Electric vehicle range and battery lifetime: a trade-off

32 nd Electric Vehicle Symposium (EVS32), LYON, FRANCE, 19-/05/2019 - 22/05/201

Aging aware adaptive control of Li-ion battery energy storage system for flexibility services provision

Battery energy storage systems (BESSs) play a major role as flexible energy resource (FER) in active network management (ANM) schemes by bridging gaps between non-concurrent renewable energy sources (RES)-based power generation and demand in the medium-voltage (MV) and low-voltage (LV) electricity distribution networks. However, Lithium-ion battery energy storage systems (Li-ion BESS) are prone to aging resulting in decreasing performance, particularly its reduced peak power output and capacity. BESS controllers when employed for providing technical ancillary i.e. flexibility services to distribution (e.g. through ANM) or transmission networks must be aware of changing battery characteristics due to aging. Particularly of importance is BESSs' peak power changes aiding in protection of the Li-ion BESS by restricting its operation limits of it for safety reasons and improving its lifetime in the long run. In this paper, firstly an architecture for ANM scheme is designed considering Li-ion BESSs as one of the FERs in an existing smart grid pilot (Sundom Smart Grid, SSG) in Vaasa, Finland. Further, Li-ion BESS controllers are designed to be adaptive in nature to include its aging characteristics, i.e. tracking the changing peak power as the aging parameter, when utilised for ANM operation in the power grid. Peak power capability of the Li-ion nickel‑manganese‑cobalt (NMC) chemistry-based battery cell has been calculated with the experimental data gathered from accelerated aging tests performed in the laboratory. Impact of such aging aware and adaptive Li-ion BESS controllers on the flexibility services provision for power system operators needs will be analysed by means of real-time simulation studies in an existing SSG pilot./© 2022 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).fi=vertaisarvioitu|en=peerReviewed

Optimal Scheduling to Manage an Electric Bus Fleet Overnight Charging

Electro-mobility is increasing significantly in the urban public transport and continues to face important challenges. Electric bus fleets require high performance and extended longevity of lithium-ion battery at highly variable temperature and in different operating conditions. On the other hand, bus operators are more concerned about reducing operation and maintenance costs, which affects the battery aging cost and represents a significant economic parameter for the deployment of electric bus fleets. This paper introduces a methodological approach to manage overnight charging of an electric bus fleet. This approach identifies an optimal charging strategy that minimizes the battery aging cost (the cost of replacing the battery spread over the battery lifetime). The optimization constraints are related to the bus operating conditions, the electric vehicle supply equipment, and the power grid. The optimization evaluates the fitness function through the coupled modeling of electro-thermal and aging properties of lithium-ion batteries. Simulation results indicate a significant reduction in the battery capacity loss over 10 years of operation for the optimal charging strategy compared to three typical charging strategies

A quadratic programming based optimisation to manage electric bus fleet charging

The use of electric buses (EBs) is expected to increase significantly in the coming years. Uncontrolled charging of EBs can affect not only the power grid (grid instability, harmonic pollution...) but also the operating cost. This paper introduces an optimal charging strategy based on charging schedule planning and modulation of charging power for a fleet of electrically powered buses. The optimal charging strategy allows minimising the charging cost as well as the load power variations using quadratic programming. The proposed quadratic programming can significantly reduce the computation time and simultaneously handle a large bus fleet. First results indicate a significant reduction in customer energy bills while avoiding potential penalties due to peak loads.L'utilisation des bus électriques (BEs) devrait augmenter considérablement dans les années à venir. La charge incontrôlée des EBs peut affecter non seulement le réseau électrique (instabilité du réseau, pollution harmonique...) mais aussi le coût d'exploitation. Ce document présente une stratégie de recharge optimale basée sur la planification et la modulation de la puissance de la recharge d'une flotte de bus électriques. La stratégie de recharge optimale utilise la programmation quadratique afin de minimiser le coût de la recharge ainsi que la puissance efficace. La programmation quadratique proposée permet de gérer simultanément une grande flotte de bus électriques en un temps de calcul réduit. Les premiers résultats indiquent une réduction significative au niveau de la facture d'électricité ainsi qu'au niveau de la puissance nécessaire

Troublesome Heterotopic Ossification after Central Nervous System Damage: A Survey of 570 Surgeries

BACKGROUND: Heterotopic ossification (HO) is a frequent complication after central nervous system (CNS) damage but has seldom been studied. We aimed to investigate features of HO for the first time in a large sample and the rate of early recurrence of HO in terms of the time of surgery. METHODOLOGY/PRINCIPAL FINDINGS: We retrospectively analyzed data from an anonymous prospective survey of patients undergoing surgery between May 1993 and November 2009 in our institution for troublesome HO related to acquired neurological disease. Demographic and HO characteristics and neurological etiologies were recorded. For 357 consecutive patients, we collected data on 539 first surgeries for HO (129 surgeries for multiple sites). During the follow-up, recurrences requiring another surgery appeared in 31 cases (5.8% [31/539]; 95% confidence interval [CI]: 3.8%-7.8%; 27 patients). Most HO requiring surgery occurred after traumatic brain injury (199 patients [55.7%]), then spinal cord injury (86 [24.0%]), stroke (42 [11.8%]) and cerebral anoxia (30 [8.6%]). The hip was the primary site of HO (328 [60.9%]), then the elbow (115 [21.3%]), knee (77 [14.3%]) and shoulder (19 [3.5%]). For all patients, 181 of the surgeries were performed within the first year after the CNS damage, without recurrence of HO. Recurrence was not associated with etiology (p = 0.46), sex (p = 1.00), age at CNS damage (p = 0.2), multisite localization (p = 0.34), or delay to surgery (p = 0.7). CONCLUSIONS/SIGNIFICANCE: In patients with CNS damage, troublesome HO and recurrence occurs most frequently after traumatic brain injury and appears frequently in the hip and elbow. Early surgery for HO is not a factor of recurrence

Bilan environnemental des véhicules électriques

Journée de la mobilité électrique - AVERE Auvergne Rhône Alpes, VILLEURBANNE, FRANCE, 14-/11/2017

Actionneurs linéaires rapides

These systems generate a translational movement. They provide many ancillary but essential functions in variousmechanisms. An increasingly short response time is required, so we are all interested in the speed of these devices.The main families of linear electromagnetic actuators are presented with their static and dynamic characteristics accompanied by examples of applications.The study of the electromagnet type actuator has been more particularly developed.The influence of magnetic, electrical and geometric parameters on dynamic operation has been studied by numerical simulationand experimentally.General rules for the dimensioning of fast linear actuators conclude this study.Ces systèmes engendrent un mouvement de translation. Ils assurent de nombreuses fonctions annexes mais indispensables dans diversmécanismes. Un temps de réponse de plus en plus court est demandé, aussi nous sommes tous intéressés à la rapidité de ces dispositifs.Les principales familles d'actionneurs électromagnétiques linéaires sont présentées avec leurs caractéristiques statiques et dynamiques accompagnées d'exemples d'applications.L'étude de l'actionneur de type électroaimant a été plus particulièrement développée.L'influence des paramètres magnétiques, électriques et géométriques, sur le fonctionnement dynamique a été étudiée par simulation numériqueet expérimentalement.Des règles générale pour le dimensionnement d'actionneurs linéaires rapides concluent cette étude

Pourquoi la charge des véhicules électriques doit être intelligente ?

Journées thématiques "Trans-Cité" : La mobilité en Ile-de-France : regards croisés et défis à partager, VERSAILLES, FRANCE, 18-/05/2017

Stockage de l’énergie dans les applications Transports : Etat de l’art et perspectives sur les batteries et les supercondensateurs

National audienc

Caractérisation des usages de batteries Lithium-ion pour véhicules électriques ou hybrides. Application à l’étude du vieillissement et de la fiabilité

National audienc