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Among the renewable energies, wind energy presents the highest growth in installed capacity and penetration in modern power systems. This is why reliability of wind turbines becomes an important topic in research and industry. To this end, condition monitoring (or health monitoring) systems are needed for wind turbines. The core of any condition monitoring system (CMS) are fault diagnosis algorithms whose task is to provide early warnings upon the occurrence of incipient (small magnitude) faults. Thanks to the use of CMS we can avoid premature breakdowns and reduce significatively maintenance costs.The present thesis deals with fault diagnosis in sensors of a doubly-fed induction generator (DFIG) for wind turbine (WT) applications. In particular we are interested in performing fault detection and isolation (FDI) of incipient faults affecting the measurements of the three-phase signals (currents and voltages) in a controlled DFIG. Although different authors have dealt with FDI for sensors in induction machines and in DFIGs, most of them rely on the machine model withconstant parameters. However, the parameter uncertainties due to changes in the operating conditions will produce degradation in the performance of such FDI systems.In this work we propose a systematic methodology for the design of sensor FDI systems with the following characteristics: i) capable of detecting and isolating incipient additive (bias, drifts) and multiplicative (changes in the sensorgain) faults, ii) robust against changes in the references/disturbances affecting the controlled DFIG as well as modelling/parametric uncertainties, iii) residual generation system based on a multi-observer strategy to enhance the isolation process, iv) decision system based on statistical-change detection algorithms to treat the entire residual and perform fault detection and isolation at once.Three novel sensor FDI approaches are proposed. The first is a signal-based approach, that uses the model of the balanced three-phase signals (currents or voltages) for residual generation purposes. The second is a model-based approachthat accounts for variation in the parameters. Finally, a third approach that combines the benefits of both the signal- and the model-based approaches is proposed. The designed sensor FDI systems have been validated using measured voltages, as well as simulated data from a controlled DFIG and a speed-controlled inductionmotor. In addition, in this work we propose a discrete-time multiple input multiple output (MIMO) regulator for each power converter, namely for the rotor side converter (RSC) and for the grid side converter (GSC). In particular, for RSCcontrol, we propose a modified feedback linearization technique to obtain a linear time invariant (LTI) model dynamics for the compensated DFIG. The novelty of this approach is that the compensation does not depend on highly uncertain parameters such as the rotor resistance. For GSC control, a LTI model dynamicsis derived using the ideas behind feedback linearization. The obtained LTI model dynamics are used to design Linear Quadratic Gaussian (LQG) regulators. A single design is needed for all the possible operating conditions. Doctorat en Sciences de l'ingénieur info:eu-repo/semantics/nonPublished

The subject of this thesis is the study of the concept of international transfers of green technologies within the United Nations Framework Convention on Climate Change (UNFCCC). The study focuses on the analysis of the evolution of the technology transfer (TT) concept: starting from a model of development aid in the New International Economic Order (NIEO) doctrine, the demand for a true technology transfer has undergone a long evolution in climate governance – including the adoption of a unprecedent Technology Mechanism within the UNFCCC – before getting to the theory of National Innovation Systems (NIS), according to which the states become the real drivers of technological transformation. This evolution corresponds to a contemporary view of the transfers phenomenon. The text is therefore split into three chapters. The first chapter is devoted to the study of the history of the concept of TT since its appearance at the time of the NIEO movement until its transposition to the environmental sphere. The second chapter examines the paradigm transformation operated within the Climate Convention: starting from an exogenous approach, with technology landing in the South countries, the subject TT moves to an endogenous movement of structuring and strengthening of NIS. The third chapter presents a practical study of the arrival of green technology in Brazil, based on statistical data. This has provided important information about the concrete reality of technology transfer to a developing country. Finally, the text concludes with the idea that after the movement for a NIEO, based on the right to development, and multilateral environmental agreements, based on the principles of sustainable development and common but differentiated responsibilities, the NIS doctrine, anchored in the innovation law, seems to have taken the lead in guiding discussions on green technologies transfers. Le sujet de cette thèse est l’étude du concept de transferts internationaux de ‘technologies écologiquement rationnelles’ (TER) dans le cadre de la Convention Cadre des Nations Unies sur les changements climatiques (CCNUCC). L’étude se consacre à analyser l’évolution du concept sur le transfert de technologies (TT) : partant du modèle de développement ‘assistancialiste’ de la doctrine du Nouvel Ordre Économique International (NOEI), la demande pour un véritable transfert technologique a connu une longue évolution au sein de la gouvernance climatique – y compris avec l’adoption d’un inédit Mécanisme Technologique au sein de la CCNUCC - avant d’aboutir à la théorie des Systèmes Nationaux d’Innovation (SNI), selon laquelle les États nationaux deviennent les véritables moteurs de la transformation technologique. Cette évolution correspond à une vision contemporaine du phénomène des transferts. Le texte est ainsi réparti en trois chapitres. Le premier chapitre est consacré à l’étude de l’histoire du concept de TT depuis son apparition à l’époque du mouvement du NOEI jusqu’au moment où il a été transposé vers la sphère environnementale. Le deuxième chapitre étudie la transformation de paradigme opéré au sein de la Convention Climat : d’un approche exogène de départ, avec le débarquement de la technologie dans les pays du Sud, le sujet TT passe à un mouvement endogène de structuration et de renforcement des SNI. Le troisième chapitre présente une étude pratique de l’arrivée des nouvelles TER au Brésil, sur base de données statistiques. Cela a fourni des éléments importants sur la réalité concrète du transfert de technologie vers un pays en développement. Finalement le texte conclue avec l’idée qu’après le mouvement en faveur d’un NOEI, fondé sur le droit au développement, et les Accords Environnementaux Multilatéraux, fondés sur les principes du développement durable et des responsabilités communes mais différenciées, la doctrine des SNI, ancrée sur le droit de l’innovation, semble avoir pris le dessus pour guider les discussions sur les transferts des TER. (DROI - Sciences juridiques) -- UCL, 2018

If architecture is to make sustainable development possible, the answer to the energy question in buildings cannot be limited to the application of constructive standards. Those standards need to be contextualised and accompanied by a comprehensive approach of sustainability. In this context, this thesis confronts the energy topic with its own complexity and its relations with the other dimensions of architecture. Specifically, this thesis proposes four sets of original developments: 1/ a critic of today's leading energy standards in buildings (e.g. Passivhaus and net zero-energy buildings), pointing both their ambition and their focus on the notion of performance; 2/ an identification and overruling of doctrinal rules still used in the field; 3/the opening of research and design leads, including the redefinition of comfort in an ecoumenal approach; 4/ the proposition of a design process based on the notion of risk management and the principle of shared responsibility. Through those developments, this thesis offers an approach of energy quality that attributes to it the properties of a "projet", meaning exemplarity (the look for an ideal), design (combination of conception and production) and stakeholders logic. This connection with the concept of “projet” demonstrates the ability of the energy topic to question the fundamental of architecture: creating places consistence with specific way of life. Si l'on souhaite faire de l'architecture un vecteur de développement soutenable, la réponse à la question énergétique ne peut se limiter à l'application de standards constructifs. Il est nécessaire de contextualiser ces standards et de les compléter d'une approche cohérente avec l'ampleur de l'objectif de soutenabilité. Dans ce cadre, cette thèse place la question énergétique face à sa propre complexité et à ses relations avec les autres dimensions de l'architecture. En particulier, elle propose quatre ensembles de développements originaux : 1/ une critique des démarches actuelles (Passivhaus et bâtiments net zéro-énergie), dénonçant leur limitation à l'idée performance, tout en justifiant leur ambition ; 2/ une identification et un dépassement de règles doctrinales encore présentes dans le domaine ; 3/ l'ouverture de pistes de recherche et de conception, notamment par la mise en perspective de la notion de confort dans une approche écouménale ; 4/ la proposition d'un processus de conception centré sur l'idée de gestion du risque et le principe de responsabilité partagée. Par ces développements, cette thèse propose une approche de la qualité énergétique qui lui attribue les propriétés d'une démarche de projet, à savoir exemplarité (définition d'un idéal), opérativité (association de la conception et de la réalisation) et pronominalisation (identification d'une logique d'acteurs). Ce lien avec la notion de projet démontre la capacité de la question énergétique à interroger l'objet fondamental de l'architecture : la création de lieux correspondant à une certaine façon d'être au monde. (FSA 3) -- UCL, 2013

info:eu-repo/semantics/published

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Le champ de la gestion durable des ressources humaines s'est développé ses deux dernières décennies. Deux types d'approches peuvent être considérées: une perspective durable (sustainable) qui s'inscrit dans la perspective du développement durable et de la CSR en élargissant le champ d'action de la GRH aux dimensions environnementales, sociales et économiques, spécifiquement (green HRM, socially responsabile HRM) ou simultanément (triple bottom line HRM); et une perspective soutenable (livable) qui se fonde sur une autre anthropologie et soutient un management humaniste (common good HRM, humanistic management, management humain). Les deux perspectives sont exposées et analysées à l'aune de leur capacité de renouvellement des approches et de leur impact sociétal.

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Wind generation is one of the most successful sources of renewable energy for the production of electrical energy. Wind power offers relatively high capacities, with generation costs that are becoming competitive with conventional energy sources. However, a major problem to its effective use as a power source is the fact that it is both intermittent and diffuse as wind speed is highly variable and site-specific. This is translated in large voltage and frequency excursions and dynamically unstable situations when fast wind power changes. Very high wind speeds will result in sudden loss of wind generator production. The requirement to ensure that sufficient spinning reserve capacity exists within the system to compensate for sudden loss of generation becomes crucial. From the utilities operators’point of view, the primary objective is the security of the system, followed by the quality of the supplied power.In order to guard the system security and quality of supply and retain acceptable levels, a maximum allowed wind power penetration (wind margin) is normally assumed by the operators. Very conservative methods are used to assess the impact of wind power and the consequences turn to under-exploitation of the wind power potential in a given region. This thesis presents the study of actual methods of wind power assessment, divided into three parts:1. Part I: Impact on the Security of Power Systems2. Part II: Impact on the Power Quality3. Part III: Impact on the Dynamic Security of Power Systems info:eu-repo/semantics/nonPublished Doctorat en sciences appliquées

This text examines how private law tools can (and should) be use to support the transition to a (more)sustainable society