Valeo a développé la première génération de système « Stop and Start » aujourd'hui en production avec Citroën. Ce système d'alterno démarreur entraîné par courroie permet d'arrêter le moteur thermique pendant les phases d'arrêt et de le redémarrer rapidement et silencieusement. Il en résulte un absence totale de nuisances et de consommation durant les phases d'arrêt. Grâce au rendement amélioré de la machine en mode générateur cette technologie permet aussi des économies d'énergie pendant les phases de roulage._x000D_ Le but de ce projet est de développer une technologie innovante d'intégration d'électronique de puissance (IML) afin de mettre sur le marché la deuxième génération du système « Stop and Start » répondant simultanément à une demande de fort volume et de bas coût._x000D_ Le développement de cette technologie est particulièrement innovant et ambitieux, il nécessite le développement :_x000D_ • D'un module de puissance « bras de pont » acceptant des courants continus de 200A allant temporairement jusqu'à 680A piloté par un ASIC de pilotage intégrant le redressement synchrone._x000D_ • D'un module de contrôle en technologie hybride intégrant un ASIC comprenant un cœur de microprocesseur et un circuit d'excitation._x000D_ Cette technologie devra en outre pouvoir :_x000D_ • Assurer une parfaite Compatibilité Electro-Magnétique._x000D_ • Fonctionner dans un environnement très sévère (forte température et niveau vibratoire élevé)._x000D_ • S'intégrer dans le volume d'un alternateur classique._x000D_ • Avoir un niveau de fiabilité équivalent aux alternateurs actuels (moins d'un ppm de défaillance)

L'objectif est de démontrer la pertinence technique, économique et environnementale d'un concept Stop & Start dans le domaine de transport public en zone urbaine. Dans un premier temps étudier pour un véhicule de faible capacité (microbus GRUAU 22 places), l'extension vers des véhicules urbains de plus grande capacité et dotés de motorisations dans la gamme de trois à six litres est également envisageable._x000D_ Le projet comprend, l'étude, la réalisation, l' expérimentation en conditions réelles et la modélisation de la chaîne de traction intégrée. Le système micro-hybride (stop/start) sera ici doté de la récupération d'énergie de freinage par super-condensateurs et convertisseur de tension (StARS+X de Valeo)._x000D_ MICRO2 contribuera à l'accroissement des connaissances des partenaires sur les points suivants : _x000D_ • Dimensionnement et adaptation d'un système « automobile » à la spécification bus :_x000D_ o Fort couple de démarrage_x000D_ o Réseau 24V_x000D_ • Interfaçage du système micro-hybride avec les systèmes de management moteur et véhicule_x000D_ • Meilleure connaissance des conditions de fonctionnement des composants de cette architecture suivant les usages, en particulier pour le système de stockage d'énergie vis-à-vis de son vieillissement en mode stop-start (Supercondensateurs), _x000D_ • Bilan énergie-pollution permettant de faire apparaître le gain potentiel des fonctionnalités stop-start et récupération au freinage suivant un usage de transport collectif, _x000D_ • Développement et validation d'un outil permettant de prédire le gain en consommation d'énergie d'un véhicule issu du concept MICRO2 suivant les conditions de fonctionnement propres à un exploitant,_x000D_

The TELL project addresses the large-scale manufacturing of Low and Mid voltage power converters and more in general Low and Mid voltage powertrain solutions targeting: • The electrification of the small and lower-medium segments accounting for about 70% (8 millions/year) of the current total passenger cars sold in Europe, • Hybrid vehicles adopting a low voltage add-on electric propulsion, • The light weight urban mobility sector which on a global scale is exponentially growing. For the purpose TELL brings together an integrated supply chain including a world leader in Power Semiconductors, 2 leading Tier1s in Automotive and Industrial powertrains, a high-tech Small-Medium enterprise in e-mobility applications and a leading-edge RTO. Specific objectives are: • Develop technologies, know-how and best practices for handling thinner wafers throughout the entire supply chain aiming at increasing the global efficiency in urban mobility and those driving cycles having a high number of stops and starts, • Increase the yield both in the production of chips and at the inverter-level integration, • Explore the potentiality of Wide Bandgap Semiconductors at low voltage using a novel GaN inverter and a novel synchro motor with integrated GaN switches; • Develop two types of advanced super-compact powertrains based on Si-Mosfets and GaN FETS on thin chips with embedded state of-the-art control algorithms enabled by electrical powertrains, • Introduce a higher degree of smartness at a system level in both powertrains. The achievements will be demonstrated in two EV platforms: 4WD operated at a nominal voltage of 100V and 2WD operated at a nominal voltage of 48V. The proposed solutions will be 100% made in Europe, robust, efficient, low-cost: • 25% of cost reduction in mass production with increased user-friendliness and experience, • highest quality devices and two powertrains solutions meeting and overcoming the current automotive standards.

To date, scientific results from studies on the ageing of on-board Energy Storage Systems (ESS), and particularly supercapacitors, are few. The main reasons come from either the confidentiality of the results from the manufacturers, the limited number of technologies actually available and accessible to specialized laboratories, or because the studies do not consider the implementation of ageing laws in the developed models and therefore they are incomplete. However, in case of modern hybrid vehicle applications, the integration of ESS based on supercapacitors requires a realistic estimation of the lifetime of the cells for different profiles of solicitation. This is essential for the optimal design of the ESS because the vehicle has to meet its initial specifications for a lifetime between 10 and 15 years. Moreover, for obvious reasons of cost, which is a criterion for the successful marketing of hybrid vehicles, we can not rely on the initial oversizing of supercapacitor cells. In these conditions, it is essential to have accurate models in order to estimate the lifetime of supercapacitors for different modes of ageing, both in power cycling and calendar modes. In this context, the project SIMSTOCK was launched in 2006 and concerns only the behaviour and the ageing in power cycling and does not take into account the calendar ageing. However, the average utilization rate of a particular vehicle is about 7000 hours for a 15 years lifetime. The calendar ageing appears as a dominant phenomenon and requires a specific research project on this topic as SUPERCAL. The organization of the project SUPERCAL is similar to the SIMSTOCK one takes benefits of both the experience and specific equipment of laboratories and industrial partners. The main objective of SUPERCAL is to develop advanced models for the latest technology of supercapacitors in which the different ageing modes are taken into account. An essential part of this project focuses on endurance tests where the voltage across the supercapacitor is kept constant by an external device whose role is to compensate the self-discharge of the cell. Under these conditions, the ageing is the result of a combined action of both the temperature and the voltage representative of the energetic state of the supercapacitor. The monitoring of the characteristics evolution of the elements is achieved through continuous measurement of leakage current and thanks to periodic characterization tests based on capacitance, equivalent series resistance and impedance measurements. Thus, the calendar lifetime can be quantified thanks to evolution laws of these electrical parameters for fixed voltage and temperature conditions. More specific tests will be conducted with the aim to highlight and study other modes of calendar ageing, which correspond to real solicitations in hybrid vehicles applications. Firstly, from thermal point of view, tests will be conducted to study the impact of a slowly varying temperature profile on the calendar ageing, at a daily or weekly timescale. Then, another objective is to study the influence of the superposition of an alternative voltage component to the constant bias voltage on the changing characteristics of the samples. The link with the project SIMSTOCK and the inter-comparison of the results will be addressed through specific tests based on calendar ageing tests with intermittent cycling periods. Finally, all these results will be analyzed in order to define behavioural laws for the different ageing modes and to implement them into simulation models.