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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

Dynamometer Characterization of Electric Powertrain Components for Accurate Modeling and Control Design of a Dual-Motor All-Wheel-Drive Electric Vehicle / POWERTRAIN CHARACTERIZATION FOR MODELING AND CONTROL DESIGN

Allca-Pekarovic, Alexander January 2025 (has links)
United States government data shows AWD EV production increasing over 376 % from 2020 to 2023. The literature highlights energy savings from mixed-type dual EM powertrains and optimization-based energy management strategies (EMS), compared to single-type dual-motors and rule-based control. Other trends include the adoption of silicon carbide (SiC) based inverter devices and 800 V systems. Axial-flux machines have seen increased traction, with implementations in Ferrari’s SF90 Stradale, Lamborghini’s Revuelto, and Mercedes-Benz’s acquisition of YASA Ltd. These findings motivated the study of dual-motor AWD EV thermally constrained energy management. Using McMaster Automotive Resource Centre’s (MARC’s) facilities, accurate modeling of powertrain components was pursued to contribute realistic results. Firstly, inverter device materials and voltage ratings were studied in a Chevrolet Bolt EV model. Experimental validation was conducted on 1200 V inverters, powering 160+ kW traction machines. The model’s loss error was mostly within 100 W of measured loss. An empirical loss model revealed the analytical model estimates range within 6 km. This work highlighted the benefits of 800 V DC buses and SiC inverters. Secondly, experimental characterization of a yokeless and segmented armature (YASA) axial flux machine, by YASA Ltd., was documented. Dynamometer tests covered a wide torque, speed, and DC bus voltage range. The Bolt EV was modeled with the YASA machine, comparing its performance to the stock machine. All data was compiled and published in an online open-source repository. Lastly, thermally constrained energy management of various control strategies for a dual-motor AWD EV model were compared. Over two drive cycles, an MPC strategy ranked best in selected performance metrics. During a racetrack drive cycle, the MPC strategy kept the thermally limited motor cooler 246 % longer than a rule-based strategy. This work highlighted MPC’s potential in reducing total lifetime thermal wear of a dual-motor powertrain’s thermally limited motor. / Thesis / Doctor of Philosophy (PhD) / This thesis presents the experimental dynamometer work behind the accurate modeling of electric powertrain components, specifically the electric machine (EM) and inverter. The analytical inverter model is experimentally validated using electric machines as loads. The electric machine model is constructed from its experimental characterization data. Together, these models form a near-completely experimental-based electric drive unit (EDU). From this foundation, a dual-motor all-wheel-drive (AWD) electric vehicle (EV) model is built for the purpose of evaluating various control strategies’ thermally constrained energy management abilities. The control methods are ranked with respect to key performance indicators (KPIs) over the course of two drive cycles. Results from these drive cycles point to the model predictive control (MPC) strategy achieving the control objectives with the best quantified KPIs. Most importantly, it was able to keep the powertrain's thermally limited motor cooler 246 % longer than the second-best performing control strategy, a rule-based method applying a torque-split ratio algorithm.
272

Système de gestion d'énergie d'un véhicule électrique hybride rechargeable à trois roues

Denis, Nicolas January 2014 (has links)
Résumé : Depuis la fin du XXème siècle, l’augmentation du prix du pétrole brut et les problématiques environnementales poussent l’industrie automobile à développer des technologies plus économes en carburant et générant moins d’émissions de gaz à effet de serre. Parmi ces technologies, les véhicules électriques hybrides constituent une solution viable et performante. En alliant un moteur électrique et un moteur à combustion, ces véhicules possèdent un fort potentiel de réduction de la consommation de carburant sans sacrifier son autonomie. La présence de deux moteurs et de deux sources d’énergie requiert un contrôleur, appelé système de gestion d’énergie, responsable de la commande simultanée des deux moteurs. Les performances du véhicule en matière de consommation dépendent en partie de la conception de ce contrôleur. Les véhicules électriques hybrides rechargeables, plus récents que leur équivalent non rechargeable, se distinguent par l’ajout d’un chargeur interne permettant la recharge de la batterie pendant l’arrêt du véhicule et par conséquent la décharge de celle-ci au cours d’un trajet. Cette particularité ajoute un degré de complexité pour ce qui est de la conception du système de gestion d’énergie. Dans cette thèse, nous proposons un modèle complet du véhicule dédié à la conception du contrôleur. Nous étudions ensuite la dépendance de la commande optimale des deux moteurs par rapport au profil de vitesse suivi au cours d’un trajet ainsi qu’à la quantité d’énergie électrique disponible au début d’un trajet. Cela nous amène à proposer une technique d’auto-apprentissage visant l’amélioration de la stratégie de gestion d’énergie en exploitant un certain nombre de données enregistrées sur les trajets antérieurs. La technique proposée permet l’adaptation de la stratégie de contrôle vis-à-vis du trajet en cours en se basant sur une pseudo-prédiction de la totalité du profil de vitesse. Nous évaluerons les performances de la technique proposée en matière de consommation de carburant en la comparant avec une stratégie optimale bénéficiant de la connaissance exacte du profil de vitesse ainsi qu’avec une stratégie de base utilisée couramment dans l’industrie. // Abstract : Since the end of the XXth century, the increase in crude oil price and the environmental concerns lead the automotive industry to develop technologies that can improve fuel savings and decrease greenhouse gases emissions. Among these technologies, the hybrid electric vehicles stand as a reliable and efficient solution. By combining an electrical motor and an internal combustion engine, these vehicles can bring a noticeable improvement in terms of fuel consumption without sacrificing the vehicle autonomy. The two motors and the two energy storage systems require a control unit, called energy management system, which is responsible for the command decision of both motors. The vehicle performances in terms of fuel consumption greatly depend on this control unit. The plug-in hybrid electric vehicles are a more recent technology compared to their non plug-in counterparts. They have an extra internal battery charger that allows the battery to be charged during OFF state, implying a possible discharge during a trip. This particularity adds complexity when it comes to the design of the energy management system. In this thesis, a complete vehicle model is proposed and used for the design of the controller. A study is then carried out to show the dependence between the optimal control of the motors and the speed profile followed during a trip as well as the available electrical energy at the beginning of a trip. According to this study, a self-learning optimization technique that aims at improving the energy management strategy by exploiting some driving data recorded on previous trips is proposed. The technique allows the adaptation of the control strategy to the current trip based on a pseudo-prediction of the total speed profile. Fuel consumption performances for the proposed technique will be evaluated by comparing it with an optimal control strategy that benefits from the exact a priori knowledge of the speed profile as well as a basic strategy commonly used in industry.
273

Designing Energy-Sensitive Interactions : Conceptualising Energy from the Perspective of Electric Cars

Lundström, Anders January 2016 (has links)
As technology is increasingly used in mobile settings, energy and battery management is becoming a part of everyday life. Many have experienced how quickly a battery can be depleted in a smartphone, laptop or electric cars, sometimes causing much distress. An important question is how we can understand and work with energy as a factor in interaction design to enable better experiences for end-users. Through design-oriented research, I have worked with the specific case of electric cars, which is currently a domain where people struggle in terms of energy management. The main issue in this use case is that current driving range estimates cause distrust and anxiety among drivers. Through sketches, prototypes and studies, I investigated causes as well as possible remedies to this situation. My conclusion is that instead of providing black-boxed predictions, in-car interfaces should expose the logics of estimates so that drivers know how their own actions in e.g. driving style, climate control, and other equipment, affects energy use. Revealing such energy mechanisms will not only empower the driver, it will also acknowledge the impact of variables that cannot be predicted automatically. In this work, understanding the dynamic aspects of energy has emerged as central to interaction with systems. This points to a need to design energy sensitive interactions - focusing on supporting users to find the right balance between energy use and the experiential values sought for. To ease design of energy sensitive interactions, energy use is divided into three different categories with accompanying ideals. These are exergy (always needed to achieve the required interaction), intergy (controllable and changing over time and use, needs to be addressed in design), and anergy (always waste that needs to be reduced). This articulation highlights aspects of energy that are specific to interaction design, and possible aspects to expose to allow more energy-efficient interactions in use. / I takt med att vi använder alltmer teknik i mobila sammanhang blir energi- och batterihantering en allt större del av vår vardag. Många har erfarenheter av de besvär som ett plötsligt urladdat batteri i en mobiltelefon, laptop eller elbil kan orsaka. En central fråga för att uppnå bättre användarupplevelser är hur vi kan förstå och arbeta med energi som en faktor i design av interaktion med mobil teknik. Genom designdriven forskning har jag arbetat specifikt med interaktionen i elbilar, en situation där många brottas med just hantering och förståelse av begränsad energi. En specifik utmaning i denna kontext är den misstro som många upplever kring existerande system för räckviddsberäkning. Genom skisser, prototyper och användarstudier har jag undersökt orsaker och praktiska lösningar på detta problem. Min slutsats är att bilens gränssnitt bör exponera den inre logik som beräkningarna bygger på, så att föraren förstår hur egna handlingar, såsom körsätt och användning av t ex kupévärmare, påverkar energiförbrukning och räckvidd. Detta leder till ökad upplevelse av kontroll för föraren, och samtidigt till mer tillförlitliga beräkningar då det tar hänsyn till variabler som inte kan förutsägas automatiskt. I arbetet har dynamiska aspekter av energi framträtt som centralt i användning av interaktiva system. Detta pekar på behovet av att designa energikänsliga interaktioner, som hjälper användaren att förstå balansen mellan energiåtgång och bruksvärde. För att stödja design av energikänsliga interaktioner artikuleras tre kategorier av energianvändning i interaktiva system. Dessa är exergi (behövs för att uppnå tänkt interaktion), intergi (kontrollerbar och föränderlig över tid och användning, måste adresseras med design), och anergi (är alltid ett slöseri som behöver reduceras). Denna artikulation belyser specifikt de aspekter av energiförbrukningen som varierar genom användning, och som skulle kunna exponeras för mer energieffektiv interaktion med ny teknik. / <p>QC 20160429</p>
274

Βελτίωση μετεωρολογικών προγνώσεων με χρήση τεχνητών νευρωνικών δικτύων για τη βελτιστοποίηση συστήματος ενεργειακής διαχείρισης κτιρίων

Θραμπουλίδης, Εμμανουήλ 27 January 2014 (has links)
Σημαντική παράμετρος στο σχεδιασμό των σύγχρονων κτιρίων αποτελεί η ορθολογικότερη διαχείριση της ενέργειας. Η ορθολογικότερη διαχείριση ενέργειας επιτυγχάνεται με το σχεδιασμό κατάλληλων ενεργειακών συστημάτων. Για την αποτελεσματική σχεδίαση αυτών των συστημάτων λαμβάνονται υπόψιν τα μετεωρολογικά δεδομένα, όχι μόνο τα τρέχοντα αλλά και τα προγνωστικά. Τα αριθμητικά πρότυπα πρόγνωσης καιρού παρέχουν εκτιμήσεις των διαφόρων μετεωρολογικών παραμέτρων σε δεδομένα σημεία του χώρου κοντά στην επιφάνεια του εδάφους αλλά και σε διάφορα ύψη. Οι εκτιμήσεις αυτές αποκλίνουν αρκετά από τα πραγματικά δεδομένα γεγονός που παρέχει ένα σημαντικό περιθώριο βελτίωσης της πρόγνωσης. Στην εργασία αυτή προτείνεται μία μέθοδος βελτίωσης της πρόγνωσης μετεωρολογικών δεδομένων με στόχο την αξιοποίηση τους για βελτιστοποίηση της ενεργειακής κατανάλωσης κτιρίου. Η μέθοδος αναπτύχθηκε χρησιμοποιώντας μετρήσεις της ταχύτητας του ανέμου από το μετεωρολογικό σταθμό του Εργαστηρίου Φυσικής της Ατμόσφαιρας του Τμήματος Φυσικής του Πανεπιστημίου Πατρών (ΕΦΑΠ2), καθώς και προγνώσεις του ΕΦΑΠ2 μέσω του αριθμητικού προτύπου πρόγνωσης καιρού WRF (Weather Research and Forecasting model) στο πλησιέστερο δυνατό πλεγματικό σημείο. . Η μέθοδος που προτείνεται, αξιοποιεί τα τεχνητά νευρωνικά δίκτυα και όντας ανεξάρτητη της φύσης της εισόδου μπορεί να χρησιμοποιηθεί για τη βελτίωση της πρόγνωσης μετεωρολογικών παραμέτρων. Επιπλέον, μελετήθηκε η συνεισφορά της μεθόδου στον ακριβέστερο υπολογισμό της ροής αέρα, η οποία υπολογίζεται για ένα πειραματικό θάλαμο δοκιμών, ο οποίος έχει υιοθετηθεί από την Ευρωπαϊκή επιτροπή για την εναρμονισμένη μελέτη ενεργειακών συστημάτων κτιρίων υπό πραγματικές συνθήκες. / An important consideration in the design of modern buildings is the rational use of energy. The rational energy management is achieved by designing appropriate energy systems. For efficient design of these systems we should take into account the meteorological data, not only current but also predictive.Numerical weather prediction models provide estimates of various meteorological parameters to data points of space near the surface and at various heights. These estimates differ considerably from the actual data which provides a significant margin improvement of prognosis. In this work we propose a method of improving the prediction of meteorological data to exploit them to optimize energy consumption in building management systems. The method was developed using measurements of wind speed, from the meteorological station of the Laboratory of Atmospheric Physics of the Department of Physics of the University of Patras (LAPUP), and prognostications LAPUP through numerical weather prediction model WRF (Weather Research and Forecasting model) to the closest possible lattice point. The proposed method utilizes the artificial neural networks and being independent of the nature of the inputs it can be used to improve forecasting meteorological parameters. Furthermore, we studied the contribution of the method to accurately calculate the air flow of an experimental test chamber, which has been adopted by the European Committee for the study of building management systems under real conditions.
275

Impact assessment of energy-efficient lighting interventions

Jakoef, Adiel 12 1900 (has links)
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: Energy-efficient (EE) lighting projects form a substantial percentage of Demand Side Management (DSM) initiatives. These largely entail the exchange of one lighting technology for another more energy-efficient lighting technology. The DSM process typically involves a proposal from an Energy Services Company (ESCO) to retrofit an existing lighting technology with another on the property of a third party, the client. For scoping purposes, ESCOs perform energy savings calculations based on information obtained from the datasheets of the relevant lighting technologies. Such datasheet specifications rarely incorporate the effects of supply voltage fluctuations on energy consumption, which can impact on the accuracy of the savings calculations. Furthermore, modern EE lighting technologies such as Compact Fluorescent lamps (CFLs) employ power electronic circuitry that can in principle give rise to Quality of Supply (QoS) problems such as harmonic distortion. The usage profiles of artificial light fittings targeted in DSM interventions represent another important factor in determining the savings impacts of such projects. There is currently limited information on methodologies for obtaining such usage profiles. In practice, the scoping and impact verification of EE lighting projects are conducted using project-specific applications and spreadsheets that are time-consuming and error-prone. In view of the above-mentioned considerations, this investigation aims to address the lack of voltage-dependent energy consumption data and QoS impacts by conducting a laboratory investigation for all relevant lighting technologies, namely incandescent lamps, CFLs, tubular fluorescent lamps and high intensity discharge lamps. Appropriate mathematical models for the voltage-dependent energy consumption characteristics of these light technologies are derived from the measurements. The supply current harmonic distortion associated with the various lamp types are investigated, particularly with regard to neutral current loading caused by zero-sequence harmonics. Methodologies for obtaining accurate and reliable light usage data using commercially available data loggers are reviewed. A database structure is subsequently designed and implemented to store the information relevant for impact assessment, including the mathematical models of energy consumption, supply voltage profiles and light usage profiles. Finally, an Integrated Software Program (ISP) is developed to implement a methodology for assessing the savings impacts of practical EE lighting projects, using the database as the main input source. The ISP is tested by implementing a real case study. It is shown that the ISP yields accurate results for the case study considered in the evaluation. / AFRIKAANSE OPSOMMING: Energiedoeltreffende (ED) beligtingsprojekte vorm ‟n wesenlike persentasie van vraagkantbestuur (VKB) inisiatiewe. Dit het grootliks te doen met die vervanging van een beligtingstegnologie met ‟n ander meer energiedoeltreffende beligtingstegnologie. Die VKB proses behels normaalweg ‟n voorstel van Energie Dienste Maatskappy (EDM) om ‟n bestaande beligtingstegnologie te vervang met ‟n ander op die perseel van ‟n derde party, die kliënt. EDMs doen energiebesparingsberekeninge op grond van tegniese inligting wat vanaf die datablaaie van die betrokke beligtingstegnologieë verkry word. Hierdie datablad spesifikasies maak selde voorsiening vir die uitwerking van toevoerspanningfluktuasies op energieverbruik, wat die akkuraatheid van die besparingsberekeninge kan beïnvloed. Moderne ED beligtingstegnologieë soos kompakte fluoresseerlampe maak verder gebruik van drywingselektronika stroombane wat in beginsel kan lei tot kwaliteit van toevoer (KVT) probleme soos harmoniese distorsie. Die gebruiksprofiele van kunsmatige lig verteenwoordig nog ‟n belangrike faktor wat die besparingsimpakte van VKB projekte bepaal. Daar is tans beperkte informasie oor die metodologie om sulke gebruiksprofiele te verkry. In die praktyk word die verifiëring van die impak van ED beligtingsprojekte gedoen deur gebruik te maak van projekspesifieke programme en sigblaaie wat tydrowend is en geneig is om te lei tot foute. In die lig van die bogenoemde oorwegings, streef hierdie ondersoek om die tekort aan spanningsafhanklike energieverbruiksdata en KVT impakte te aan te spreek deur „n laboratorium ondersoek uit te voer vir al die relevante beligtingstegnologieë, naamlik filament lampe, kompakte fluoresseerlampe, buisvormige fluoresseerlampe en hoë-intensiteit ontladingslampe. Gepaste wiskundige modelle vir die spanningsafhanklikeenergieverbruik eienskappe van hierdie beligtingstegnologieë word vanuit die metings afgelei. Die harmoniese vervorming van die toevoerstroom van die verskillende beligtingstegnologieë word ondersoek, veral met verwysing tot neutraalstroombelasting wat veroorsaak word deur zero volgorde harmoniese ordes. Metodologieë vir die verkryging van akkurate en betroubare ligverbruikprofiele deur die gebruik van komersieel beskikbare dataversamelaars is nagegaan. ͗n Databasis struktuur is vervolgens ontwerp en geïmplementeer om die toepaslike inligting vir bepaling van die impakte te stoor, insluitend die wiskundige modelle vir energieverbruik, toevoerspanning-en ligverbruikprofiele. ‟n Geïntegreerdesagtewareprogram (GSP) is ontwerp om die metodologie vir die bepaling van besparingsimpakte van praktiese ED beligtingsprojekte te implimenteer, deur gebruik te maak die databasis as die hoofbron van insette. Die GSP is getoets deur ‟n werklike gevallestudie te implimenteer. Daar is bewys dat die GSP akkurate resultate lewer vir die gevallestudie wat in die evaluering gebruik is.
276

Active human intelligence for smart grid (AHISG) : feedback control of remote power systems.

Fulhu, Miraz Mohamed January 2014 (has links)
Fuel supply issues are a major concern in remote island communities and this is an engineering field that needs to be analyzed in detail for transition to sustainable energy systems. Power generation in remote communities such as the islands of the Maldives relies on power generation systems primarily dependent on diesel generators. As a consequence, power generation is easily disrupted by factors such as the delay in transportation of diesel or rises in fuel price, which limits shipment quantity. People living in remote communities experience power outages often, but find them just as disruptive as people who are connected to national power grids. The use of renewable energy sources could help to improve this situation, however, such systems require huge initial investments. Remote power systems often operate with the help of financial support from profit-making private agencies and government funding. Therefore, investing in such hybrid systems is uncommon. Current electrical power generation systems operating in remote communities adopt an open loop control system, where the power supplier generates power according to customer demand. In the event of generation constraints, the supplier has no choice but to limit the power supplied and this often results in power cuts. Most smart grids that are being established in developed grids adopt a closed loop feedback control system. The smart grids integrated with demand side management tools enable the power supplier to keep customers informed about their daily energy consumption. Electric utility companies use different demand response techniques to achieve peak energy demand reduction by eliciting behavior change. Their feedback information is commonly based on factors such as cost of energy, environmental concerns (carbon dioxide intensity) and the risk of black-outs due to peak loads. However, there is no information available on the significant link between the constraints in resources and the feedback to the customers. In resource-constrained power grids such as those in remote areas, there is a critical relationship between customer demand and the availability of power generation resources. This thesis develops a feedback control strategy that can be adopted by the electrical power suppliers to manage a resource-constrained remote electric power grid such that the most essential load requirements of the customers are always met. The control design introduces a new concept of demand response called participatory demand response (PDR). PDR technique involves cooperative behavior of the entire community to achieve quality of life objectives. It proposes the idea that if customers understand the level of constraint faced by the supplier, they will voluntarily participate in managing their loads, rather than just responding to a rise in the cost of energy. Implementation of the PDR design in a mini-grid consists of four main steps. First, the end-use loads have to be characterized using energy audits, and then they have to be classified further into three different levels of essentiality. Second, the utility records have to be obtained and the hourly variation factors for the appliances have to be calculated. Third, the reference demand curves have to be generated. Finally, the operator control system has to be designed and applied to train the utility operators. A PDR case study was conducted in the Maldives, on the island of Fenfushi. The results show that a significant reduction in energy use was achieved by implementing the PDR design on the island. The overall results from five different constraint scenarios practiced on the island showed that during medium constrained situations, load reductions varied between 4.5kW (5.8%) and 7.7kW (11.3%). A reduction of as much as 10.7kW (15%) was achieved from the community during a severely constrained situation.
277

An Approach for Reducing Energy Consumption in Factories by Providing Suitable Energy Efficiency Measures

Krones, Manuela, Müller, Egon 16 September 2014 (has links) (PDF)
Energy efficiency has developed into an important objective for industrial enterprises. However, there is still a need for systematic approaches to reduce energy consumption in factories. Existing methods focus on the optimization of manufacturing processes and lack upon considering the entire factory system. Additionally, they are based on a detailed quantitative analysis of processes and thus, they need a high effort during the phase of data acquisition. Therefore, an approach for reducing energy consumption by providing energy efficiency measures to factory planning participants was developed in order to overcome these barriers. The general approach is described in this paper and supported with a use case that demonstrates the required information and possible outcomes in terms of energy efficiency information. Main advantages of this approach are reducing the effort to acquire energy data and the possibility to consider the factory system holistically.
278

Modellgestützte Dokumentation und Integration von Managementsystemen / Model-based Documentation and Integration of Management Systems

Rößler, Richard 05 October 2016 (has links) (PDF)
Im Sinne einer nachhaltigen und ganzheitlichen Firmenentwicklung lässt sich in der Unternehmenslandschaft ein Trend in Richtung einer kontinuierlichen Erweiterung des unternehmerischen Zielsystems beobachten. Neben etablierten Aspekten, wie dem Qualitätsmanagement und der Arbeitssicherheit, erlangen weitere Themen, wie beispielsweise das betriebliche Umwelt- und Energiemanagement, zunehmend an Bedeutung. Um die Berücksichtigung dieser Aspekte nachzuweisen, steht Unternehmen die Möglichkeit zur Zertifizierung nach funktionsspezifischen Managementsystemnormen offen. Die Einführung und Dokumentation entsprechender Managementsysteme erweist sich jedoch als ein zeitintensiver Prozess, dessen Schwierigkeit vor allem in der unternehmensspezifischen Interpretation der allgemein formulierten Normanforderungen liegt. Strebt ein Unternehmen die Zertifizierung nach mehreren Managementsystemnormen an, so eröffnet sich die Möglichkeit zur Integration der Managementsysteme. Allerdings sind auch die Aufgaben der Integration durch verschiedene Herausforderungen gekennzeichnet, die den Bedarf nach einer systematischen Unterstützung verdeutlichen. Im Bereich der Wirtschaftsinformatik haben sich konzeptuelle Modelle als Instrument zur zielorientierten und verständlichen Beschreibung komplexer Informationssysteme etabliert. Entsprechende Modelle können die Durchdringung und Kommunikation komplexer Sachverhalte durch eine zweckmäßige Abstraktion und Strukturierung vereinfachen und eine Überführung in Anwendungssoftware vorbereiten. Für die vorliegende Dissertation leitet sich unter Berücksichtigung dieser Aspekte folgende zentrale Forschungsfrage ab: Wie kann die konzeptuelle Modellierung bei den Aufgaben der Dokumentation und Integration standardisierter Managementsysteme unterstützen? Der Forschungsmethode des Design Science Research folgend, präsentiert die vorliegende Arbeit funktionsspezifische und funktionsunspezifische Artefakte, die bei der Dokumentation standardisierter Managementsysteme und deren Integration modellbasiert unterstützen. Die Anwendbarkeit der Artefakte wird anhand eines realen Anwendungsfalls demonstriert. Die Ausführungen der vorliegenden Arbeit basieren auf einer Analyse der Anforderungen nach ISO 9001 für Qualitätsmanagementsysteme, ISO 14001 für Umweltmanagementsysteme, ISO 50001 für Energiemanagementsysteme, OHSAS 18001 für Arbeitsschutz- und Arbeitssicherheitsmanagementsysteme sowie des durch die Internationale Organisation für Standardisierung veröffentlichten Annex SL.
279

Modellbasierte Entwicklung von Energiemanagement-Methoden für Flugzeug-Energiesysteme

Schlabe, Daniel 26 January 2017 (has links) (PDF)
Ein geringer Treibstoffverbrauch ist aufgrund von ökologischen und ökonomischen Zielen für die zivile Luftfahrt von großer Bedeutung. Daher werden seit Jahrzehnten konventionell hydraulisch oder pneumatisch betriebene Flugzeugsysteme durch elektrisch betriebene Systeme ersetzt. Dieser Trend wird auch als „More Electric Aircraft (MEA)“ bezeichnet. In bisherigen Studien waren MEA-Architekturen zwar effizienter, jedoch deutlich schwerer als die konventionellen Architekturen. Basierend auf ökonomischen Modellen wird in der vorliegenden Arbeit die modellbasierte Entwicklung eines intelligenten Energiemanagements für Flugzeug-Energiesysteme demonstriert. Das Energiemanagement ermöglicht eine deutliche Reduktion der Systemmasse, verbessert die Energieeffizienz und kann damit den Treibstoffverbrauch eines MEA beträchtlich reduzieren. Insbesondere durch die integrierte und frühzeitige Entwicklung des Energiemanagements mit dem elektrischen System in der Modellbeschreibungssprache Modelica lassen sich die Systemkomponenten mit realistischen Lastprofilen dimensionieren und dadurch die Systemmasse reduzieren. Anhand eines elektrischen Referenzsystems wird das Optimierungspotenzial des Energiemanagements bezüglich Massenreduktion und Energieeffizienzsteigerung quantifiziert und am Systemmodell validiert. Es ergibt sich für das Systemmodell eine Reduktion der Systemmasse um 32 % sowie eine leichte Verbesserung der Energieeffizienz. Durch die multiphysikalische Implementierung des Energiemanagements lässt sich dieses auch für das thermische Management im Flugzeug verwenden. Hierbei kann eine deutliche Verbesserung der Energieeffizienz für die Bereitstellung von Kühlleistung erzielt werden. Aufgrund der erreichten Vorteile sollte ein Energiemanagement bei der Entwicklung zukünftiger Flugzeugenergiesysteme in Betracht gezogen werden. Insbesondere beim MEA existiert ein großes Optimierungspotenzial durch das Energiemanagement. Die Ausführungen in der vorliegenden Arbeit sollen als Motivation für die Flugzeugindustrie dienen, mit realistischen Lastprofilen zu dimensionieren und die modellbasierte und integrierte Entwicklung eines Energiemanagements mit den Energiesystemen bereits in frühen Entwicklungsphasen durchzuführen. / Low fuel consumption is a major concern in civil aerospace due to environmental and economic objectives. Hence, conventional hydraulically or pneumatically driven aircraft systems have been replaced by electrically driven systems for decades. This trend is also known as More Electric Aircraft (MEA). In former studies, MEA architectures were more efficient, but much heavier than their conventional counterparts. The present work demonstrates the model-based development of intelligent energy management algorithms for aircraft energy systems based on economic models. This energy management facilitates a significant reduction of system mass, improves energy efficiency and can hence reduce fuel consumption of MEA considerably. In particular, the integrated development of an energy management along with the electrical system in the Modelica modelling language enables sizing of system components with realistic load profiles. Hence, this reduces the system mass. The optimization potential of the energy management is quantified and validated by means of an electrical reference system model. Applying the energy management, the mass of this system model can be reduced by 32 % and the energy efficiency can be improved slightly. Due to the multi-physical modelling of the energy management, it can also be applied to thermal management of aircraft systems. Thus, the energy efficiency of the cooling system can be improved significantly. As a result of the demonstrated benefits, an energy management should be considered for future development of aircraft energy systems. Especially for MEA, there is tremendous optimization potential for the energy management. Hence, the present work shall motivate aircraft industry to size aircraft systems with realistic load profiles and perform a model-based and integrated development of the energy management along with the electrical system in early phases of the system design process.
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Advanced controllers for building energy management systems : advanced controllers based on traditional mathematical methods (MIMO P+I, state-space, adaptive solutions with constraints) and intelligent solutions (fuzzy logic and genetic algorithms) are investigated for humidifying, ventilating and air-conditioning applications

Ghazali, Abu Baker Mhd January 1996 (has links)
This thesis presents the design and implementation of control strategies for building energy management systems (BEMS). The controllers considered include the multi PI-loop controllers, state-space designs, constrained input and output MIMO adaptive controllers, fuzzy logic solutions and genetic algorithm techniques. The control performances of the designs developed using the various methods based on aspects such as regulation errors squared, energy consumptions and the settling periods are investigated for different designs. The aim of the control strategy is to regulate the room temperature and the humidity to required comfort levels. In this study the building system under study is a 3 input/ 2 output system subject to external disturbances/effects. The three inputs are heating, cooling and humidification, and the 2 outputs are room air temperature and relative humidity. The external disturbances consist of climatic effects and other stochastic influences. The study is carried out within a simulation environment using the mathematical model of the test room at Loughborough University and the designed control solutions are verified through experimental trials using the full-scale BMS facility at the University of Bradford.

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