Les réseaux de capteurs sans fils (WSN) ont connu un succès important ces dernières années, en particulier grâce à l’émergence de l’Internet des Objets (IoT), qui a permis des applications beaucoup plus intéressantes. Les réseaux de capteurs sont utilisés dans presque toutes les applications de maisons et villes intelligentes et des objets connectés personnels. Beaucoup de ces applications nécessitent que les nœuds de capteurs constituant le réseau soient autonomes et donc efficaces en énergie. Le thème de l'efficacité énergétique pour les WSN est riche et adressé par de nombreuses équipes de recherches. L'une des solutions les plus prometteuses est l'intégration de blocs adaptatifs dans le nœud, qui peuvent ajuster leurs performances et leurs dépenses énergétiques selon les besoins de l'application, son environnement ou l’énergie disponible. L’objectif est de permettre à un nœud de fonctionner à un point d'énergie optimal et d'atteindre l'efficacité énergétique la plus élevée possible. Le travail présenté dans cette thèse traite du contrôle de ces blocs adaptatifs. Un nœud de WSN doit être capable de se réveiller et de se remettre en veille rapidement ce qui impose l'utilisation d'un réseau de contrôle efficace. Les données de contrôle peuvent être analogiques ou numériques. Ceci entraîne le besoin d'un réseau de communication complémentaire au réseau qui sert à transmettre les données numériques. Dans ce travail, un premier réseau de communication asynchrone est proposé pour adresser ce besoin de transfert de données de configuration dans un nœud. Cette communication basée sur événement utilise la logique asynchrone QDI. Ce premier réseau est numérique et deux versions ont été conçues, une série et une hybride. La version série a été implémentée en silicium et testée. Les deux se sont avérées efficaces en énergie ; le réseau série n’utilise que 1pJ/bit, tandis que l'hybride consomme 0,07pJ/bit à 0.6V en technologie FDSOI de 28nm.Dans la deuxième partie de ce travail, une amélioration visant des circuits plus simples et mixtes a été réalisée, incluant la conception et l'analyse d'un réseau capable de transférer efficacement des données analogiques. / Wireless sensor network (WSN) have experienced an incredible success these past years, especially due to the Internet of Thing (IoT) paradigm, which opened the door to much more interesting applications. The wireless sensor network nodes (WSNN) are used in nearly all smart houses applications, as a network of wearables or as entertainment devices. This keen interest in WSN is not without consequences, as many of these applications require from the node to be autonomous and thus energy efficient. The topic of energy efficiency for the WSN is rich and many teams are proposing as many solutions as there are applications. One of the most promising solutions is the integration of adaptive blocks in the node, which can adapt their performances and thus their energy expenditure according to the application, environment or the energy budget. This would allow any type of WSNN to operate at an optimum energy point and achieve the highest energy efficiency possible. However, this solution has its own issues. The work presented in this thesis deals with the control of these adaptive blocks.The aim of this work is to efficiently transfer the control data and the sense&react data throughout the node to and from the corresponding adaptive blocks. The nature of WSNN itself imposes the use of a communication network capable of a fast and independent wake and sleep mode, while the nature of the data dictate the need for a complementary communication network, as the data can be either analog or digital, and as such, a typical network is not capable of handling it without the help of secondary conversion blocks.In this manuscript, a first asynchronous communication network is proposed to deal with the issue at hand, mainly the transfer of configuration data throughout a network, in an event-driven fashion, hence the use of the QDI asynchronous logic. This network is digital only and two versions were designed, a serial and a hybrid one, and the serial version was implemented in silicon. Both proved to be energy efficient, as the serial network only needs 1pJ/bit, while the hybrid one consumes 0,07pJ/bit at 0.6V in a 28nm FDSOI technology.In the second part of this work, an improvement targeting simpler and mixed-signals circuits was carried out, including the design and analysis of a network capable of efficiently transferring analog data.

AN ABSTRACT OF THE THESIS OF PRASHANTHI BANALA, for the Master of Science degree in ELECTRICAL AND COMPUTER ENGINEERING, presented on 31 October 2011, at Southern Illinois University Carbondale. TITLE: OUTPUT FEEDBACK H-inf CONTROL DESIGN FOR MULTI-AGENT SYSTEMS MAJOR PROFESSOR: Dr. Farzad Pourboghrat In this thesis, the design of distributed control for identical multi-agent systems is considered based on the optimization of H-inf cost function. Identical dynamically coupled but interacting systems (agents) are considered where control action of each agent is based on relative output measurement of their neighboring agents and a subset of their own output. The agents communicate with each other to achieve a common goal. A distributed dynamic output feedback control strategy that satisfies H-inf performance for multi-agent systems is developed and corresponding H-inf performance region is analyzed. An example illustrates the necessary and sufficient condition for dynamic output feedback controller synthesis to obtain desired H-inf performance.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A distributed power supply composed of multiple DC-DC converters connected in parallel offers several advantages in comparison to a centralized solution. Among these benefits are the following: redundancy, system modularity, increased reliability, improved thermal ow on the system and reduction in the physical size of the units. Its main purpose is to evenly share the output current between the converters. In practice, this specification is rarely achieved without the use of a specific control strategy for sharing, since each converter produces output dependent on the tolerances of the components and the line impedance that connects the unit to the load bus. This imbalance in the shared current can cause excessive stress on the units operating outside of their specifications, increasing their chances of failure. Also, it is desirable that any points of failure are minimized or eliminated by adopting a decentralized control strategy, minimizing connections between units. In this work, the generalized model of output current for a i -th converter from a source with n converters connected in parallel is obtained. To obtain this model, each converter present in the system is modeled as a controlled voltage source, connected to the load bus through an individual line resistance. As the main contribution, two strategies to control current sharing between converters are proposed, based on parallelism without communication between modules, specifically the droop control. To validate the design, the simulation results for a power supply containing three converters in parallel applied to a LED street lamp fixture are shown and analyzed. At the end of this document, the conclusions and suggestions for future work involving the subject are developed. / Uma fonte distribuída de potência composta por vários conversores CC-CC conectados em paralelo oferece diversas vantagens em comparação a uma solução centralizada. Entre esses benefícios, destacam-se os seguintes: redund^ancia, modularidade do sistema, aumento da confiabilidade, melhoria no uxo térmico do sistema e redução no tamanho físico das unidades. Seu principal objetivo é compartilhar uniformemente a corrente de saída entre os conversores. Na prática, esta especificação é raramente atingida sem o emprego de uma estratégia de controle específica para o compartilhamento, visto que cada conversor produz saída dependente das tolerâncias de seus componentes e da impedância de linha que o conecta ao barramento de carga. Este desequilíbrio nas correntes compartilhadas pode ocasionar estresse excessivo nas unidades operando fora de suas especificações, aumentando suas chances de falha. Ainda, é desejável que quaisquer pontos de falha sejam minimizados ou eliminados através da adoção de uma estratégia de controle descentralizada, minimizando conexões entre os conversores. Neste trabalho, o modelo generalizado de corrente para um i -ésimo conversor constituinte de uma fonte com n conversores conectados em paralelo é obtido. Para obtenção deste modelo, modelou-se cada conversor presente no sistema como uma fonte de tens~ao controlada, conectado ao barramento de carga através de uma resistência de linha individual. Como principal contribuição, são apresentadas duas estratégias de controle para compartilhamento de corrente entre conversores, baseados no paralelismo sem comunicação entre módulos, mais especificamente o controle por decaimento. Para validar o projeto, são mostrados e analisados os resultados de simulação para uma fonte de potência contendo três conversores em paralelo aplicados a uma lâmpada de LEDs para iluminação pública. No final deste documento, as conclusões e sugestões para futuros trabalhos envolvendo o tema são elaboradas.

Frente a abrangente presença da internet no ambiente acadêmico e residencial, a literatura relata, na última década, um número crescente de experiências de ensino a distância na área de automação e controle industrial, nas quais desde procedimentos teóricos até aulas práticas podem ser realizados através de acesso remoto. Neste contexto, este trabalho apresenta o estado da arte sobre as experiências acadêmicas no emprego de laboratórios on-line relacionados à teoria de controle e introduz uma nova proposta de arquitetura de acesso remoto, que será aplicada ao ensino de sistemas de controle distribuídos via rede de campo no protocolo FOUNDATION Fieldbus em ambiente simulado. / Due to the increasing presence of the internet in the academic and residential environment, the literature shows an increasing number of experiences of distance learning in the automation and industrial control area in the last decade, in which theoretical procedures as well as practical lessons can be carried out through remote access. In this context, this dissertation presents a brief survey on the academic experiences in the application of on-line laboratories and introduces a new proposal of remote access architecture that will be applied on a distance learning experience in the networked control systems area based on the FOUNDATION Fieldbus protocol using a simulated environment.

Sistemas de controle distribuídos cujas malhas são fechadas através de uma rede de comunicação são chamados de sistemas de controle distribuídos em redes de comunicação (NCS - Networked Control System). Este tipo de arquitetura permite a divisão do sistema de controle em módulos interconectados através da rede de comunicação, proporcionando a divisão do processamento, a redução de custo e de peso, além de facilitar o diagnóstico e manutenção do sistema e de aumentar a sua exibilidade e agilidade; e por isso seu emprego na indústria está se tornando comum (e.g., y-by-wire e drive-by-wire). Porém, a distribuição do processamento e a inserção de uma rede de comunicação aumenta a complexidade da análise e do projeto deste tipo de sistema. Um dos fatores que contribui para esse aumento da complexidade é a presença de atrasos aleatórios nos sinais de controle, causados pela dinâmica do sistema computacional (conjunto de hardware e software) que serve como plataforma para implementação do sistema de controle digital. Este trabalho faz um estudo sobre este tipo de sistema sob a perspectiva destes sinais com atrasos. Para isso, faz-se uso dos toolboxes para MATLAB: TrueTime e Jitterbug. Através destas ferramentas, mostra-se a existência de uma relação de compromisso entre o desempenho do controle e o desempenho do sistema computacional. Através deste estudo, é proposto uma solução de um sistema de controle do tipo NCS para um ROV (do inglês Remotely Operated Vehicle), modelado através de 6 equações diferenciais desacopladas não-lineares. Este tipo de veículo tem uma relevância econômica significativa para o Brasil, visto que é utilizado em operações de manutenção e instalação de plataformas de extração do petróleo que está depositado em profundidades que variam de mil a 2 mil metros. Para este NCS proposto, são utilizados controladores do tipo PI com estrutura feedback-feedfoward cujos parâmetros de projeto são obtidos em função dos atrasos inseridos pelo sistema computacional. / Distributed control systems wherein the control loops are closed through a communication network are called Networked Control Systems (NCSs). This type of architecture allows the control systems division into modules interconnected through the communication network, providing the processing division, reduction of cost and weight, and facilitates the systems diagnosis and maintenance, and increases their exibility and agility. Therefore its use in industry is becoming common (eg, y-by-wire and drive-by-wire). However, the processing distribution and the communication network insertion increase the system analysis and design complexity. One of the factors that contributes to this increased complexity is the presence of random time delays, caused by the dynamics of the computer system (set of hardware and software) used as a platform for digital control system implementation. This work deals with the networked control systems under these random time delays view. For this, it is used two MATLAB toolboxes: Jitterbug and TrueTime. With these tools, it is shown the existence of a relationship between the performance of control and performance of computer system. With this study, it proposed a solution of a NCS for a ROV (Vehicle Operated Remotely), modeled by 6 differential nonlinear decoupled equations. This type of vehicle has a significant economic relevance for Brazil, as it is used in maintenance and installation of platforms for oil extraction deposited at depths ranging from thousand to 2 thousand meters. For this proposed NCS are adopted PI controllers with feedfoward-feedback structure whose parameters design are given in terms of delay inserted by the computer system.

Microgrid is an emerging technology in the eld of electrical engineering which employs the concept of Distributed Energy Resources (DERs) in order to generate electricity in a small sized power system. The main objectives of this dissertation are to: 1- design a new control for lower level control of DERs in microgrids, 2- implement distributed upper level control for DERs in microgrids and 3- apply analytical approaches in order to analyze DERs in microgrids. The control in each DER can be divided into two main categories: lower and upper level. Lower level control is the main objective of control in each DER. For example, the lower level control in Photovoltaic (PV) is in charge of transferring the maximum power from sun into the main grid. Unlike the lower level control, the upper level control is an additional control loop on top of the lower level controls. For example, Voltage/Frequency (VF) controllers are installed on top of Active/Reactive (PQ) power controller in energy storage devices as upper level control. In this dissertation, for the lower level control improvements, two widely used DERs are selected (PV, and oshore wind farm) and new control algorithms are developed in order to improve the performance of lower level controllers in these DERs. For the PV lower level improvement, a new control methodology is proposed in order to minimize the maximum power tracking error in PV lower level controller. Second contribution in lower level control is for the oshore wind farm applications based on Multi-Terminal High Voltage Direct Current (MTDC) transmission; a new control is designed in order to minimize the losses in transmission lines through lower level control of High Voltage Direct Current (HVDC) converters. For the upper level control, this dissertation considers the energy storage as another mostly used type of DER in microgrids. The lower level control for energy storage is in charge of controlling the PQ of the energy storage. The main contribution in the upper level control is to implement the distributed control algorithm based on consensus theory for battery energy storages in order to maximize the efficiency, energy management as well as synchronizing the performance of parallel energy storage devices in microgrids. In this case, the consensus based distributed control algorithm with limited information exchange between neighboring energy storage units is proposed and implemented to validate the claim. The third contribution of this research is to apply advanced analysis techniques to evaluate the performance of the DERs in microgrids. Two approaches are introduced for microgrid modeling in this research. Firstly, an impedance modeling technique is used to model the oshore wind farm connected to the main AC grid through HVDC transmission line. Multiple Input Multiple Output (MIMO) Nyquist analysis and singular value analysis are used to assess the interactions between HVDC converter and grid. Secondly, an unbalanced microgrid is considered and Dynamic Phasor (DP) analysis is applied in order to nd the stability limitations under different scenarios. This dissertation has led to seven journal papers (five published, one journal in revision process and one journal submitted recently) and four conference papers.

The rapidly expanding power system grid infrastructure and the need to reduce the occurrence of major blackouts and prevention or hardening of systems against cyber-attacks, have led to increased interest in the improved resilience of the electrical grid. Distributed and decentralized control have been widely applied to computer science research. However, for power system applications, the real-time application of decentralized and distributed control algorithms introduce several challenges. In this dissertation, new algorithms and methods for decentralized control, protection and energy management of Wide Area Monitoring, Protection and Control (WAMPAC) and the Active Distribution Network (ADN) are developed to improve the resiliency of the power system. To evaluate the findings of this dissertation, a laboratory-scale integrated Wide WAMPAC and ADN control platform was designed and implemented. The developed platform consists of phasor measurement units (PMU), intelligent electronic devices (IED) and programmable logic controllers (PLC). On top of the designed hardware control platform, a multi-agent cyber-physical interoperability viii framework was developed for real-time verification of the developed decentralized and distributed algorithms using local wireless and Internet-based cloud communication. A novel real-time multiagent system interoperability testbed was developed to enable utility independent private microgrids standardized interoperability framework and define behavioral models for expandability and plug-and-play operation. The state-of-theart power system multiagent framework is improved by providing specific attributes and a deliberative behavior modeling capability. The proposed multi-agent framework is validated in a laboratory based testbed involving developed intelligent electronic device prototypes and actual microgrid setups. Experimental results are demonstrated for both decentralized and distributed control approaches. A new adaptive real-time protection and remedial action scheme (RAS) method using agent-based distributed communication was developed for autonomous hybrid AC/DC microgrids to increase resiliency and continuous operability after fault conditions. Unlike the conventional consecutive time delay-based overcurrent protection schemes, the developed technique defines a selectivity mechanism considering the RAS of the microgrid after fault instant based on feeder characteristics and the location of the IEDs. The experimental results showed a significant improvement in terms of resiliency of microgrids through protection using agent-based distributed communication.

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This thesis describes creation of dynamically evolvable node, which will cooperate with other nodes. Group of these nodes will then create a distributed control system. The MQTT protocol is used for communications purposes between individual nodes. As hardware platform is used ESP32 and ESP8266. Whole operating system is written in MicroPython and supports a live uploading of user applications written in the same language. Later in thesis is decribed creation of monitoring node on Raspberry Pi, which control network. Complete system can be then used to control a intelligent house.

En ce qui concerne la hiérarchie de contrôle des micro-réseaux, la coordination des contrôleurs locaux est obligatoire aux niveaux secondaire et tertiaire. Au lieu d'utiliser une unité centrale comme approche conventionnelle, dans ce travail, des schémas distribués sont considérés. Les approches distribuées ont récemment fait l'objet d'une attention particulière en raison de leurs avantages en termes de fiabilité, d'évolutivité et de sécurité. Le système multi-agents est une technique avancée dont les propriétés les rendent aptes à servir de base à la construction de systèmes de contrôle distribués modernes. La thèse porte sur la conception d'agents visant à distribuer des algorithmes de contrôle et d'optimisation dans des micro-réseaux avec un déploiement en ligne réaliste sur une plate-forme Hardware-in-the-Loop. Sur la base de l'architecture à trois couches fournie par micro-réseaux, une plate-forme de laboratoire avec configuration Hardware-in-the-Loop est construite au niveau du système. Cette plateforme comprend deux parties : (1) un simulateur numérique en temps réel permet de simuler en temps réel des micro-réseaux de cas de test avec des contrôleurs locaux ; et (2) un cluster de Raspberry PI représente le système multi-agent fonctionnant dans un réseau de communication physique épars. Un agent est un programme en Python exécuté sur un seul Raspberry PI qui permet de transférer des données à ses voisins et d’effectuer des calculs selon des algorithmes de manière distribuée.Dans la thèse, nous appliquons les algorithmes distribués pour les niveaux de contrôle secondaire et tertiaire. Les contrôles secondaires distribués dans un micro-réseau îloté sont présentés selon deux approches d'algorithme de consensus à temps fini et d'algorithme de consensus moyen avec les améliorations des performances. Une extension de la plate-forme avec la Power Hardware-in-the-Loop et la communication basée sur la norme IEC 61850 est traitée pour rapprocher le déploiement des agents des applications industrielles. Au niveau de contrôle supérieur, les agents exécutent la méthode des multiplicateurs à sens alternatif pour déterminer les points de fonctionnement optimaux des systèmes de micro-réseaux en état d'îlot et de connexion au réseau. Les objectifs de contrôle secondaire et tertiaire sont atteints dans un cadre unique qui est rarement mentionné dans d'autres études.Dans l'ensemble, l'agent est explicitement étudié et déployé dans des conditions réalistes pour faciliter l'application des algorithmes distribués pour le contrôle hiérarchique dans les micro-réseaux. Cette recherche constitue une étape supplémentaire qui rapproche les algorithmes distribués de l'implémentation sur site. / In terms of the control hierarchy of microgrids, the coordination of local controllers is mandatory in the secondary and tertiary levels. Instead of using a central unit as conventional approaches, in this work, distributed schemes are considered. The distributed approaches have been taken attention widely recently due to the advantages of reliability, scalability, and security. The multi-agent system is an advanced technique having properties that make them suitable for acting as a basis for building modern distributed control systems. The thesis focuses on the design of agents aiming to distributed control and optimization algorithms in microgrids with realistic on-line deployment on a Hardware-in-the-loop platform. Based on the provided three-layer architecture of microgrids, a laboratory platform with Hardware-in-the-loop setup is constructed in the system level. This platform includes two parts: (1) a digital real-time simulator uses to simulate test case microgrids with local controllers in real-time; and (2) a cluster of hardware Raspberry PIs represents the multi-agent system operating in a sparse physical communication network. An agent is a Python-based program run on a single Raspberry PI owing abilities to transfer data with neighbors and computing algorithms to control the microgrid in a distributed manner.In the thesis, we apply the distributed algorithms for both secondary and tertiary control level. The distributed secondary controls in an islanded microgrid are presented in two approaches of finite-time consensus algorithm and average consensus algorithm with the improvements in performances. An extension of the platform with Power Hardware-in-the-Loop and IEC 61850-based communication is processed to make the deployment of agents closer to industrial applications. On the top control level, the agents execute the Alternating Direction Method of Multipliers to find out the optimal operation points of microgrid systems in both islanded and grid-connect state. The secondary and tertiary control objectives are achieved in a single framework which is rarely reported in other studies.Overall, the agent is explicitly investigated and deployed in the realistic conditions to facilitate applications of the distributed algorithms for the hierarchical control in microgrids. This research gives a further step making the distributed algorithms closer to onsite implementation.