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This article introduces the energetic macroscopic representation (EMR) as approach for the dynamic nonlinear modeling of a reciprocating air compressor. EMR has been introduced recently for research development in complex electromechanical systems. It is based on action reaction principle, which organizes the system as interconnected subsystems according to the integral causality. The graphical modeling based on EMR has advantages such as readability, modularity, structural and functional characteristics. The EMR is the first step toward model-based control structure development. The air compressor system containing: slider-crank mechanism, cylinder head and valves, is divided into multitude simple subsystems. Each subsystem describes an elementary step of the energy conversion, several of these blocks may occur in a single module. Calculations are carried out using two basic principles: mass and energy balances. Models are developed for different subsystems, which are assembled into a final overall system EMR. The EMR modeling presented here allows the modeling of multi-physics components and highlights the interactions of the electromechanical, thermodynamical, heat transfer and fluidic phenomena that occur simultaneously in an air compressor.

Cette contribution présente l’interface entre une source d’énergie faible puissance vers une application de puissance plus élevée, à fonctionnement intermittent. Dans le cas considéré, où la source de faible puissance est composée de cellules photovoltaïques, la chaîne d’adaptation de puissance est généralement constituée de plusieurs convertisseurs et d’un stockage tampon de type supercapacitif. Cette contribution introduit une solution qui permet de se passer du convertisseur de charge à recherche du point de puissance maximale (MPP). Basé sur cette première solution, un système d’adaptation de puissance bi-étagé est présenté. Les critères de dimensionnement y sont décrits, ainsi que des considérations sur les rendements des solutions envisagées.

In order to make electric vehicles more and more attractive, it is essential to improve the range flow rate1 under limited charging infrastructures. Therefore, a universal input and high power electric energy conversion will impose new requirements on power modules with respect to power loss, density, voltage / current ratings and transient as well as environmental conditions, specifications of lifetime and cost. In order to meet these requirements, the configurable electric vehicle (CEV) has been proposed. This paper is devoted to present the experimental validation of the concept and particular attention is paid to the failure mechanism and robustness challenges of power modules.

This article introduces the energetic macroscopic representation (EMR) as approach for the dynamic nonlinear modeling of a reciprocating air compressor. EMR has been introduced recently for research development in complex electromechanical systems. It is based on action reaction principle, which organizes the system as interconnected subsystems according to the integral causality. The graphical modeling based on EMR has advantages such as readability, modularity, structural and functional characteristics. The EMR is the first step toward model-based control structure development. The air compressor system containing: slider-crank mechanism, cylinder head and valves, is divided into multitude simple subsystems. Each subsystem describes an elementary step of the energy conversion, several of these blocks may occur in a single module. Calculations are carried out using two basic principles: mass and energy balances. Models are developed for different subsystems, which are assembled into a final overall system EMR. The EMR modeling presented here allows the modeling of multi-physics components and highlights the interactions of the electromechanical, thermodynamical, heat transfer and fluidic phenomena that occur simultaneously in an air compressor.

In the framework of the diversification of the electric vehicle charging standards, the configurable modular multilevel converters (CMMC) have been found as one of the best concepts for a universal and flexible charging system. It is foreseen that they include high power density, reliability and low cost. However, such a converter appears to induce a frequent charge-discharge cycling of the split integrated battery, which seems to have an influence on the battery aging. Therefore, this paper is devoted to present the experimental validation of the concept where particular attention is paid to the battery state of charge ripple induced by the frequent charge-discharge of the split batteries.

Today, energy saving is one of the main objectives for engineers. In the case of mobile applications, energy can be saved by two different ways: decreasing the total masse of the system and increasing the efficiency of the overall system. This paper presents two optimization strategies to design a predefined multichannel structure of a boost converter which is dedicated to a solar airplane and used to interface PV panels and the battery system. The first strategy is a multi-criterion method that is able to trace the dependency between the converter’s efficiency and its power density through the intermediary of the Pareto front. The second method, a mono-criterion approach, maximizes efficiency while respecting the constraint imposed on power density. The mono-criterion method that is applied to maximizing the European efficiency criterion showed that an increase in the number of channels enhanced the quantity of energy collected over a day by increasing the power density of the converter. At the end of the paper, the optimal design calculated was built to give an example of the result obtained by this design methodology. The results of the efficiency measurements made on a realized prototype are presented in this paper.

Accumulators are inserted on the DC bus of a conventional elevator, to increase its efficiency and limit the power demand on the main feeding grid. In the process that enable the identification of the control of such a system, The Energetic Macroscopic Representation methodology is defined and used to underline where conventional control is needed, and where more complex strategies are required. General comments are proposed, linked to energy management strategies, and promising experimental results are proposed.

les accélérateurs de particules sont des installations conçues pour recevoir des particules à basse énergie et les accélérer avant extraction. ils fonctionnent généralement en mode pulsé, ce qui entraîne des variations de puissance très élevées et très rapides. Pour réduire l’impact de ces dernières sur le réseau électrique, le CERN a développé en collaboration avec l’EPFL un système de puissance avec stockage d’énergie intégré.

This paper presents a modular control platform which is tailored for teaching and research applications. It aims at being entirely “student-proof” and features software-independent safety mechanisms, extensive signal conditioning and easy-to-use interfaces, dedicated to power electronics. A practical example with various HIL simulation results illustrates the attractiveness of the presented platform.

Bidirectional buffered units for Multiports charging of EV’s are presented, allowing to charge with high power even if the line current capability is limited. The systems are also dedicated to operate as reactive power compensators, or to provide grid system services as V2G operation or other power smoothing functions.

Regenerative braking is presented in many electric traction applications such as electric and hybrid vehicles, lifts and railway. The regenerated energy can be stored for future use, increasing the efficiency of the system. This paper outlines the benefits of the MMC (modular multilevel converter) in front of the cascaded or series connection of converters to achieve high voltage from low voltage storage elements such as supercapacitors. The paper compares three different solutions and shows that the MMC can benefit from weight and volume reduction of the output inductance when shifted switching modulation strategy is used. Using this modulation strategy, not only the output frequency is increased, but also the magnitude of the inductor applied voltage is reduced, reducing inductor size and volume.

The feeding device enables a charge (1) to be fed with relatively weak medium power on the one hand, and strong power points on the other, due to energy storage condensers (21) placed in a series. Each of said energy storage condensers (21) is linked to an DC/DC converter (20, 200), with control methods (5) being provided to equalize the power at the condenser terminals in addition to the power delivered by each one.

Today, there is a long-term trend towards bi-directional and flexible charger functions for not only drawing current from the grid but also feeding excess energy back into it. The Configurable Modular Multilevel Converter (CMMC) offers a large flexibility in order to handle the different voltage levels and current intensities in electric vehicle’s battery charging and discharging. Therefore, this paper is devoted to demonstrate the feasibility of the CMMC for Flexible Electric Vehicle (Flex-EV). It is a smart method to achieve a high power density and a compact power conversion for electric vehicles. The concept allows increasing the electric vehicle (EV) fault ride-through capabilities under damaged battery cells. It allows interfacing EV to worldwide charging infrastructures, meaning from standard household single phase socket to direct current (DC) ultra-fast charging stations. This concept is based on integration of the motor subsystem, the battery management subsystem as well as the universal and flexible charging subsystem. In fact, the power conversion consists of a modular multilevel converter (MMC) with split integrated storage (SIS) based on battery modules.

This paper presents new analytical equations, parametrized with respect to the number of converter phases, for multiphase isolated dc-dc topologies. This paper describes five multiphase isolated converter models, as well as their level of accuracy. Based on these new parametric models, a thorough comparative among various common high-power converter topologies is carried out, highlighting the best topology regarding efficiency, cost, and power density. The analytical results are firstly compared and verified using PLECS simulation software, and validated finally by experimental measurements with a 10-kW/20-kHz/500-V configurable laboratory prototype. Due to the low computation cost and accuracy, the developed analytical models provide important insights for optimization-based design methodologies. Furthermore, this paper highlights, depending on the targeted application and objectives, the benefits of each analyzed converter configuration.

Les récent progrès dans le demaine des matériaux supraconducteurs sont remarquables. Outre leur utilisation dans la science expérimentale, on peut prévoir que le demaine de la distribution et de l'utilisation de l'énergie életrique tirera un rand avantage de cette nouvelle technologie. Un dispositif utilisant de tels matériaux, un transformateur supraconducteur de distribution, a été mis en service récemment aux Services Industriels de Genève. Cet article décrit un aspect particulier de tels transformateurs et propose une solution aux problèmes posés lors de leur enclenchement.

A new feed-forward control technique for a DC-DC step-up converter based on the asymmetric Multistage Stacked Boost Architecture (MSBA) is proposed. The devel-oped feed-forward controller directly handles the load current and the perturbations that may be caused by the dynamic operation of the converter. Thus, there is no time delay for estimating the error in a control process and therefore, both robust steady-state operation and high dynamic performance can be achieved. The asymmetric MSBA DC-DC converter is a single output high-voltage topology that embodies several in-series active voltage balancing circuits. Thus, there is a need for an improved balancing control method. This can be ac-complished by replacing the conventional Proportional-Integral (PI) controllers with feed-forward type and therefore improved balancing between the stages can be attained, be-cause the steady state errors are suppressed and the dynamic response can be enhanced. A thorough theoretical analysis is conducted for verifying the stability of the suggested feed-forward control technique in an asymmetric MSBA converter and selective simulation and experimental results are demon-strated in order to validate the effectiveness and feasibility of the proposed control scheme.

The Multistage Stacked Boost Architecture (MSBA) is a non-isolated step-up converter topology intended for renewable energy generation systems or distribution networks. In previous papers the functionality and intended applications for this topology have been discussed ([1-3]); therefore this paper will concentrate on the Energetic Macroscopic Representation of the topology as well as a functional control and a working prototype. The Energetic Macroscopic Representation (EMR) is a graphical as well as functional description of an energetic system based on the physical causality. The EMR highlights the energetic properties of the subsystems of a whole system in order to deduce its control scheme in a systematic way [4-5].

To increase the appeal of electric vehicles, the trend is to shorten the charging time and to lengthen the autonomy. The new ultrafast charge compatible battery on lithium-titanate gives the best compromise between high power and energy densities. The main objective of the contribution is to demonstrate the state-of-the-art of the fast charged electric vehicles and propose an evaluation tool for determining the possibility of shortened charging times from the traction battery viewpoint.