PhD presentations: Matthias Rogge, Jeanette Münderlein & Michael Merten

Thursday, July 16, 2020, 08:30 a.m.

The lectures are shown via video stream

 

08:30 a.m. Dipl.-Ing. Matthias Rogge
„Electrification of Public Transport Bus Fleets with Battery Electric Buses – Development of a software toolchain for the changeover planning of entire bus fleets with consideration of technical and operational constraints“

Electric buses are entering public transport bus fleets and introduce a new level of complexity in the strategic planning of public transport operators. Although numerous research activities focus on the field of electrification planning, there is thus far an absence of a comprehensive planning approach for the public transport domain covering all thematic areas, from technical design over operational planning to the assessment of lifecycle costs. The present thesis closes this gap by providing a software-based planning approach whose applicability has been proven through various case studies. The novelty of this approach regards the high level of detail for all planning phases, which is enabled by the developed software toolchain utilizing state-of-the-art simulation and optimization methods as well as interfaces to existing planning software and third-party data. Efficient calculation methods facilitate analysis of large scenarios and a wide range of technical alternatives. The consequences of electrification with battery electric buses are elucidated for all stakeholders involved in the electrification process, such as operational planning and infrastructure departments. Furthermore, aggregated and normalized figures are provided to allow a neutral comparison of technical alternatives.

09:45 a.m. Jeanette Münderlein, M.Sc.
„Thermografische Methoden zur zerstörungsfreien Messung der anisotropen Wärmeleitfähigkeit von Lithium-lonen Zellen“

Bezugnehmend auf die zukünftigen Veränderungen der Energieerzeugung in Deutschland entsteht ein erhöhter technischer Bedarf an flexiblen Versorgungskonzepten. Für eine erfolgreiche Integration neuer Energiekonzepte stellt deren Wirtschaftlichkeit einen ausschlaggebenden Faktor dar. Um bereits in der Planungs- und Auslegungsphase die Grundlagen einer bestmöglichen Profitabilität sicherzustellen, wurde in der vorliegenden Arbeit ein hybrides Speichersystem erarbeitet und grundlagenwissenschaftlich untersucht. Basierend auf der modularen Struktur des Modells wurden verschiedene Technologien kombiniert. Im Detail wurden sowohl ein Lithium-Ionen und ein Blei-Batteriesystem als auch eine “Power-to-Heat“- und eine Wasserstofferzeugungseinheit analysiert. Weiterhin wurden für die jeweiligen Kombinationen intelligente Betriebskonzepte entwickelt. Diese berücksichtigen die differierenden technologischen Charakteristika, wodurch ein positiver Einfluss auf die Wirtschaftlichkeit erzielt werden konnte. Darüber hinaus erfolgte eine Optimierung der Technologien hinsichtlich ihrer Größe. Eine essentielle Voraussetzung der Auslegung des hybriden Modells stellte die Anwendung im Multinutzen-Betrieb auf Grundlage aktueller Marktbedingungen dar.

11:00 a.m. Michael Merten, M. Sc.
„Participation of Battery Storage Systems in the Secondary Control Reserve Market“

Automatic Frequency Restoration Reserve (aFRR) is one of three control reserve services in continental Europe to compensate electrical grid imbalances. With an increasing share of renewable sources, fewer conventional power plants will be available in the future for grid stabilization. However, new technologies are facing various entrance barriers because of the complex market design. This work provides a detailed aFRR market analysis and derives earning potentials for different bidding strategies. In order to assist the creation of bidding strategies, a market prediction methodology is presented. Both statistical and machine learning based models are used for predicting key market quantities. An model comparison reveals a usually better performance of statistical models. Exogenous data sources such as weather, electrical loads or market data did not significantly improve the prediction performance. This work further developed an operating strategy for integrating Battery Energy Storage Systems (BESS) into existing virtual power plants (VPP) in order to exploit the advantages of multiple technologies. Based on an optimization process, a bidding strategy is presented that optimizes the bids to submit to the aFRR auction. An in-depth cost breakdown and battery-ageing model support the derivation of optimal bids. With current costs of containerized BESS, an operation is not economically viable and earnings were found to be lower than on the Frequency Control Reserve (FCR) market. However, with a predicted cost breakdown for the year 2025, profits can be generated.