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Le projet FOREVER a pour objectif d'évaluer l'impact des véhicules électriques et hybrides sur le bruit de trafic routier du réseau national. L'amélioration des performances des batteries a permis d'accroître l'autonomie des véhicules utilisant une propulsion électrique. Les véhicules électriques, développés à l'origine pour un usage urbain, sont désormais utilisés également en dehors des villes. De même les véhicules hybrides disposent d'une autonomie étendue en mode électrique. Cet article présente des résultats concernant les bruits émis par ces véhicules, à partir de méthodes de mesures appropriées (mesures normalisées "au passage" et imagerie acoustique). Les expérimentations ont été conduites sur piste d'essai en environnement maîtrisé. Les résultats portant sur quelques véhicules légers électriques et hybrides sont présentés. Différentes conditions de fonctionnement sont analysées : vitesse constante, accélération moyenne ou forte, décélération et freinage. Ces résultats sont ensuite comparés aux lois d'émission proposées par le modèle de prévision CNOSSOS-EU préconisé pour les évaluations environnementales et les cartes stratégiques de bruit en Europe. Une méthode corrective est proposée pour les véhicules électriques afin d'intégrer dans la méthode européenne la particularité de cette nouvelle motorisation.

Au-delà des zones urbaines, la part de véhicules électriques et de véhicules hybrides est en expansion dans le parc roulant sur les réseaux nationaux. Leur impact sonore dans ce contexte extra-urbain a été étudié dans le projet FOREVER, en considérant la contribution du bruit de propulsion et celle du bruit de roulement. Un modèle d'émission sonore adapté au véhicule électrique a été proposé pour la méthode européenne d'évaluation du bruit environnemental CNOSSOS-EU.

Electric and hybrid-electric vehicles are often referred to as quiet vehicles, comparatively to conventional internal combustion engine vehicles. At first, these new vehicle types were mainly developed for urban situations for their qualities concerning air pollution reduction, but due to the improvement of their electric range, they can also be encountered on national road networks. The electric and hybrid powertrain technologies are mostly employed on light vehicles, but a more recent breakthrough of electro-mobility can also be observed in heavier vehicles, such as delivery trucks or buses. In the framework of the project FOREVER, supported within the CEDR-TRRP programme and which primarily aims to provide data and information on the potential future noise impacts of electric vehicles on national roads, noise emission levels from several electric and hybrid-electric vehicles have been investigated. Measurements carried out on an experimental test track covered with dense asphalt concrete included microphones at the standard position (distance 7.5 m and height 1.2 m) and a wide range of driving conditions (constant speed, acceleration, deceleration and braking) and vehicle speeds. The dataset has been completed with results already available by project partners. Global and frequency dependent results have been compared with the sound emission model provided in CNOSSOS-EU. When appropriate, an adaptation of CNOSSOS-EU input data is proposed, as a first step towards the specification of light electric-powered vehicles in the European traffic noise predicting method.

Hybridization, that is a adding one or more electric machines powered by a battery to a conventional powertrain, is a promising way to achieve fuel consumption and pollutant emission reduction. Several mechanical arrangements can be considered. A control strategy is required to choose at each sampling time the power split between the engine and the electric machine. In simulation over known driving cycle, this problem can be formulated has an optimal control one. Dynamic programming leads to a shortest path problem over an oriented graph. The minimum principle has also been used and leads to a faster but suboptimal algorithm

The FOREVER (Future OpeRational impacts of Electric Vehicles on national European Roads) project was commissioned, as part of the CEDR Transnational Road Research Programme Call 2012 on Noise, to provide information to NRAs with respect to this issue. The project was developed with three key objectives: - To identify the noise emission levels from electric and hybrid vehicles. This has been achieved through practical measurements of noise from electric and hybrid cars, vans and trucks. The information has been used to develop correction factors to allow such vehicles to be included within state-of-the-art noise prediction models and to investigate subjective responses to these vehicles when part of traffic on NRA roads. - To identify the noise emission of tyres used on electric and hybrid vehicles. This has been achieved through practical measurements of noise for different types of tyres, with the aim of identifying whether specific tyres are/can be used for electric vehicles. - To assess the potential future noise impacts of electric and hybrid vehicles. A state-of-the-art noise prediction model has been used, with data from the practical trials, to assess the noise impacts close to the road for a range of different road type/traffic speed/traffic composition scenarios.

Internoise 2012, NEW YORK, ETATS-UNIS, 19-/08/2012 - 22/08/2012; In relation with traffic restrictions and congestion within cities during daytime hours, the 'last kilometer' for goods delivery turns out to be problematic. Hybrid trucks may be a worthwhile solution, especially for activities at very early or late hours. Apart from some noise reduction figures put forward by manufacturers or concerned users, the actual noise benefit of these vehicles is not well known. The present study assesses the noise emission of one hybrid distribution truck, either in hybrid or electric mode, over wide real usage conditions, and compares it to an equivalent full thermic truck. Constant speed pass-bys as well as accelerating or braking phases are tested. Measurement includes third-octave and global standard 7.5 m noise levels, noise source analysis resulting from microphone array processing, and vertical directivity. The truck in hybrid mode comes out to be a little less noisy than the full thermic one at constant speeds, but deteriorates when accelerating, mainly due to drive tire characteristics. The electric mode benefit exceeds 8 dB(A) at low speed, reduces at higher speeds and vanishes beyond 50 km/h. Due to dramatic motor noise reduction, the drive wheel rolling noise becomes then the main noise contributor over the whole usage range. Moreover the electric mode results in lower directivity in upward directions (building storeys).

Print ISBN: 978-1-4673-2247-8 INSPEC Accession Number: 13225540; International audience; Fuel cell vehicles (FCV) are characterized by the utilization on the same electric bus of an hydrogen fuel cell (FC) stack as a primary energy source and a storage element like batteries as energy storage system. In our project, the fuel cell is a Polymer Electrolyte Membrane (PEM), which is well adapted for transport field applications. A lithium rechargeable battery, more specifically a LiFePO4, is used to supplement the FC over the driving cycle. According to the requirements of the drive cycle of the vehicle, a 20 kW PEM FC system and a 5 kWh LiFePO4 battery are considered here. To define the power supplied by the source and the energy storage system, an energy management system (EMS) is used. A power split strategy is implemented in the EMS in order to obtain an optimal behaviour for the vehicle in terms of hydrogen consumption and considering the constraints of the system (FC and battery dynamics). Due to the non linear FC dynamics, a non linear control is applied which results in a simplification of the optimization problem.