TY - JOUR A1 - Kral, Christian A1 - Haumer, Anton A1 - Lee, Sang Bin T1 - A Practical Thermal Model for the Estimation of Permanent Magnet and Stator Winding Temperatures JF - IEEE Transactions on Power Electronics N2 - A thermal model for the determination of the temperatures of interior permanent magnets and stator windings is presented in this paper. The innovation of the model relies on one temperature sensor being located in the stator core of the machine. Such sensor is simple to implement in many applications such as traction or EV, where reliability is critical. The estimated stator winding and permanent magnet temperatures are determined by a simplified thermal lumped element network model with only two time constants. It is shown that the proposed thermal model is very robust due to the structure of the model and the measured stator core temperature. The distortion of the temperature estimates caused by the cooling circuit is inherently accounted for such that the model can be used for robust online prediction of temperatures. Experimental results based on a forced water-cooled interior permanent magnet synchronous machine setup are presented to validate the effectiveness of the presented model. KW - cooling KW - lumped element thermal equivalent circuit model KW - magnetic cores KW - permanent magnet machines KW - permanent magnet synchronous machine KW - stators KW - synchronous machines KW - temperature estimation KW - variable speed KW - dynamic load Y1 - 2014 U6 - https://doi.org/10.1109/TPEL.2013.2253128 SN - 1941-0107 SN - 0885-8993 VL - 29 IS - 1 SP - 455 EP - 464 PB - IEEE ER - TY - CHAP A1 - Haumer, Anton A1 - Kral, Christian T1 - The New EDrives Library: A Modular Tool for Engineering of Electric Drives T2 - Proceedings of the 10th International Modelica Conference, March 10-12, 2014, Lund, Sweden N2 - Simulation is an indispensable tool for the engineering of systems containing electric drives. Depending on the design phase and the engineering task different levels of modeling details are required: proof of concept; investigation of energy and power consumption; design of control; etc. The new EDrives library provides three levels of abstraction for inverters: quasi static (neglecting electrical transients); averaging (neglecting switching effects) and switching – for serving different demands. The inverters can feed the machine models of the Modelica Standard Library: Modelica.Magnetic.FundamentalWave and the new Modelica.Magnetic.QuasiStatic.FundamentalWave. The EDrives library copes with arbitrary phase numbers and can be easily extended to develop new control algorithms. In this publication the structure of the library and the implemented control principles are presented. Furthermore; examples comparing the three different levels of abstraction are included. KW - control KW - Electric machines and drives KW - multi phase KW - power electronics KW - quasi static KW - switching KW - thermal behavior KW - transient Y1 - 2014 SN - 978-91-7519-380-9 U6 - https://doi.org/10.3384/ecp14096155 SN - 1650-3686 SN - 1650-3740 SP - 155 EP - 163 PB - Linköping University Electronic Press ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton A1 - Wöhrnschimmel, Reinhard T1 - Extension of the FundamentalWave Library towards Multi Phase Electric Machine Models T2 - Proceedings of the 10th International Modelica Conference, March 10-12, 2014, Lund, Sweden N2 - Abstract Electric machine theory and electric machine simulations models are often limited to three phases. Up to the Modelica Standard Libray (MSL) version 3.2 the provided machine models were limited to three phases. Particularly for large industrial drives and for redundancy reasons in electric vehicles and aircrafts multi phase electric machines are demanded. In the MSL 3.2.1 an extension of the existing FundamentalWave library has been performed to cope with phase numbers greater than or equal to three. The developed machine models are fully incorporating the multi phase electric; magnetic; rotational and thermal domain. In this publication the theoretical background of the machines models; Modelica implementation details; the parametrization of the models and simulation examples are presented. KW - electric Machine models KW - induction machine KW - Modelica Standard Library KW - multi phase KW - synchronous machine KW - synchronous reluctance machine Y1 - 2014 SN - 978-91-7519-380-9 U6 - https://doi.org/10.3384/ecp14096135 SN - 1650-3686 SN - 1650-3740 SP - 135 EP - 143 PB - Linköping University Electronic Press ER - TY - CHAP A1 - Kaspar, Marcel A1 - Rabl, Hans-Peter A1 - Mayer, Wolfgang T1 - Differenzierte Kohlenwasserstoffanalytik im Dieselabgas bei verschiedenen Motorbetriebszustaenden : Detailed hydrocarbon analysis of diesel exhaust gas at different engine operating conditions T2 - 12. FAD-Konferenz „Herausforderung – Agbasnachbehandlung für Dieselmotoren“, 12, 2014, Dresden N2 - Beitrag und Praesentationsmaterial eines Vortrags ueber differenzierende Kohlenwasserstoffanalytik im Dieselabgas bei verschiedenen Motorbetriebszustaenden. Mit einem neu entwickelten, hochgenauen HC-Sensor werden unverbrannte HC im Abgas untersucht. Die differenzierende Untersuchung erfolgt an einem Massenspektrometer, das mit chemischer Ionisation arbeitet. Die Molekuele Ethin, Ethen und Propen wurden gezielt betrachtet. Es zeigt sich, dass bei kalten Betriebsbedingungen diese drei Komponenten etwa die Haelfte der gesamten HC Konzentration ergeben. Ein weiterer Punkt ist die Regeneration des Dieselpartikelfilters. KW - ABGASKONZENTRATION KW - ABGASTRENNUNG KW - ABGASZUSAMMENSETZUNG KW - DIESELMOTOR KW - EINSTUFENFILTER KW - GASFILTER KW - HAUPTSTROMFILTER KW - KATALYTISCHE ABGASNACHVERBRENNUNG KW - KATALYTISCHER REAKTOR KW - KOHLENWASSERSTOFF (ABGAS) KW - OXIDATIONSKATALYSATORANLAGE KW - Partikelfilter KW - PERIODISCH ZU REINIGENDER FILTER KW - R4-MOTOR KW - UEBERDRUCKFILTER Y1 - 2014 SP - 1 EP - 35 PB - Förderkreis Abgasnachbehandlungstechnologien für Verbrennungskraftmaschinen (FAD) e.V. CY - Dresden ER - TY - BOOK A1 - Rill, Georg A1 - Schaeffer, Thomas T1 - Grundlagen und Methodik der Mehrkörpersimulation : Vertieft in Matlab-Beispielen, Übungen und Anwendungen N2 - Dieses Lehrbuch vermittelt nicht nur Grundlagen, sondern stellt auch die Methoden der Mehrkörpersimulation anschaulich dar und erläutert an einfachen Beispielen die Vor- und Nachteile bei der praktischen Anwendung. In den Text integrierte Matlab-Skripte und -Funktionen verdeutlichen die einzelnen Methoden und ermöglichen es, Aufwand und Problematik bei der Umsetzung der Theorie innerhalb von Simulationsprogrammen einzuschätzen. Die Modellbildung, die mathematische Beschreibung und die numerische Simulation von Systemen starrer Körper bilden dabei die Schwerpunkte. Konkret behandelte Beispiele sind die Eigendynamik eines Traktors mit gefederter Vorderachse, das Rotorblatt eines Hubschraubers sowie die Vorderachse eines Pkws. Die entsprechenden Matlab-Skripte und Lösungen zu den Übungsaufgaben können auf der Springer-Homepage beim Buch heruntergeladen werden. Der Inhalt Dynamik des starren Körpers - Bewegungsgleichungen - Starre Körper mit elastischen und kinematischen Verbindungselementen - Integrationsverfahren - Rekursiver Algorithmus - Differential-Algebraische Gleichungen - Analyse von Mehrkörpersystemen - Anwendungs- und Übungsbeispiele aus der Technik Die Zielgruppen Studenten des Maschinenbaus, der Elektrotechnik und Mechatronik sowie der Biomechanik an Hochschulen und Universitäten Ingenieure in der Praxis, die sich mit Fragestellungen der Mehrkörpersimulation (MKS) befassen Entwickler aus der Kfz-Technik sowie Fachleute aus F+E Die Autoren Dr.-Ing. Georg Rill ist Professor mit den Lehrgebieten Technische Mechanik, Ingenieurinformatik, Fahrdynamik, Mehrkörperdynamik sowie Laborleiter Fahrdynamik. Dr.-Ing. Thomas Schaeffer ist Professor mit den Lehrgebieten Konstruktion, CAD, Maschinenelemente und Getriebetechnik, Mehrkörpersysteme und Bewegungstechnik sowie Laborleiter Mehrkörpersimulation, beide an der Ostbayerischen Technischen Hochschule (OTH) Regensburg. Y1 - 2014 U6 - https://doi.org/10.1007/978-3-658-06084-8 PB - Springer CY - Berlin ER - TY - THES A1 - Urban, Johannes T1 - Photoelektrisches Direktladen von Elektrofahrzeugen im Inselbetrieb N2 - Die Arbeit befasst sich mit der Ladung von Elektrofahrzeugen durch Solarenergie in einem Inselsystem. Diese Art der Ladung entlastet die Netze und hat einen sehr hohen Leistungswirkungsgrad. Es wurde ein Prototyp einer Direkt-ladestation gebaut, welche verschiedene Elektrofahrzeuge mit einem neuartigen Verfahren aufladen kann. Sie enthält einen optionalen Pufferakkumulator und einen Vollbrücken-Gegentaktwandler für die Ladung bei schlechter Solarleistung. Ein Teil der Arbeit behandelt ausführlich die Auslegung, die Komponenten und bisher undokumentiertes Verhalten von Gegentaktwandlern. Des Weiteren wird das Prinzip der Solardirekt-ladung und deren Umsetzung sowie die Umsetzung des Gesamtsystems beschrieben. Es folgt ein Kapitel zur Wirtschaftlichkeit der Solardirektladung mit Handlungsempfehlungen. Insgesamt lässt sich schließen, dass Solardirektladung bei nutzungsorientierter Auslegung der Anlage und langer Laufzeit wirtschaftlich ist. This work addresses the charging of electric vehicles with solar power in an off-grid system. Charging this way reduces the stress on the grid and has a very high power efficiency. A prototype of a direct charging station was built which is able to charge several different electric vehicles in a novel way. It includes an optional buffer battery and a full bridge converter for being able to charge electric vehicles at times o flow solar power. One chapter explains in detail the design, the components and so far undocumented properties of full and half bridge converters. The principle and the implementation of direct solar charging and the implementation of the whole system is described. The last chapter covers the cost effectiveness of solar chargin gas well as recommendations. All in all it can be stated that solar direct charging is ecomomically advantageous if it is projected according to the user’s demand. KW - Fotovoltaik KW - Stromtankstelle KW - Elektrofahrzeug KW - Pufferspeicher KW - Photovoltaik KW - Ladestation KW - Elektrofahrzeug KW - Pufferspeicher KW - Vollbrückenwandler Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-20285 ER - TY - CHAP A1 - Völling, Alexander A1 - Nonn, Aida A1 - Schneider, Ingo T1 - Anwendung des Kohäsivzonenmodells zur Abbildung von duktilem dynamischen Rissfortschritt in Gasfernleitungen T2 - 45. Tagung des AK Bruch, Berlin, Germany KW - Ferngasleitung KW - Rissfortschritt Y1 - 2013 SP - 253 EP - 262 ER - TY - CHAP A1 - Nonn, Aida A1 - Kalwa, Christoph T1 - Analysis of dynamic ductile fracture propagation in pipeline steels BT - a damage mechanics approach T2 - 6th Pipeline Technology Conference (2013), Ostend, Belgium N2 - Analysis of dynamic ductile fracture propagation in pipeline steels: a damage-T IS A WELL-ESTABLISHED fact that the successful application of new generation of high-strength steel grades for long-distance gas transmission depends strongly on full understanding and appropriate characterization of fracture resistance. A damage mechanics approach has found to be a very promising tool in supporting the experimental characterization of ductile fracture propagation. The major advantage of this approach lies in the consideration of the influence of local stress and strain variables on the damage evolution and thus its capability to describe the fracture resistance of the pipelines with different stress triaxiality level by using the same set of parameters. However, the wider application of this approach has been limited due to the issues such as reliable determination of input parameters and required material properties, mesh size dependence, etc.. The objective of this paper is to characterize dynamic ductile fracture resistance of X65 and X80 pipeline materials and to demonstrate the potential of damage mechanics approach for the simulation of dynamic fracture propagation by using two damage models: (1) Cohesive Zone (CZ) model and (2) Gurson-Tvergaard-Needleman (GTN) model. In the first step, results from quasi-static and dynamic tensile tests are used to describe plasticity in terms of flow curves. The calibration of input parameters for both models is performed by using the load-deformation curves from quasi-static tests on non-standard drop-weight tear (DWT) specimens with pre-fatigued crack. b. In the next step, estimated damage model parameters are verified by means of the dynamic tests on the pressed and Chevron notch DWT specimens. Different amounts of crack growth are established by varying the drop height. The experimental fracture resistance is quantified in terms of J-integral at specific crack length. The numerical results are evaluated with respect to global load-deformation and fracture resistance behavior. Furthermore, damage simulations are applied for quantification of local stress conditions in order to identify the major factors controlling the crack propagation. The results reported here serve as a basis for better understanding of fracture performance in dependences of geometry and material properties. Y1 - 2013 U6 - https://doi.org/10.13140/2.1.4370.3046 ER - TY - CHAP A1 - Nonn, Aida A1 - Kalwa, Christoph T1 - Application of probabilistic fracture mechanics for safety assessment of longitudinally welded linepipes T2 - 6th Pipeline Technology Conference (2013), Ostend, Belgium Y1 - 2013 ER - TY - CHAP A1 - Nonn, Aida A1 - Kalwa, Christoph T1 - Application of damage mechanics approach for crack propagation in pipeline T2 - 19th Biennial Joint Technical Meeting (JTM) on Pipeline Research, April 29 - May 3, 2013, Sydney, Australia Y1 - 2013 ER - TY - CHAP A1 - Nonn, Aida A1 - Wessel, Waldemar A1 - Schmidt, Tanja T1 - Application of finite element analysis for assessment of fracture behavior of modern high toughness seamless pipeline steels T2 - 23rd International Society of Offshore and Polar Engineering 2013 (ISOPE 2013), Anchorage, USA N2 - Fracture behavior of seamless pipeline material X65Q acc. to API 5L has been studied both experimentally and numerically at different loading conditions (quasi-static vs. dynamic) and temperatures. The recent findings have shown difficulties in applying well established methods for determination of transition behavior or prediction of ductile crack arrest for the new generation of high-toughness steels. The irregular fracture performance (e.g. so-called "abnormal inverse fracture" appearance, significant scattering in ductile-to-brittle-transition-temperature region, etc.) suggests that the influence of pipe dimensions, loading parameters, crack initiation resistance as well as testing procedure on the fracture behavior has been neither understood nor properly described. This work aims to shed light on these questions regarding the applicability of conventional methods and to better illuminate most relevant parameters affecting fracture behavior of high toughness steels. To achieve this goal, experimental data basis for analysis of fracture behavior in transition and upper shelf regime has been established by conducting quasi-static fracture mechanics tests and dynamic tests on Battelle Drop Weight Tear (BDWT or DWT) specimens at different temperatures. The evaluation of obtained test results in upper shelf has been additionally complemented by numerical simulation of damage behavior. The results highlight the influence of stress conditions on fracture behavior with reference to pipe dimensions and loading conditions and, subsequently, may be used as a basis for revision of existing design methods. KW - Rissfortschritt KW - Nahtloses Rohr KW - Pipeline KW - Bruchmechanische Prüfung KW - Finite-Elemente-Methode Y1 - 2013 U6 - https://doi.org/10.13140/2.1.4239.2322 ER - TY - CHAP A1 - Zenger, Gerhard A1 - Kenner, Susanne A1 - Volbert, Klaus A1 - Waas, Thomas A1 - Kucera, Markus T1 - Acquiring energy data from a medium-voltage grid for future smart grid solutions: A practical smart grid application example realized by use of cellular communication networks of the 2nd and 3rd generation T2 - Proceedings of the 11th Workshop on Intelligent Solutions in Embedded Systems (WISES), 10-11 Sept. 2013, Pilsen, Czech Republic N2 - In this paper we present a practical example of the use of Cellular Communication standards like GPRS and UMTS in a Smart Grid Application. For a more detailed view we demonstrate a possible implementation of Cellular Communication Technologies in a data acquisition application for the collection of energy indicators in a medium-voltage grid. Furthermore, we show a technical overview of relevant and common mobile communication standards available in Germany. The included theoretical examples, Smart Grid scenarios, presented data and results are based on a research project for intelligent power regulation in medium-voltage grids performed in Regensburg (Germany). It is a joint project' of the University of Applied Sciences Regensburg together with a local energy provider and a manufacturer for distribution network systems. KW - Mobile communication KW - Medium voltage KW - Standards KW - Smart grids KW - Feeds KW - Ground penetrating radar Y1 - 2013 UR - https://ieeexplore.ieee.org/document/6664954 SN - 978-3-00-042899-9 SP - 1 EP - 8 PB - IEEE ER - TY - JOUR A1 - Freni, Angelo A1 - Frazzica, Andrea A1 - Dawoud, Belal A1 - Chmielewski, Stefanie A1 - Calabrese, Luigi A1 - Bonaccorsi, Lucio Maria T1 - Adsorbent coatings for heat pumping applications: Verification of hydrothermal and mechanical stabilities JF - Applied Thermal Engineering N2 - This paper presents novel experimental methods for verification of both hydrothermal and mechanical stabilities of adsorbent coatings. Experiments have been carried out on zeolite-based coatings over aluminum substrates, prepared by a dip-coating technique developed at CNR-ITAE. Hydrothermal aging of several adsorbent coatings is ongoing. Adsorption and structural stability of some samples under test was successfully verified after 35000 aging cycles by isobars measurement and XRD analysis. Mechanical properties of coatings have been evaluated by applying different typologies of static and dynamic mechanical stresses. Results obtained have been compared with those achieved by subjecting adsorbent coatings prepared by Mitsubishi Plastic Incorporation (MPI) to the same characterization protocol. The comparison between the two types of coating returned that MPI coatings posses similar thermal stability and better mechanical strength than CNR-ITAE coatings. KW - Adsorbent coating KW - Adsorption heat pump KW - Hydrothermal stability KW - Mechanical stability Y1 - 2013 U6 - https://doi.org/10.1016/j.applthermaleng.2011.07.010 VL - 50 IS - 2 SP - 1658 EP - 1663 PB - Elsevier ER - TY - JOUR A1 - Dawoud, Belal T1 - Water vapor adsorption kinetics on small and full scale zeolite coated adsorbers; A comparison JF - Applied thermal engineering N2 - A possibility to enhance both heat and mass transfer characteristics of an adsorber heat exchanger is to apply the adsorbent directly to its surface in form of a consolidated layer. As the majority of the available publications on the effect of both coating technology and adsorbent layer thickness on the adsorption kinetics deals with small scale adsorbent samples, the results obtained can only represent the best case design of an adsorber heat exchanger. This article presents, therefore, a comparison between the adsorption kinetics of water vapour on small as well as two different full scale coated adsorber heat exchanger types with AQSOA-Z02 layers of Mitsubishi Plastics Incorporation under quasi isobaric conditions of adsorption heat pumps. The small scale coated samples have a zeolite dry mass of 200 mg and layer thicknesses of 200, 300 and 500 μm while the full scale adsorbers have a coated zeolite mass between 1.5 and 2.5 kg and layer thicknesses of 150, 200, 300, 400 and 500 μm. In the investigated adsorption heat pump module, up to 52.7 and 57.3% of the equilibrium differential water loading measured with the small scale coated substrates have been obtained after an adsorption-evaporation times of 300 and 600 s, respectively. KW - Adsorbent coating KW - Adsorption heat pump KW - Adsorption kinetics KW - AQSOA-Z02 Y1 - 2013 U6 - https://doi.org/10.1016/j.applthermaleng.2011.07.013 VL - 50 IS - 2 SP - 1645 EP - 1651 PB - Elsevier ER - TY - JOUR A1 - Küpper, Carsten A1 - Artmann, Christina A1 - Pischinger, Stefan A1 - Rabl, Hans-Peter T1 - Schmierölverdünnung von direkteinspritzenden Ottomotoren unter Kaltstartrandbedingungen JF - MTZ - Motortechnische Zeitschrift Y1 - 2013 U6 - https://doi.org/10.1007/s35146-013-0208-1 VL - 74 IS - 9 SP - 710 EP - 715 PB - Springer Vieweg CY - Wiesbaden ER - TY - JOUR A1 - Küpper, Carsten A1 - Artmann, Christina A1 - Pischinger, Stefan A1 - Rabl, Hans-Peter T1 - Lube-Oil Dilution of Gasoline Direct-Injection Engines with Ethanol Fuels JF - MTZ worldwide KW - Fuel Ethanol KW - Engine Cold Start KW - Cold Ambient Conditions KW - Fuel Vapor Mass KW - Test Bench Investigations Y1 - 2013 U6 - https://doi.org/10.1007/s38313-013-0090-8 VL - 74 IS - 9 SP - 64 EP - 69 PB - Springer CY - Berlin ER - TY - CHAP A1 - Brückl, Oliver A1 - Krpal, Ondrej A1 - Riepl, Markus T1 - Influence of wind and solar energy on the frequency of switching operations of On-Load Tap-Changers (OLTC) BT - Electric Power Engineering T2 - Proceedings of the 13th International Scientific Conference Electric Power Engineering 2012, EPE 2012; Vol. 2 Y1 - 2012 SP - 719 EP - 722 PB - EPE CY - Brno, Czech Republic ER - TY - CHAP A1 - Nonn, Aida A1 - Kalwa, Christoph T1 - Simulation of ductile crack propagation in high-strength pipeline steel using damage models T2 - 9th International Pipeline Conference 2012 (IPC 2012), Calgary, Canada N2 - The performance of engineering design of high-strength steel pipelines has revealed the necessity to revise current design procedures. Therefore, an improved and detailed comprehension of fracture mechanisms and development of failure prediction tools are required in order to derive new design criteria. In last decades the most successful failure prediction tools for steel structures subjected to various type of loading can be encountered in the field of damage mechanics. This paper aims to describe ductile fracture behavior of high-strength steel pipelines by applying three different damage models, Gurson-Tvergaard-Needelman (GTN), Fracture Locus Curve (FLC) and Cohesive Zone (CZ). These models are evaluated regarding their capability to estimate ductile crack propagation in laboratory specimens and linepipe components without adjusting the calibrated parameters. It can be shown that appropriate parameter sets can be identified to reproduce load-deformation and fracture resistance curves accurately. The strain rate effect on the fracture behavior is examined by dynamic tests on the BDWT specimens. Finally, the shortcomings of the applied models are pointed out with the reference to possible extensions and modifications. Y1 - 2012 U6 - https://doi.org/10.1115/IPC2012-90653 ER - TY - CHAP A1 - Miedl, Christian A1 - Braun, Jürgen T1 - Powertrain and electric system design of a 800-volt all-electric car T2 - European Conference on Nanoelectronics and Embedded Systems for Electric Mobility, eMotion in Smart Cities, 24.-28. September, 2012, Bologna, Italy Y1 - 2012 ER - TY - JOUR A1 - Ostermeier, Daniel A1 - Mottok, Jürgen A1 - Knorr, Christine A1 - Huber, Michael ED - Mottok, Jürgen ED - Ziemann, Olaf T1 - Competence Atlas for Save and Green Road Vehicles in the Electro Mobility Cluster Regensburg JF - Applied Research Conference 2012 (ARC 2012) 25./26. June 2012, Nuremberg Y1 - 2012 SP - 86 EP - 92 ER -