Vorarlberg University of Applied Sciences
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Autonomous demand side management of electric vehicles
No full textDemand-side management approaches that exploit the temporal flexibility of electric vehicles have attracted much attention in recent years due to the increasing market penetration. These demand-side management measures contribute to alleviating the burden on the power system, especially in distribution grids where bottlenecks are more prevalent. Electric vehicles can be defined as an attractive asset for distribution system operators, which have the potential to provide grid services if properly managed. In this thesis, first, a systematic investigation is conducted for two typically employed demand-side management methods reported in the literature: A voltage droop control-based approach and a market-driven approach. Then a control scheme of decentralized autonomous demand side management for electric vehicle charging scheduling which relies on a unidirectionally communicated grid-induced signal is proposed. In all the topics considered, the implications on the distribution grid operation are evaluated using a set of time series load flow simulations performed for representative Austrian distribution grids. Droop control mechanisms are discussed for electric vehicle charging control which requires no communication. The method provides an economically viable solution at all penetrations if electric vehicles charge at low nominal power rates. However, with the current market trends in residential charging equipment especially in the European context where most of the charging equipment is designed for 11 kW charging, the technical feasibility of the method, in the long run, is debatable. As electricity demand strongly correlates with energy prices, a linear optimization algorithm is proposed to minimize charging costs, which uses next-day market prices as the grid-induced incentive function under the assumption of perfect user predictions. The constraints on the state of charge guarantee the energy required for driving is delivered without failure. An average energy cost saving of 30% is realized at all penetrations. Nevertheless, the avalanche effect due to simultaneous charging during low price periods introduces new power peaks exceeding those of uncontrolled charging. This obstructs the grid-friendly integration of electric vehicles
Product-focused software process improvement. 24th International conference, PROFES 2023, Dornbirn, Austria, December 10–13, 2023, Proceedings, Part I
No full textControlling Analytics: Einsatz für Prognosen im Controlling - Teil 1: Fallbeschreibung und Aufgaben
No full textStatistische Methodenkompetenz wird im Controlling zunehmend bedeutender, so ist die evidenzbasierte Prognose durch algorithmische Analyse von Datenbeständen ein Schwerpunkt von Controlling Analytics. Die Fallstudie durchleuchtet daher anhand von Datenmaterial des Schweizer Bundesamts für Statistik das Vorgehen bei einer Datenanalyse, insbesondere beim Einsatz der Zeitregression für Prognosezwecke, und geht dabei auf methodische Besonderheiten, Caveats und Einsatzmöglichkeiten in Microsoft Excel ein
Controlling Analytics: Einsatz für Prognosen im Controlling - Teil 2: Lösungshinweise
No full textStatistische Methodenkompetenz wird im Controlling zunehmend bedeutender, so ist die evidenzbasierte Prognose durch algorithmische Analyse von Datenbeständen ein Schwerpunkt von Controlling Analytics. Die Fallstudie durchleuchtet daher anhand von Datenmaterial des Schweizer Bundesamts für Statistik das Vorgehen bei einer Datenanalyse, insbesondere beim Einsatz der Zeitregression für Prognosezwecke, und geht dabei auf methodische Besonderheiten, Caveats und Einsatzmöglichkeiten in Microsoft Excel ein. Die Fallbeschreibung und Aufgaben sind im WiSt-Heft Nr. 4/23 zu finden
Mittelständische Hoteliers in der digitalen Transformation – Eine nutzwertorientierte Investitionsempfehlung und Priorisierung aktueller Technologietrends basierend auf einer Technologie-Portfolio-Analyse
No full textAutomated simulation-based model optimization of a hydraulic two-wheeler brake control system
Get PDFUntil now, two-wheeler brake control systems of Robert Bosch GmbH are calibrated in a manual process. A complex embedded model emulates the real system and its properties, such as hydraulic stiffness and line lengths, with various calibration parameters and characteristic curves. During the calibration process, the outlet and inlet valve of the system decrease and increase the manually applied pressure in defined pressure profiles. Additionally mounted pressure sensors enable the comparison of the real measured pressure at the wheel caliper with the pressure assumed by the surrogate model. Each requested pressure step must be followed by the exact pressure adaptation in order to ensure the most accurate model-based pre-control during high-frequency anti-lock braking. The validation is done manually and each calibration trial requires a flash process. A complex set of parameters, characteristic curves and objectives can lead to inconsistent calibration results. This study examines the extent to which a new simulation-based optimization approach can automate the described calibration of a hydraulic brake control model. Therefore, the calibration is separated from the measurement process and the surrogate model is implemented in an expandable framework, developed in MATLAB and Simulink by MathWorks. System knowledge is expanded and a multi-dimensional, non-linear and non-smooth behavior of the objective function is identified. Based on the study of different optimization strategies, a so-called patternsearch solver is implemented that minimizes a weighted sum of two objectives. The automation algorithm is first developed for one specific brake system and is then applied to a new brake system. Both validations show promising calibration results. Hence, it is successfully demonstrated that speed, standardization and accuracy of the calibration can be improved. The suitability and potential of simulation-based optimization in brake system calibration is proven. A solid foundation is achieved that can be expanded in various respects for future developments. The validated framework allows further integration and automation possibilities of the calibration tool
Die Weiterbildung Praxisanleitung in Österreich- eine deskriptive Querschnittstudie
Get PDFPraxisanleiter:innen nehmen eine entscheidende Rolle in der Ausbildung von Pflegepersonen wahr. Die Tätigkeit fordert eine Vielzahl von Kompetenzen. Die Weiterbildung Praxisanleitung bietet eine wichtige Grundlage für die Entwicklung dieser Kompetenzen – deren Rahmenbedingungen, Methoden und Inhalte in Österreich werden in dieser Studie untersucht
