitor packs according to the desired autonomy. In this case, two technologies of Li-ion battery (power and energetic technologies) are associated with the supercapacitor. The obtained result about the size and the ageing of the source will be compared to that obtained using only power technology of Li-ion battery to supply the vehicle.

For hybrid and electric vehicle, high powers are needed for the acceleration, startup and recovery phases. For that, the chosen storage system must insure these high powers. The supercapacitors are powerful storage systems, which can reach more than 4,3kW/kg of specific power, and very high lifetime compared to the other storage components. Until 1957 five generations of supercapacitors are developed by the researcher in the entire world. The deference between these generations depends to the materials used for the electrode and/or the type of electrolyte solution. The use of deferent materials influences directly the behavior of the technology in term of specific power, specific energy, maximum voltage, maximum current and the lifetime. Currently, the manufacturer uses in 90% of the cases the technology with carbon electrodes and acetonitrile like electrolyte. This technology has a high specific energy and good lifetime. On the other hand, this technology is toxic and cheaper compared to the other ones. The aqueous technology can give us the solution for this problem, because of the no-toxicity of the electrolyte and the very high power of this component. Unfortunately, this technology has low specific energy because of the voltage limitation (maximum 1V). This paper deals with the comparison between the two technologies of supercapacitors (carbon electrode + organic electrolyte and carbon electrode + aqueous electrolyte). The characterization and the variation of the ageing of the two technologies according to the number of cycles will be presented.

Currently, the automakers use Lithium-ion battery like an energy storage system for vehicle propulsion. However the battery power is limited by two deferent rates of charge and discharge, what can limit the recovered energy during the brake phase. On the other hand, the supercapacitor is a powerful component which can deliver very high power pulse for the both charging and discharging phases. This paper describes a methodology for designing hybrid supply using Li-ion Batteries and supercapacitors for electric vehicle application taking in the account the energetic characteristics and powers limitations of battery and supercapacitor. The method developed in this paper allows us to estimate the optimal level of hybridization and gives us the best technologies to operate this hybridization. An example which illustrates these ideas is proposed and the sizing results of available energy using a hybrid supply are compared with those obtained using the battery like vehicle supply

Les sources de stockage hybrides (HESS) utilisent des convertisseurs DC-DC pour assurer le couplage des sources d'énergie. Pour des applications où l’espace disponible pour embarquer la batterie est limité, le volume et la masse de l’électronique de puissance doivent être réduites au maximum. C’est le cas des véhicules électriques. Dans ce travail, une nouvelle architecture de couplage permettant de réduire le volume et la masse du convertisseur est proposée. Cette architecture, basée sur un couplage en série des sources, est comparée aux solutions classiques. Elle permet de réduire très fortement la puissance de dimensionnement de l’électronique de puissance du HESS.

L'un des principaux verrous technologiques dans le domaine des véhicules propres est lié à la source de stockage de l'énergie électrique. C’est dans ce contexte que les constructeurs se mobilisent pour améliorer les technologies de batteries et pour prédire précisément leurs comportements. Le travail proposé ici traite de la modélisation de sources de stockage hybrides composées d'une association batterie lithium-ion et supercondensateurs. L'objectif est de permettre la prise en compte du vieillissement des composants de ce système. Le développement d'un modèle incluant les aspect électrique et thermique permet d'évaluer la dégradation progressive des performances des sources du système. Les résultats de simulation montrent les performances du modèle actif pour une source hybride et confirment la faisabilité de notre démarche. L'outil ainsi développé est destiné à comparer les méthodes de gestion des sources dans un système de stockage hybride mais également à en développer de nouvelles en intégrant le paramètre de durée de vie pour la conception de ces systèmes.

La présente invention concerne un dispositif d'alimentation d’un réseau électrique d'un véhicule automobile comprenant une première et une deuxième batterie et un convertisseur de tension continue comprenant une première borne reliée à la première batterie et une deuxième borne reliée à la deuxième batterie, la deuxième borne étant également destinée à être connectée au réseau électrique, dans lequel le convertisseur de tension continue est configuré pour réaliser une source de courant disposée en série entre la première et la deuxième batterie de façon à contrôler le courant échangé avec la première batterie.

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