Elke periode kent zijn eigen revolutie en elke revolutie brengt zijn eigen organisatorische model met zich mee. We bevinden ons nu in de 4e industri¨ele revolutie, waar het internet van dingen ons verbindt met autonome embedded systemen. Deze systemen zijn actief in de virtuele ’cyber’ wereld, alsook in de echte ’fysieke’ wereld om ons heen. Deze zogenoemde ’Cyber-Fysieke’ Systemen volgen daarmee een modern organisatorisch model, namelijk zelfmanagement, en zijn dan ook in staat zelf proactieve acties te ondernemen. Dit proefschrift belicht productiesystemen vanuit het Cyber-Fysieke perspectief. De productiesystemen zijn hier herconfigureerbaar, autonoom en zeer flexibel. Dit kan enkel worden bereikt door het ontwikkelen van nieuwe methodes en het toepassen van nieuwe technologie¨en die flexibiliteit verder bevorderen. Echter, effici¨entie is ook van belang, bijvoorbeeld door productassemblage zo flexibel te maken dat het daardoor kosteneffici¨ent is om de productie van diverse producten met een lage oplage, zogenaamde high-mix, low volume producten, te automatiseren. De mogelijkheid om zo flexibel te kunnen produceren moet bereikt worden door de creatie van nieuwe methoden en middelen, waarbij nieuwe technologie¨en worden gecombineerd; een belangrijk aspect hierbij is dat dit toepasbaar getest moet worden door gebruik van simulatoren en speciaal hiervoor ontwikkelde productiesystemen. Dit onderzoek zal beginnen met het introduceren van het concept achter de bijbehorende productiemethodologie, welke Grid Manufacturing is genoemd. Grid Manufacturing wordt uitgevoerd door autonome entiteiten (agenten) die zowel de productiesystemen zelf, als de producten representeren. Producten leven dan al in de virtuele cyber wereld voordat zij daadwerkelijk zijn gebouwd, en zijn zich bewust uit welke onderdelen zij gemaakt moeten worden. De producten communiceren en overleggen met de autonome herconfigureerbare productiesystemen, de zogenaamde equiplets. Deze equiplets leveren generieke diensten aan een grote diversiteit aan producten, die hierdoor op elk moment geproduceerd kunnen worden. Het onderzoek focust hierbij specifiek op de equiplets en de technische uitdagingen om dynamisch geautomatiseerde productie mogelijk te maken. Om Grid Manufacturing mogelijk te maken is er een set van technologische uitdagingen onderzocht. De achtergrond, onderzoeksaanpak en concepten zijn dan ook de eerste drie inleidende hoofdstukken. Daarna begint het onderzoek met Hoofdstuk 4 Object Awareness. Dit hoofdstuk beschrijft een dynamische manier waarop informatie uit verschillende autonome systemen gecombineerd wordt om objecten te herkennen, lokaliseren en daarmee te kunnen manipuleren. Hoofdstuk 5 Herconfiguratie beschrijft hoe producten communiceren met de equiplets en welke achterliggende systemen ervoor zorgen dat, ondanks | Dutch Summary 232 dat het product niet bekend is met de hardware van de equiplet, deze toch in staat is acties uit te voeren. Tevens beschrijft het hoofdstuk hoe de equiplets omgaan met verschillende hardwareconfiguraties en ondanks de aanpassingen zichzelf toch kunnen besturen. De equiplet kan dan ook aangepast worden zonder dat deze opnieuw geprogrammeerd hoeft te worden. In Hoofdstuk 6 Architectuur wordt vervolgens dieper ingegaan op de bovenliggende architectuur van de equiplets. Hier worden prestaties gecombineerd met flexibiliteit, waarvoor een hybride architectuur is ontwikkeld die het grid van equiplets controleert door het gebruik van twee platformen: Multi-Agent System (MAS) en Robot Operating System (ROS). Nadat de architectuur is vastgesteld, wordt er in Hoofdstuk 7 onderzocht hoe deze veilig ingezet kan worden. Hierbij wordt een controlesysteem ingevoerd dat het systeemgedrag bepaalt, waarmee het gedrag van de equiplets transparant wordt gemaakt. Tevens zal een simulatie met input van de sensoren uit de fysieke wereld ’live’ controleren of alle bewegingen veilig uitgevoerd kunnen worden. Nadat de basisfunctionaliteit van het Grid nu compleet is, wordt in Hoofdstuk 8 Validatie en Utilisatie gekeken naar hoe Grid Manufacturing gebruikt kan worden en welke nieuwe mogelijkheden deze kan opleveren. Zo wordt er besproken hoe zowel een hi¨erarchische als een heterarchische aanpak, waar alle systemen gelijk zijn, gebruikt kan worden. Daarnaast laat het hoofdstuk o.a. aan de hand van enkele voorbeelden en simulaties zien welke effecten herconfiguratie kan hebben, en welke voordelen deze aanpak zoal kan bieden.. Het proefschrift laat zien hoe met technische middelen geautomatiseerde flexibiliteit mogelijk wordt gemaakt. Hoewel het gehele concept nog volwassen zal moeten worden, worden er enkele aspecten getoond die op de korte termijn toepasbaar zijn in de industrie. Enkele voorbeelden hiervan zijn: (1) het combineren van gegevens uit diverse (autonome) bronnen voor 6D-lokalisatie; (2) een data-gedreven systeem, de zogeheten hardware-abstractielaag, die herconfigureerbare systemen controleert en de mogelijkheid biedt om deze productiesystemen aan te passen zonder deze te hoeven herprogrammeren; en (3) het gebruik van Cyber-Fysieke systemen om de veiligheid te verhogen.
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Standard mass-production is a well-known manufacturing concept. To make small quantities or even single items of a product according to user specifications at an affordable price, alternative agile production paradigms should be investigated and developed. The system presented in this paper is based on a grid of cheap reconfigurable production units, called equiplets. A grid of these equiplets is capable to produce a variety of different products in parallel at an affordable price. The underlying agent-based software for this system is responsible for the agile manufacturing. An important aspect of this type of manufacturing is the transport of the products along the available equiplets. This transport of the products from equiplet to equiplet is quite different from standard production. Every product can have its own unique path along the equiplets. In this paper several topologies are discussed and investigated. Also, the planning and scheduling in relation to the transport constraints is subject of this study. Some possibilities of realization are discussed and simulations are used to generate results with the focus on efficiency and usability for different topologies and layouts of the grid and its internal transport system.
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Standard mass-production is a well-known manufacturing concept. To make small quantities or even single items of a product according to user specifications at an affordable price, alternative agile production paradigms should be investigated and developed. The system presented in this article is based on a grid of cheap reconfigurable production units, called equiplets. A grid of these equiplets is capable to produce a variety of different products in parallel at an affordable price. The underlying agent-based software for this system is responsible for the agile manufacturing. An important aspect of this type of manufacturing is the transport of the products along the available equiplets. This transport of the products from equiplet to equiplet is quite different from standard production. Every product can have its own unique path along the equiplets. In this article several topologies are discussed and investigated. Also, the planning and scheduling in relation to the transport constraints is subject of this study. Some possibilities of realization are discussed and simulations are used to generate results with the focus on efficiency and usability for different topologies and layouts of the grid and its internal transport system. Closely related with this problem is the scheduling of the production in the grid. A discussion about the maximum achievable load on the production grid and its relation with the transport system is also included.
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Like the professionals, design students tend to avoid the complexity of the user context, and moral issues are largely overlooked. This inspired us to explore whether we could engage design students in thinking about moral issues by exploring different ethical frameworks in their designing. As a case environment we chose smart-grid product service combinations. In this paper we first discuss the ethical frameworks of four selected philosophers’: Plato, Rousseau, Kant, & Mill. Then we will describe the student design process, the resulting four smart grid service concepts and the user insights that came from a user evaluation. We discuss how this approach allowed the students to get insights in their own ethical stance and how they allowed users to reflect on possible futures. We also discuss how these ‘probing’ concepts were used within the larger smart grid project.
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Smart charging protocols for electric vehicles can help avoid overload and instability in the electrical distribution network and can increase the proportion of locally generated solar energy used for charging. Our results show that the impact of smart charging depends heavily on the technical charging characteristics of the target vehicle.
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This paper proposes a Hybrid Microgrid (HμG) model including distributed generation (DG) and a hydrogen-based storage system, controlled through a tailored control strategy. The HμG is composed of three DG units, two of them supplied by solar and wind sources, and the latter one based on the exploitation of theProton Exchange Membrane (PEM) technology. Furthermore, the system includes an alkaline electrolyser, which is used as a responsive load to balance the excess of Variable Renewable Energy Sources (VRES) production, and to produce the hydrogen that will be stored into the hydrogen tank and that will be used to supply the fuel cell in case of lack of generation. The main objectives of this work are to present a validated dynamic model for every component of the HμG and to provide a strategy to reduce as much as possible the power absorption from the grid by exploiting the VRES production. The alkaline electrolyser and PEM fuel cell models are validated through real measurements. The State of Charge (SoC) of the hydrogen tank is adjusted through an adaptive scheme. Furthermore, the designed supervisor power control allows reducing the power exchange and improving the system stability. Finally, a case, considering a summer load profile measured in an electrical substation of Politecnico di Torino, is presented. The results demonstrates the advantages of a hydrogen-based micro-grid, where the hydrogen is used as medium to store the energy produced by photovoltaic and wind systems, with the aim to improve the self-sufficiency of the system
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The Smart Current Limiter is a switching DC to DC converter that provides a digitally pre-set input current control for inrush limiting and power management. Being able to digitally adjust the current level in combination with external feedback can be used for control systems like temperature control in high power DC appliances. Traditionally inrush current limiting is done using a passive resistance whose resistance changes depending on the current level. Bypassing this inrush limiting resister with a Mosfet improves efficiency and controllability, but footprint and losses remain large. A switched current mode controlled inrush limiter can limit inrush currents and even control the amount of current passing to the application. This enables power management and inrush current limitation in a single device. To reduce footprint and costs a balance between losses and cost-price on one side and electromagnetic interference on the other side is sought and an optimum switching frequency is chosen. To reduce cost and copper usage, switching happens on a high frequency of 300kHz. This increases the switching losses but greatly reduces the inductor size and cost compared to switching supplies running on lower frequencies. Additional filter circuits like snubbers are necessary to keep the control signals and therefore the output current stable.
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Author supplied: Abstract—The growing importance and impact of new technologies are changing many industries. This effect is especially noticeable in the manufacturing industry. This paper explores a practical implementation of a hybrid architecture for the newest generation of manufacturing systems. The papers starts with a proposition that envisions reconfigurable systems that work together autonomously to create Manufacturing as a Service (MaaS). It introduces a number of problems in this area and shows the requirements for an architecture that can be the main research platform to solve a number of these problems, including the need for safe and flexible system behaviour and the ability to reconfigure with limited interference to other systems within the manufacturing environment. The paper highlights the infrastructure and architecture itself that can support the requirements to solve the mentioned problems in the future. A concept system named Grid Manufacturing is then introduced that shows both the hardware and software systems to handle the challenges. The paper then moves towards the design of the architecture and introduces all systems involved, including the specific hardware platforms that will be controlled by the software platform called REXOS (Reconfigurable EQuipletS Operating System). The design choices are provided that show why it has become a hybrid platform that uses Java Agent Development Framework (JADE) and Robot Operating System (ROS). Finally, to validate REXOS, the performance is measured and discussed, which shows that REXOS can be used as a practical basis for more specific research for robust autonomous reconfigurable systems and application in industry 4.0. This paper shows practical examples of how to successfully combine several technologies that are meant to lead to a faster adoption and a better business case for autonomous and reconfigurable systems in industry.
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The European Union is striving for a high penetration of renewable energy production in the future energy grid. Currently, the EU energy directive is aiming for 20% renewable energy production in the year 2020. In future plans the EU strives for approximately 80% renewable energy production by the year 2050. However, high penetration of wind and solar PV energy production, both centrally and de-centrally, can possibly destabilize the electricity grid. The gas grid and the flexibility of gas, which can be transformed in both electricity and heat at different levels of scale, can help integrate and balance intermittent renewable production. One possible method of assisting the electricity grid in achieving and maintaining balance is by pre-balancing local decentralized energy grids. Adopting flexible gas based decentralized energy production can help integrate intermittent renewable electricity production, short lived by-products (e.g. heat) and at the same time minimize transport of energy carriers and fuel sources. Hence, decentralized energy grids can possibly improve the overall efficiency and sustainability of the energy distribution system. The flexibility aforementioned, can potentially give gas a pivotal role in future decentralized energy grids as load balancer. However, there are a lot of potentially variables which effect a successful integration of renewable intermittent production and load balancing within decentralized energy systems. The flexibility of gas in general opens up multiple fuel sources e.g., natural gas, biogas, syngas etc. and multiple possibilities of energy transformation pathways e.g. combined heat and power, fuel cells, high efficiency boilers etc. Intermittent renewable production is already increasing exponentially on the decentralized level where load balancing is still lacking.
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The energy community movement has grown considerably over the past ten years. Energy communities are also expanding their activities. However, room for new energy projects is limited because of grid congestion. Therefore, citizen energy communities (CECs) are looking for ways to reduce the pressure on the grid. Against this background we ask what new roles renewable energy communities can play in grid governance. What opportunities are available to store produced electricity or to balance electricity on a neighborhood level? Are these solutions economically and technically feasible? Our article draws on a recent research project on innovative community energy services in the Netherlands. In three case studies, we investigated local solutions to balance energy production and consumption. We organized workshops and webinars for CECs and carried out interviews and technical studies. Theoretically, we use Social Movement Theory (SMT) to understand the community energy movement. Furthermore, we employ Large Technical Systems (LTS) theories about the lifecycle of infrastructures. We investigated the technical, organizational, and economic aspects of these solutions, as well as skills and knowledge. We conclude that the community energy movement is expanding its activities to new functions in the energy system, but economic feasibility is not yet within reach.
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