In recent years the number of bicycles with e-motors has been increased steadily. Within the pedelec – bikes where an e-motor supports the pedaling – a special group of transportation bikes has developed. These bikes have storage boxes in addition to the basic parts of a bike. Due to the space available on top of those boxes it is possible to install a PV system to generate electricity which could be used to recharge the battery of the pedelec. Such a system would lead to grid independent charging of the battery and to the possibility of an increased range of motor support. The feasibility of such a PV system is investigated for a three wheeled pedelec delivered by the company BABBOE NORDIC.The measured data of the electricity generation of this mobile system is compared to the possible electricity generation of a stationary system.To measure the consumption of the pedelec different tracks are covered, and the energy which is necessary to recharge the bike battery is measured using an energy logger. This recharge energy is used as an indirect measure of the electricity consumption. A PV prototype system is installed on the bike. It is a simple PV stand alone system consisting of PV panel, charge controller with MPP tracker and a solar battery. This system has the task to generate as much electricity as possible. The produced PV current and voltage aremeasured and documented using a data logger. Afterwards the average PV power is calculated. To compare the produced electricity of the on-bike system to that of a stationary system, the irradiance on the latter is measured simultaneously. Due to partial shadings on the on-bike PV panel, which are caused by the driver and some other bike parts, the average power output during riding the bike is very low. It is too low to support the motor directly. In case of a similar installation as the PV prototype system and the intention always to park the bike on a sunny spot an on-bike system could generate electricity to at least partly recharge a bike battery during one day. The stationary PV system using the same PV panel could have produced between 1.25 and 8.1 times as much as the on-bike PV system. Even though the investigation is done for a very specific case it can be concluded that anon-bike PV system, using similar components as in the investigation, is not feasible to recharge the battery of a pedelec in an appropriate manner. The biggest barrier is that partial shadings on the PV panel, which can be hardly avoided during operation and parking, result in a significant reduction of generated electricity. Also the installation of the on-bike PV system would lead to increased weight of the whole bike and the need for space which is reducing the storage capacity. To use solar energy for recharging a bike battery an indirect way is giving better results. In this case a stationary PV stand alone system is used which is located in a sunny spot without shadings and adjusted to use the maximum available solar energy. The battery of the bike is charged using the corresponding charger and an inverter which provides AC power using the captured solar energy.

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In modern healthcare organizations, work is increasingly team-oriented, which puts pressure on information technology to support staff collaborations. Healthcare organizations are lagging behind in the use of IT and often use outdated systems. A reason for this is the long and cumbersome process of IT-procurement. Stand-alone systems can help such organizations be more efficient, and receptive of the latest technologies, while conveying lower risks, and increased chances of successful implementation. Therefore, this study has investigated what problems can be expected, and how to manage them, when designing such systems. The study was conducted at the Department for Reconstructive Surgery at Karolinska University Hospital. Action research was used, and a system supporting the scheduling of doctors was deigned, implemented and evaluated. The study consists of an initial exploratory phase, a design and implementation phase, and an evaluation phase. The findings of this study indicate that the problems that can be expected when developing a stand-alone system at a small specialized healthcare department are: 1) that the hierarchies among staff may lead to failure to accept designs and the designs not taking all stakeholders into account, 2) that the complexity may lead to an inability to identify the real problems and define appropriate design-goals, and 3) that the combination of 1 and 2 hinders a mutual understanding of design-goals, problems, and solutions. To manage the problems, this study suggests the use of participatory design, user centered system design, and a computer supported collaborative work approach, and provides guidelines for using these to reach an effective implementation. / I moderna sjukhus arbetar man allt mer team-orienterat, vilket ställer krav på system och programvara att stödja samarbeten personalen emellan. Inom sjukvården sker anskaffandet av nya tekniker genom om offentlig upphandling, vilka är tungrodda processer som tar lång tid. Detta leder till att många sjukhus har utdaterade system som inte tjänar organisationernas bästa. Genom att anskaffa mindre, fristående system kan mottagligheten för de senaste teknikerna ökas, och med denna kan även en ökad effektivitet av administrativt arbete uppnås, till låg risk och med möjlighet till effektiv implementation. Av dessa anledningar har denna studie undersökt vilka problem som kan förväntas vid utveckling av sådana system, och hur dessa problem kan överbryggas. Studien utfördes på Kliniken för Rekonstruktiv Plastikkirurgi på Karolinska Sjukhuset i Solna. Vi använde oss av aktionsforskning, och utvecklade, implementerade samt utvärderade ett stödsystem för schemaläggningsprocessen på kliniken. Studien består av tre faser: en explorativ fas, en design- och implementationsfas, samt en utvärderingsfas. Resultaten visar på att de problem som kan förväntas när man utvecklar ett fristående system för en specialiserad kirurgklinik är: 1) att hierarkier inom personalstyrkan kan leda till att utformningen av system inte accepteras, och att system inte bistår alla intressenter, 2) att organisationens komplexitet gör det svårt att identifiera de underliggande problemen, och definiera ändamålsenliga målsättningar för utformningen av systemet, och 3) att kombinationen av 1 och 2 hindrar en ömsesidig förståelse för utformningen av systemet, de problem som finns, och hur man kan lösa dem. Vidare visar denna studie att problemen kan överbryggas genom att använda metoder för deltagande design, användarcentrerad design och en modell för synsätt kallad computer supported collaborative work under designprocessen. Vidare tillhandahåller studien riktlinjer för hur dessa metoder och synsätt kan användas för att uppnå en effektiv implementation.

Ce mémoire présente le travail de recherche effectué pour la conception d'une stratégie de commande originale, destinée aux systèmes de puissance hybrides en sites isolés. Le système considéré, voué à l'alimentation électrique d'une habitation, comprend deux sources, un groupe de panneaux photovoltaïques et une petite éolienne, et deux types de stockage, un banc de batteries lithium-ion et un de supercondensateurs. Face au problème de gestion de l'énergie dans un système hybride, et aux enjeux de maximisation de sa puissance produite, nous proposons de développer une stratégie de commande basée sur les flux d'énergie. pour cela, nous présentons dans un premier temps les modélisations d'Euler-Lagrange et hamiltonienne du système. Ces modèles permettent d'utiliser la propriété de passivité de celui-ci, et ainsi de synthétiser des commandes par injection d'amortissement pour chaque source, afin de maximiser sa production, et pour les supercondensateurs, dans le but d'assurer une répartition cohérente des flux d'énergie entre eux et les batteries. Les commandes sont finalement mises en œuvre dans un simulateur, puis dans un banc d'essai expérimental, afin d'une part de comparer leurs performances à celles de solutions préexistantes, et d'autre part de valider le bon fonctionnement du système hybride complet les utilisant. / This thesis presents the research about design of a new control strategy for stand-alone hybrid power systems. The considered system is composed of two sources, a group of photovoltaic panels and a low-power wind generator, and of two kinds of storage, a bank of lithium-ion batteries and one of supercapacitors. Faced with the problem of energy management in a hybrid power system, and with necessity of maximizing the produced power, we intend to develop an energy-based control strategy.For this purpose, we present the system's Euler-Lagrange modeling and Hamiltonian modeling. These models allow the use of the passivity property, and then the design of Passivity-Based Controllers for each source, in order to maximize its production, and for the supercapacitors, to ensure a fitted power sharing between batteries and them. The controllers are finally implemented in a simulator, and then in a experimental test bench, in order to compare their performances to pre-existent solutions, and tovalidate the control law for the global hybrid system.

Electrification of isolated rural areas in developing countries is a key action for the total eradication of energy poverty. A growing number of authors argue that this electrification should be done with distributed energy systems that combine different renewable energy sources, rather than trying to reach these communities with grid extensions. This is evidenced by numerous projects that have been carried out over the last years in different developing countries with different needs, climatic conditions and resources. These projects have very scarce resources and therefore need to be optimised. To do so, it would be very important to standardise their design, but this is very difficult as there are many variables involved. One of the most common design decisions that remains to be standardised is the question: What is the best way to bring the electricity supply to all the houses in the rural area being electrified? This Master Thesis has worked on solving this question by developing a prefeasibility tool which includes a mathematical model of the energy dispatch which minimizes the OPEX, a function which calculates the CAPEX and a final function which obtains the LCOE of the system by using the outputs of the forementioned model and tool. The tool has been implemented into the programming language Julia. Some of the parameters that need to be input to the model are the number of households, geographical distances between households, types of cables, transformers, generation technologies installed powers, among others. Besides, once the tool has been developed a series of tryouts and analysis have been carried out to confirm the robustness of the tool as well as to learn more about the behaviour of the costs structure. By carrying out the analysis of the results, the tool has successfully proven its validity. Moreover, a sensitivity analysis has been carried out to answer questions like which is the cheapest option, keeping a household isolated from the clusters or creating a stand-alone system for it? To sum up, as it has been said, this thesis has tried to answer the question settled previously with the aim of creating a useful and standard tool that could help other similar projects in their decision-making processes. / Elektrifiering av isolerade landsbygdsområden i utvecklingsländer är en nyckelåtgärd för att totalt utrota energifattigdomen. Ett växande antal författare hävdar att denna elektrifiering bör göras med distribuerade energisystem som kombinerar olika förnybara energikällor, snarare än att försöka nå dessa samhällen med nätutbyggnader. Det vittnar om ett flertal projekt som har genomförts under de senaste åren i olika utvecklingsländer med olika behov, klimatförhållanden och resurser. Dessa projekt har mycket knappa resurser och behöver därför optimeras. För att göra det skulle det vara mycket viktigt att standardisera deras design, men detta är mycket svårt eftersom det finns många variabler inblandade. Ett av de vanligaste designbesluten som återstår att standardisera är frågan: Vad är det bästa sättet att få elförsörjningen till alla hus på landsbygden som elektrifieras? Denna masteruppsats har arbetat med att lösa denna fråga genom att utveckla ett prefeasibility-verktyg som inkluderar en matematisk modell av energisändningen som minimerar OPEX, en funktion som beräknar CAPEX och en slutlig funktion som erhåller LCOE för systemet genom att använda utdata från den tidigare nämnda modellen och verktyget. Verktyget har implementerats i programmeringsspråket Julia. Några av parametrarna som behöver matas in i modellen är bland annat antalet hushåll, geografiska avstånd mellan hushållen, typer av kablar, transformatorer, genereringsteknik installerad kraft. När verktyget har utvecklats har dessutom en serie tester och analyser genomförts för att bekräfta verktygets robusthet samt för att lära sig mer om hur kostnadsstrukturen fungerar. Genom att genomföra analysen av resultaten har verktyget framgångsrikt bevisat sin giltighet. Dessutom har en känslighetsanalys genomförts för att svara på frågor som vilket år det billigaste alternativet, hålla ett hushåll isolerat från klustren eller skapa ett fristående system för det? Sammanfattningsvis, som det har sagts, har denna avhandling försökt besvara den tidigare ställda frågan i syfte att skapa ett användbart och standardverktyg som skulle kunna hjälpa andra liknande projekt i deras beslutsprocesser.