@incollection{KuechlerSchoberHarreretal., author = {K{\"u}chler, Andreas and Schober, F. and Harrer, S. and Krause, Ch. and Berger, Frank}, title = {Einfluss von Temperatur und Ligningehalt auf die elektrische Leitf{\"a}higkeit von Pressspan als HG{\"U}-Isolierwerkstoff}, series = {6. RCC-Fachtagung „Werkstoffe zur Anwendung in der el. Energietechnik unter den besonderen Anforderungen der HG{\"U}"}, booktitle = {6. RCC-Fachtagung „Werkstoffe zur Anwendung in der el. Energietechnik unter den besonderen Anforderungen der HG{\"U}"}, address = {Berlin}, pages = {268 -- 273}, language = {de} } @incollection{KuechlerSchoberHarreretal., author = {K{\"u}chler, Andreas and Schober, F. and Harrer, S. and Wolfinger, T. and Krause, Ch. and Exner, W. and Berger, Frank}, title = {Leitf{\"a}higkeit von Pressspan als diagnostische Kenngr{\"o}ße f{\"u}r HG{\"U}-Betriebsmittel}, series = {ETG-Fachbericht 144}, booktitle = {ETG-Fachbericht 144}, publisher = {VDE}, address = {Berlin}, language = {de} } @book{Eckert, author = {Eckert, Ludwig}, title = {Ein Beitrag zur Implementierung autonomer, intelligenter und feldbusgest{\"u}tzter Sensor-/Aktorsysteme im Feldbereich (CASE/SA)}, publisher = {VDI}, isbn = {3183571102}, language = {de} } @incollection{Kuechler, author = {K{\"u}chler, Andreas}, title = {Ausbildung und Steuerung elektrischer Felder bei Gleichspannungsbeanspruchung}, series = {6. RCC-Fachtagung „Werkstoffe zur Anwendung in der el. Energietechnik unter den besonderen Anforderungen der HG{\"U}"}, booktitle = {6. RCC-Fachtagung „Werkstoffe zur Anwendung in der el. Energietechnik unter den besonderen Anforderungen der HG{\"U}"}, address = {Berlin}, pages = {12 -- 50}, language = {de} } @incollection{KuechlerReumannWirthetal., author = {K{\"u}chler, Andreas and Reumann, Andreas and Wirth, Isabell and Langens, Achim and Berger, Frank}, title = {Erfassung transienter elektrischer Potentialverteilungen in thermisch hoch belasteten Gleichspannungsdurchf{\"u}hrungen}, series = {ETG-Fachbericht 144}, booktitle = {ETG-Fachbericht 144}, publisher = {VDE}, address = {Berlin}, abstract = {Mit Hilfe kapazitiver Steuerung k{\"o}nnen Durchf{\"u}hrungen hochspannungsf{\"u}hrende Leiter durch geerdete W{\"a}nde in Geb{\"a}uden oder Ger{\"a}ten f{\"u}hren. Bei zeitver{\"a}nderlichen Belastungen (Stoß-, Wechselspannungen) wird die gew{\"u}nschte Potentialaufteilung durch die Kapazit{\"a}ten zwischen den leitf{\"a}higen Steuerbel{\"a}gen erzwungen. Bei Gleichspannung ergibt sich eine resistive Steuerung, die bei homogener Leitf{\"a}higkeit des Isolierk{\"o}rpers eine prinzipiell gleichartige Potentialaufteilung ergibt. Durchf{\"u}hrungen sind jedoch thermisch hoch belastete Betriebsmittel, in denen starke Temperaturgradienten und in ihrer Folge starke Leitf{\"a}higkeitsgradienten entstehen, die zu einer erheblichen Verschiebung der Potentialverteilung f{\"u}hren k{\"o}nnen [1]. F{\"u}r Design und Diagnose ist das Verst{\"a}ndnis dieser bisher nur theoretisch erfassbaren Vorg{\"a}nge von großer Bedeutung. Deshalb wurden f{\"u}r experimentelle Untersuchungen zwei identische Durchf{\"u}hrungsk{\"o}rper hergestellt, die mit Temperaturf{\"u}hlern f{\"u}r thermische Messungen bzw. mit Anzapfungen f{\"u}r die Erfassung von elektrischen Potentialen ausger{\"u}stet wurden. Die identische Beheizung beider Leiterrohre erlaubt es, eine Korrelation gemessener thermischer und elektrischer Profile und Transienten herzustellen. F{\"u}r r{\"u}ckwirkungsfreie Messung der Gleichspannungspotentiale wurde ein Rotationsvoltmeter benutzt. Die Untersuchungen best{\"a}tigen das theoretisch erwartete thermisch-elektrische Verhalten und sie zeigen, dass erhebliche transiente und station{\"a}re elektrische Belastungen auftreten k{\"o}nnen, die im Zusammenhang mit thermischen Transienten und Belastungen gesehen werden m{\"u}ssen. Sie sind beim Design in Rechnung zu stellen und sie zeigen, dass die bei dielektrischen Diagnosemessungen erfassten Materialkenngr{\"o}ßen wichtige Aussagen {\"u}ber den elektrischen Belastungszustand der Durchf{\"u}hrung liefern k{\"o}nnen.}, language = {de} } @incollection{KuechlerHuellmandelAppoldetal., author = {K{\"u}chler, Andreas and H{\"u}llmandel, F. and Appold, M. and Liebschner, M. and Krump, R. and Titze, J.}, title = {Diagnose von Hochspannungsdurchf{\"u}hrungen durch PDC-Analyse}, series = {ETG-Fachbericht 104}, booktitle = {ETG-Fachbericht 104}, publisher = {VDE}, address = {Kassel}, language = {de} } @incollection{KuechlerHuellmandelBoehmetal., author = {K{\"u}chler, Andreas and H{\"u}llmandel, F. and B{\"o}hm, K. and Koch, N.}, title = {Einfluss {\"a}ußerer Grenzfl{\"a}chen auf die dielektrische Diagnose betriebsgealterter Hochspannungsdurchf{\"u}hrungen}, series = {ETG-Fachbericht 99}, booktitle = {ETG-Fachbericht 99}, publisher = {VDE}, address = {Hanau}, language = {de} } @incollection{KuechlerZinkBerger, author = {K{\"u}chler, Andreas and Zink, M. and Berger, Frank}, title = {Kompensation des Temperatureinflusses auf dielektrische Messungen im Zeitbereich zur Beschreibung von Isolierwerkstoffen}, series = {ETG-Fachbericht 140}, booktitle = {ETG-Fachbericht 140}, publisher = {VDE}, address = {Dresden}, language = {de} } @incollection{KuechlerHuellmandelBoehmetal., author = {K{\"u}chler, Andreas and H{\"u}llmandel, F. and B{\"o}hm, K. and Liebschner, M. and Appold, M. and Krump, R. and Titze, J.}, title = {Dielectric Diagnosis and Monitoring of High Voltage Bushings}, series = {51. IWK Int. Wissenschaft}, booktitle = {51. IWK Int. Wissenschaft}, publisher = {Technische Universit{\"a}t Ilmenau}, address = {Ilmenau}, language = {en} } @incollection{KuechlerElliottLavieretal., author = {K{\"u}chler, Andreas and Elliott, F.E. and Lavier, B. and K{\"u}hn, W.}, title = {FEM-Study on converter transformer failures in the Celilo HVDC converter station}, series = {IEEE PES winter power meeting}, booktitle = {IEEE PES winter power meeting}, address = {USA}, language = {en} } @incollection{KuechlerKrumpHaberechtetal., author = {K{\"u}chler, Andreas and Krump, R. and Haberecht, P. and Titze, J. and Liebschner, M.}, title = {Bushings for Highest Voltages}, series = {Highvolt-Kolloquium}, booktitle = {Highvolt-Kolloquium}, address = {Dresden}, language = {en} } @incollection{KuechlerDunzHindereretal., author = {K{\"u}chler, Andreas and Dunz, Th. and Hinderer, A. and Schwab, A.}, title = {Transient Field Distribution Measurments with Electrically Long Sensors}, series = {5th ISH Int. Symp. on High Voltage Engineering}, booktitle = {5th ISH Int. Symp. on High Voltage Engineering}, address = {Braunschweig}, pages = {08 -- 32}, language = {en} } @article{Kaupp, author = {Kaupp, Tobias}, title = {Lehre, Forschung und Transfer am Beispiel der Robotik}, series = {FHWS Science Journal}, volume = {5}, journal = {FHWS Science Journal}, number = {2}, issn = {2196-6095}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:863-opus-20065}, pages = {109 -- 116}, abstract = {Das IDEE ist mit vier Forschungsprofessoren besetzt, die durch eine Lehrentlastung Freir{\"a}ume f{\"u}r den Auf- und Ausbau von interdisziplin{\"a}ren Forschungsaktivit{\"a}ten nutzen k{\"o}nnen. Das Center Robotik (CERI) ist eines der Aufgabengebiete des IDEEs mit den beiden Schwerpunkten »Robotergest{\"u}tzte Arbeitspl{\"a}tze der Zukunft« sowie »Intralogistik in der Smart Factory«. Dieser Artikel besch{\"a}ftigt sich mit dem zweiten Schwerpunkt. Anhand der CERI Aktivit{\"a}ten im Bereich der fahrerlosen Transportsysteme wird aufgezeigt, wie der »Dreiklang« Forschung, Lehre und Transfer in der Praxis umgesetzt wird und die drei Bestandteile sich gegenseitig befruchten k{\"o}nnen.}, language = {de} } @phdthesis{Wirth, author = {Wirth, Isabell}, title = {Ber{\"u}cksichtigung dielektrischer Materialeigenschaften in der Finiten-Elemente-Simulation von HG{\"U}-Isoliersystemen}, series = {Ilmenauer Beitr{\"a}ge zur elektrischen Energiesystem-, Ger{\"a}te- und Anlagentechnik}, journal = {Ilmenauer Beitr{\"a}ge zur elektrischen Energiesystem-, Ger{\"a}te- und Anlagentechnik}, number = {26}, publisher = {Universit{\"a}tsverlag Ilmenau}, address = {Ilmenau}, isbn = {978-3-86360-215-4}, doi = {10.22032/dbt.41185}, pages = {136}, abstract = {Verbrauchsfern erzeugter Strom aus regenerativen Energien kann {\"u}ber große Distanzen am wirtschaftlichsten mittels der Hochspannungsgleichstrom{\"u}bertragung (HG{\"U}) transportiert werden. Die HG{\"U} f{\"u}hrt zu einer ver{\"a}nderten elektrischen Belastung der Hochspannungskomponenten. Transiente {\"U}bergangsvorg{\"a}nge bestimmen die elektrischen Feldverteilungen. Bei der Berechnung elektrischer Feldverteilungen in Isoliersystemen f{\"u}r die Hochspannungsgleichstrom{\"u}bertragung (HG{\"U}) mit Hilfe der Finiten-Elemente-Methode (FEM) wurden die dielektrischen Eigenschaften bisher in Form von Permittivit{\"a}ten und parameterabh{\"a}ngigen Leitf{\"a}higkeiten ber{\"u}cksichtigt. Langsame Polarisationsvorg{\"a}nge werden dabei nicht ber{\"u}cksichtigt. F{\"u}r die Berechnung komplexer Isoliersysteme durch die FEM ist deshalb die Beschreibung der langsamen Polarisationsvorg{\"a}nge im Isolierstoff durch Differentialgleichungen w{\"u}nschenswert, die direkt in die FEM einbezogen werden und mit denen je nach Bedarf sowohl einzelne Polarisationsmechanismen als auch ihre {\"U}berlagerungen ber{\"u}cksichtigt werden k{\"o}nnen. In dieser Arbeit werden hierf{\"u}r auf Basis des bekannten Debye-Ansatzes, und in Analogie zum Netzwerkmodell, zus{\"a}tzlich zu den Gleichungen, die Verschiebungs- und Leitungsstr{\"o}me beschreiben, weitere Differentialgleichungen direkt in die FEM einbezogen, welche die feld- und temperaturabh{\"a}ngigen Polarisationsstr{\"o}me individuell abbilden. Die Materialfunktionen und ihre Parameter werden durch Messung von Polarisations- und Depolarisationsstr{\"o}men (PDC) ermittelt. Durch die Implementierung von beliebigen Polarisationsmechanismen in einem FEM-Programm wurde eine L{\"u}cke der Berechnungsm{\"o}glichkeiten von komplexen, auch dreidimensionalen Isoliersystemen geschlossen, in denen oftmals station{\"a}re oder transiente Temperaturgradienten vorliegen und in denen sich transiente elektrische Feldverteilungen ausbilden. Zur Verifizierung des beschriebenen Berechnungsverfahrens werden transiente Potentialverl{\"a}ufe an den Steuerbel{\"a}gen von entsprechend modifizierten Hochspannungsdurchf{\"u}hrungen unter Gleich- und Umpolspannungen sowie unter thermischen Gradienten gemessen. Dabei kann eine bisher nicht erreichte {\"U}bereinstimmung der transienten und station{\"a}ren Potentialverl{\"a}ufe zwischen FEM-Simulation und Messung erzielt werden. Auswirkungen auf Pr{\"u}f- und Belastungsszenarien werden anhand von Simulationen diskutiert.}, subject = {Hochspannungsgleichstrom{\"u}bertragung}, language = {de} } @misc{Zimmermann, type = {Master Thesis}, author = {Zimmermann, Korbinian}, title = {Verwaltung von Trainingsdaten f{\"u}r K{\"u}nstliche Intelligenz}, school = {Hochschule f{\"u}r Angewandte Wissenschaften W{\"u}rzburg-Schweinfurt}, abstract = {In order to operate a permanent magnet synchronous motor (PSM) as efficiently as possible, it requires precise information about the current thermal state of the electric drive. In most production vehicles, rotor and stator thermocouples are not used for financial reasons. Within the development of a temperature model based on the physical approach, measurements are carried out with a telemetry unit installed in the electric motor. These take place both on the test bench and in the test vehicle. The resulting measurement records give reason to investigate a data-based approach using deep learning, which is the aim of this work. In addition to the evaluation of the existing test bench and vehicle data, the focus is on the development of a neural temperature model. The results obtained will be compared with the existing ECU temperature model.}, language = {de} } @article{MathesSeufert, author = {Mathes, Markus and Seufert, Jochen}, title = {Programmieren in C++ f{\"u}r Elektrotechniker und Mechatroniker}, publisher = {Springer Vieweg}, address = {Wiesbaden}, isbn = {978-3-658-38501-9}, doi = {10.1007/978-3-658-38501-9}, pages = {252}, abstract = {Das Buch Programmieren in C++ f{\"u}r Elektrotechniker und Mechatroniker bietet einen Einstieg in die moderne Softwareentwicklung f{\"u}r Studierende der Ingenieurwissenschaften. Dabei wird ein durchg{\"a}ngiger Ansatz verfolgt, der, beginnend mit den Grundlagen der Programmierung, bis hin zu weiterf{\"u}hrenden Themen, wie Hardware-nahe Programmierung, zahlreiche Themengebiete betrachtet und Studierende nicht nur f{\"u}r die Pr{\"u}fung, sondern auch f{\"u}r den Arbeitsalltag vorbereitet. Da man Programmieren nur durch {\"U}ben erlernen kann, liefert das Buch einen umfangreichen Aufgabenkatalog.}, language = {de} } @article{GustavsenRahimpour, author = {Gustavsen, B. and Rahimpour, Ebrahim}, title = {High-Frequency Transformer and Reactor Models for Network Studies, Part E: Measurements and transformer design details}, series = {Conseil International des Grands R{\´e}seaux {\´E}lectriques (CIGRE) TB 904}, journal = {Conseil International des Grands R{\´e}seaux {\´E}lectriques (CIGRE) TB 904}, isbn = {978-2-8587-3609-6}, pages = {1 -- 140}, language = {en} } @article{GustavsenRahimpour, author = {Gustavsen, B. and Rahimpour, Ebrahim}, title = {High-Frequency Transformer and Reactor Models for Network Studies, Part D: Model interfacing and specifications}, series = {Conseil International des Grands R{\´e}seaux {\´E}lectriques (CIGRE) TB 903}, journal = {Conseil International des Grands R{\´e}seaux {\´E}lectriques (CIGRE) TB 903}, isbn = {978-2-8587-3608-9}, pages = {1 -- 43}, language = {en} } @article{GustavsenRahimpour, author = {Gustavsen, B. and Rahimpour, Ebrahim}, title = {High-Frequency Transformer and Reactor Models for Network Studies, Part B: Black-Box Models}, series = {Conseil International des Grands R{\´e}seaux {\´E}lectriques (CIGRE) TB 901}, journal = {Conseil International des Grands R{\´e}seaux {\´E}lectriques (CIGRE) TB 901}, isbn = {978-2-8587-3606-5}, pages = {1 -- 88}, language = {en} } @article{GustavsenRahimpour, author = {Gustavsen, B. and Rahimpour, Ebrahim}, title = {High-Frequency Transformer and Reactor Models for Network Studies, Part A: White-Box Models}, series = {Conseil International des Grands R{\´e}seaux {\´E}lectriques (CIGRE) TB 900}, journal = {Conseil International des Grands R{\´e}seaux {\´E}lectriques (CIGRE) TB 900}, isbn = {978-2-8587-3605-8}, pages = {1 -- 203}, language = {en} } @book{Kuechler, author = {K{\"u}chler, Andreas}, title = {Erfassung transienter elektromagnetischer Feldverteilungen mit konzentrierten und r{\"a}umlich ausgedehnten Sensoren}, publisher = {VDI}, address = {D{\"u}sseldorf}, language = {de} } @incollection{KuechlerHammerMaeueler, author = {K{\"u}chler, Andreas and Hammer, F. and M{\"a}ueler, G.}, title = {Behaviour of Bushings with Silicone Rubber Sheds}, series = {6th ISH Int. Symp. on High Voltage Engineering}, booktitle = {6th ISH Int. Symp. on High Voltage Engineering}, address = {New Orleans, LA, USA}, pages = {38 -- 47}, language = {en} } @article{HolderEberspaecher, author = {Holder, Marvin Alexander Samuel and Ebersp{\"a}cher, Mark}, title = {Systematic methods for the synthesis of equidistant MIMO arrays}, series = {Advances in Radio Science}, volume = {21}, journal = {Advances in Radio Science}, doi = {10.5194/ars-21-15-2023}, pages = {15 -- 23}, abstract = {Finding a feasible antenna arrangement for multiple input multiple output (MIMO) arrays to serve a specific purpose is a first crucial step towards a successful MIMO radar system design. Design methods to synthesize uniformly weighted and equidistant MIMO arrays are proposed and investigated. The methods can be used to gain a design foundation for 1D or 2D arrays without software tools or programming effort. Since the presented approach does not consider electromagnetic fields, electromagnetic full-wave simulations might be required additionally. The method is based on sequentially copying and displacing antenna groups with the help of a number scheme. A nomenclature is proposed to classify the degrees of freedom in the design procedure. If the antennas are aligned to a uniform grid, a polynomial representation of the array can be chosen alternatively. This method is beneficial when redundancies of a produced array and where they appear must be analyzed. A new design problem arises when an array is to consist of only transceiving antennas, which can be analyzed with polynomial multiplication. One strategy to find a suitable MIMO array consisting of transceiver elements is given and evaluated.}, language = {en} } @article{RoserBirkholdPreuhsetal., author = {Roser, Philipp and Birkhold, Annette and Preuhs, Alexander and Stimpel, Bernhard and Syben, Christopher and Strobel, Norbert and Kowarschik, Markus and Fahrig, Rebecca and Maier, Andreas}, title = {Fully-automatic CT data preparation for interventional X-ray skin dose simulation}, series = {Bildverarbeitung f{\"u}r die Medizin 2020: Algorithmen - Systeme - Anwendungen. Proceedings des Workshops vom 15. bis 17. M{\"a}rz 2020 in Berlin}, journal = {Bildverarbeitung f{\"u}r die Medizin 2020: Algorithmen - Systeme - Anwendungen. Proceedings des Workshops vom 15. bis 17. M{\"a}rz 2020 in Berlin}, publisher = {Springer Fachmedien}, address = {Wiesbaden}, doi = {10.1007/978-3-658-29267-6_26}, pages = {125 -- 130}, language = {en} } @article{BuschStrobelNobachetal., author = {Busch, Erik and Strobel, Norbert and Nobach, Kai and Bulitta, Clemens and Hirshfeld, John W. and Lin, Wu and de Abreu, Marcel Gama}, title = {Optimizing the innovation and development process of medical devices - a study based on angiographic equipment}, series = {Health and Technology}, volume = {11}, journal = {Health and Technology}, number = {3}, doi = {doi.org/10.1007/s12553-021-00537-7}, pages = {563 -- 574}, language = {en} } @article{RoserBirkholdPreuhsetal., author = {Roser, Philipp and Birkhold, Annette and Preuhs, Alexander and Ochs, Philipp and Stepina, Elizaveta and Strobel, Norbert and Kowarschik, Markus and Fahrig, Rebecca and Maier, Andreas}, title = {XDose: toward online cross-validation of experimental and computational X-ray dose estimation}, series = {International Journal of Computer Assisted Radiology and Surgery}, volume = {16}, journal = {International Journal of Computer Assisted Radiology and Surgery}, number = {2}, doi = {10.1007/s11548-020-02298-6}, language = {en} } @article{RoserBirkholdPreuhsetal., author = {Roser, Philipp and Birkhold, Annette and Preuhs, Alexander and Syben, Christopher and Felsner, Lina and Hoppe, Elisabeth and Strobel, Norbert and Kowarschik, Markus and Fahrig, Rebecca and Maier, Andreas}, title = {X-ray Scatter Estimation Using Deep Splines}, series = {IEEE Transactions on Medical Imaging}, volume = {40}, journal = {IEEE Transactions on Medical Imaging}, number = {9}, pages = {2272 -- 2283}, language = {en} } @article{HariharanStrobelKaethneretal., author = {Hariharan, Sai Gokul and Strobel, Norbert and Kaethner, Christian and Kowarschik, Markus and Fahrig, Rebecca and Navab, Nassir}, title = {Data-driven estimation of noise variance stabilization parameters for low-dose x-ray images}, series = {Physics in Medicine and Biology}, volume = {65}, journal = {Physics in Medicine and Biology}, number = {22}, doi = {10.1088/1361-6560/abbc82}, language = {en} } @article{ZhongStrobelBirkholdetal., author = {Zhong, Xia and Strobel, Norbert and Birkhold, Annette and Kowarschik, Markus and Fahrig, Rebecca and Maier, Andreas}, title = {A machine learning pipeline for internal anatomical landmark embedding based on a patient surface model}, series = {International Journal of Computer Assisted Radiology and Surgery}, volume = {14}, journal = {International Journal of Computer Assisted Radiology and Surgery}, number = {1}, doi = {10.1007/s11548-018-1871-y}, pages = {53 -- 61}, language = {en} } @article{ShettyBirkholdJaganathanetal., author = {Shetty, Karthik and Birkhold, Annette and Jaganathan, Srikrishna and Strobel, Norbert and Egger, Bernhard and Kowarschik, Markus and Maier, Andreas}, title = {BOSS: Bones, organs and skin shape model}, series = {Computers in Biology and Medicine}, volume = {165}, journal = {Computers in Biology and Medicine}, issn = {0010-4825}, language = {en} } @article{GustavsenRahimpour, author = {Gustavsen, B. and Rahimpour, Ebrahim}, title = {High-Frequency Transformer and Reactor Models for Network Studies, Part C: Grey Box Models}, series = {Conseil International des Grands R{\´e}seaux {\´E}lectriques (CIGRE) TB 902}, journal = {Conseil International des Grands R{\´e}seaux {\´E}lectriques (CIGRE) TB 902}, isbn = {978-2-8587-3607-2}, pages = {1 -- 102}, language = {en} } @article{AdamyVoutsasWillert, author = {Adamy, J{\"u}rgen and Voutsas, Kyriakos and Willert, Volker}, title = {Ein binaurales Richtungsh{\"o}rsystem f{\"u}r mobile Roboter in echoarmer Umgebung}, series = {at - Automatisierungstechnik}, volume = {51}, journal = {at - Automatisierungstechnik}, number = {9}, publisher = {Walter de Gruyter GmbH}, issn = {2196-677X}, doi = {10.1524/auto.51.9.387.22718}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:863-opus-60022}, pages = {387 -- 395}, abstract = {In diesem Beitrag wird ein binaurales Lokalisationsmodell f{\"u}r einen autonomen mobilen Roboter vorgestellt, das sich am menschlichen H{\"o}rsystem orientiert. Im Mittelpunkt steht die technische Umsetzung der neuronalen Verarbeitungsmechanismen der Olivenkerne des auditorischen Systems, die ein binaurales Richtungsh{\"o}ren erm{\"o}glichen. Das System ist in der Lage, im Bereich des Sichtfeldes des Roboters eine Schallquelle in echoarmer, d.h. reflexionsarmer Umgebung anhand von Laufzeitunterschieden und Pegeldifferenzen zu lokalisieren. Die M{\"o}glichkeit des Richtungsh{\"o}rens verbessert die Wahrnehmung der unmittelbaren Umgebung des Roboters entscheidend und erlaubt z.B. die Ausrichtung des Roboterkopfes zur Schallquelle.}, language = {de} } @inproceedings{HolderEberspaecherWaldschmidt, author = {Holder, Marvin and Ebersp{\"a}cher, Mark and Waldschmidt, Christian}, title = {Radar imaging device using prism shaped aperture}, series = {2024 Kleinheubach Conference}, booktitle = {2024 Kleinheubach Conference}, publisher = {IEEE}, doi = {10.23919/IEEECONF64570.2024.10738992}, pages = {1 -- 4}, language = {en} } @phdthesis{Ziegler, author = {Ziegler, Andreas}, title = {Possibilities and limitations of active battery management systems for lithium-ion batteries}, editor = {Montesinos-Miracle, Daniel and Ackva, Ansgar}, pages = {213}, abstract = {Lithium-Ion Batteries (LIBs) are being used in more and more areas of application. At the same time, their chemical composition and their designs are constantly evolving. Major developments are also taking place in the field of Battery Management Systems (BMSs), which are essential for the safe operation of LIBs. The focus is on intelligent charge redistribution between individual cells, called Active Balancing (AB). This thesis deals with the possibilities and limitations of AB. An empirical long-term experiment provides new insights into the ageing behaviour of batteries that are actively balanced during their entire service life. The main objective of this work is to to demonstrate influences on the ageing behaviour of batteries that are still unknown at present. A literature study shows that previous work in this area is often based on theoretical approaches and rarely has a functional proof through measurement results. Most significant statements from literature are examined. These include the increase in discharge capacity, energy efficiency and service life associated with AB, as well as lower parameter variation of the individual cells installed in the battery. Before starting the empirical experiment, the current state of the art is captured and a universal AB topology is selected from a large number of known systems. The operating behaviour as well as the balancing algorithms are explained in detail in order to be able to understand the influences occurring during the ageing of the batteries. The ageing experiment itself is a comparison test between commercial Passive Balancing (PB) and the novel AB. Two identical battery packs are aged under uniform conditions, but with the two different BMSs mentioned above. At the end of the ageing process, the battery packs are disassembled and the parameters of all individual cells are determined for further investigation. The main contribution of this work is the proof of effects through AB, especially with large battery loads. Both the increase in discharge capacity and the service life are demonstrated. The work shows how parameter variation of individual cells can be made visible during operation. It also presents diagnosis and calculation methods. The energetic efficiency of the batteries cannot be increased, since the self-consumption of the power electronics of the AB system is always higher than with PB. However, the overall efficiency of the battery increases due to an increase in capacity and an extension of the service life. The thesis also shows that with lower battery loads, the use of AB is not beneficial any more or may lead to negative effects. In such applications conventional PB is sufficient. The results obtained during pack ageing are additionally substantiated and extended by the measurement results of the individual cells. At the end of the thesis, all results and contributions are summarised. Suggestions for optimisation as well as further research ideas are presented as a possible starting point for further scientific studies.}, language = {en} } @article{GenslerMalkmusOckermannetal., author = {Gensler, Marius and Malkmus, Christoph and Ockermann, Philipp and M{\"o}llmann, Marc and Hahn, Lukas and Salehi, Sahar and Luxenhofer, Robert and Boccaccini, Aldo R. and Hansmann, Jan}, title = {Perfusable Tissue Bioprinted into a 3D-Printed Tailored Bioreactor System}, series = {Bioengineering}, volume = {11}, journal = {Bioengineering}, number = {1}, publisher = {MDPI}, issn = {2306-5354}, doi = {10.3390/bioengineering11010068}, pages = {16}, abstract = {Bioprinting provides a powerful tool for regenerative medicine, as it allows tissue construction with a patient's specific geometry. However, tissue culture and maturation, commonly supported by dynamic bioreactors, are needed. We designed a workflow that creates an implant-specific bioreactor system, which is easily producible and customizable and supports cell cultivation and tissue maturation. First, a bioreactor was designed and different tissue geometries were simulated regarding shear stress and nutrient distribution to match cell culture requirements. These tissues were then directly bioprinted into the 3D-printed bioreactor. To prove the ability of cell maintenance, C2C12 cells in two bioinks were printed into the system and successfully cultured for two weeks. Next, human mesenchymal stem cells (hMSCs) were successfully differentiated toward an adipocyte lineage. As the last step of the presented strategy, we developed a prototype of an automated mobile docking station for the bioreactor. Overall, we present an open-source bioreactor system that is adaptable to a wound-specific geometry and allows cell culture and differentiation. This interdisciplinary roadmap is intended to close the gap between the lab and clinic and to integrate novel 3D-printing technologies for regenerative medicine.}, language = {en} } @article{HeinOeserZiegleretal., author = {Hein, Thiemo and Oeser, David and Ziegler, Andreas and Montesinos-Miracle, Daniel and Ackva, Ansgar}, title = {Aging Determination of Series-Connected Lithium-Ion Cells Independent of Module Design}, series = {Batteries}, volume = {9}, journal = {Batteries}, number = {3}, doi = {10.3390/batteries9030172}, abstract = {In this work, a battery consisting of eight commercial NMC/graphite cells connected in series was cycled to 60\% of its initial capacity. During the test, special care was taken to ensure that the results were not influenced by either the module assembly or the module design. For this purpose, the cells were virtually connected in a laboratory environment with the help of the test device as if they were operated together in a battery. Extrinsic influences that affect cell aging were thus reduced to a minimum. Differential Voltage Analysis (DVA), Electrochemical Impedance Spectrum (EIS), and relaxation measurements were performed to analyze the aging behavior of each cell. The results show that despite a theoretically perfect module design, Cell-to-Cell Variations (CtCV) occurred during aging. The shifting Depth of Discharge (DoD) values among the cells further amplify CtCV. Lithium plating was also observed in the faster aging cells after cyclic aging, suggesting that this aging effect contributes significantly to the development of CtCV. After the aging test, the battery was equipped with an active balancing system that maximizes capacity utilization. More important, the balancing charges which are calculated iteratively within the used balancing algorithm show a strong correlation to the pure capacity losses and thus provide a new way to determine the capacity values of each cell individually without disassembling the battery.}, language = {en} } @techreport{Ackva, author = {Ackva, Ansgar}, title = {Hochdynamischer Umrichter in Hybridstruktur : Schlussbericht im F{\"o}rderprogramm FHprofUnt : Laufzeit des Vorhabens: 01.10.2012 bis 30.09.3015}, publisher = {Hochschule f{\"u}r angewandte Wissenschaften W{\"u}rzburg-Schweinfurt}, address = {Schweinfurt}, doi = {10.2314/gbv:876282885}, pages = {21}, language = {de} } @techreport{AckvaKuechler, author = {Ackva, Ansgar and K{\"u}chler, Andreas}, title = {Konvergenz elektrischer Energietechnologien : Akronym: KEE-TECH : Schlussbericht zur Erstellung des Strategiekonzepts}, publisher = {Hochschule f{\"u}r angewandte Wissenschaften W{\"u}rzburg-Schweinfurt}, address = {W{\"u}rzburg}, doi = {10.2314/GBV:883086484}, pages = {7}, language = {de} } @techreport{Ackva, author = {Ackva, Ansgar}, title = {Vorhabenbezeichnung: Bat-PA-40 : Schlussbericht : Berichtszeitraum: 01.02.2018 bis 31.01.2019}, publisher = {Hochschule f{\"u}r Angewandte Wissenschaften W{\"u}rzburg-Schweinfurt}, doi = {10.2314/kxp:1681868938}, language = {de} } @techreport{Ackva, author = {Ackva, Ansgar}, title = {Multilevel-Umrichter Pr{\"u}fsystem : Schlussbericht : Berichtszeitraum: 01.09.2014-31.08.2015}, publisher = {Hochschule f{\"u}r angewandte Wissenschaften W{\"u}rzburg-Schweinfurt}, address = {Schweinfurt}, doi = {10.2314/gbv:872408639}, pages = {30}, language = {de} } @article{HolderEberspaecherWaldschmidt, author = {Holder, Marvin and Ebersp{\"a}cher, Mark and Waldschmidt, Christian}, title = {A hybrid algorithm to process millimeter wave images with prism-shaped aperture}, series = {Advances in Radio Science}, volume = {25}, journal = {Advances in Radio Science}, number = {23}, publisher = {Copernicus GmbH}, issn = {1684-9973}, doi = {10.5194/ars-23-101-2025}, pages = {101 -- 111}, abstract = {To process images of a prism-shaped aperture in a radar imaging context, a hybrid algorithm is derived. This hybrid algorithm combines the benefits of backprojection and the Omega-K algorithm in terms of computational performance and flexibility. As a demonstration for an application of this algorithm, a 3D inspection system based on millimeter wave imaging is introduced. The system scans through the object, while it is passing on a conveyor belt. It comprises a curved antenna layout, which is able to synthesize the prism-shaped aperture. This aperture is shown to have superior resolution capabilities compared to a planar aperture. Some potential pitfalls when implementing the hybrid algorithm are assessed. Approximation formulae to estimate the achievable resolution are derived. The introduced algorithm is analyzed regarding its point spread function and compared to backprojection with the help of numerical simulations to demonstrate its potential.}, language = {en} } @article{YuekselenRahimpour, author = {Y{\"u}kselen, Emir and Rahimpour, Ebrahim}, title = {An improvement in the design process of sustainable peak power rating transformer for solar utility}, series = {International Journal of Electrical Power \& Energy Systems}, volume = {170}, journal = {International Journal of Electrical Power \& Energy Systems}, publisher = {Elsevier BV}, issn = {0142-0615}, doi = {https://doi.org/10.1016/j.ijepes.2025.110928}, pages = {1 -- 13}, abstract = {The transformer industry faces critical challenges, such as maintaining reliable production while meeting rising sustainability requirements. This paper introduces a significant advancement in the design and optimization of a transformer dedicated to a photovoltaic power plant, which exhibits a unique loading cycle distinct from standard power and distribution transformers. The main aim is to minimize the carbon footprint by enhancing the design process to improve operational performance, efficiency, and functional reliability. Such upgrades are essential for transitioning to a zero-emission electricity system and developing green energy projects. In this paper, a transformer has been studied using a combination of electrical design and 3D finite element method simulation to evaluate various design parameters. An optimization study has been conducted using an innovative multi-objective genetic algorithm utilizing a cost function that factors in size and material costs to identify the most efficient and cost-effective design solutions. The proposed design method was then validated through thermal model simulations and experimental tests based on the photovoltaic load cycle. A comparison of critical thermal parameters directly affecting the transformer's lifetime and reliability was also drawn. The results were consistent with the expected outcomes, confirming the effectiveness and reliability of the proposed design methodology.}, language = {en} } @inproceedings{YuekselenRahimpour, author = {Y{\"u}kselen, Emir and Rahimpour, Ebrahim}, title = {An Optimization Approach for Sustainable Transformer Design in Photovoltaic Power Plants", 4th IEEE International Conference on Power Electronics Smart Grid and Renewable Energy}, series = {4th IEEE International Conference on Power Electronics Smart Grid and Renewable Energy}, booktitle = {4th IEEE International Conference on Power Electronics Smart Grid and Renewable Energy}, language = {en} } @inproceedings{MeuserRahimpour, author = {Meuser, Martin and Rahimpour, Ebrahim}, title = {Analyzing of Non-Standard Overvoltages in Different Types of Power Transformer Windings Using Frequency Domain and Time Domain Severity Factors}, series = {CIGRE SC A2 \& D1 Joint Colloquium}, booktitle = {CIGRE SC A2 \& D1 Joint Colloquium}, language = {en} } @inproceedings{RahimpourPortilloDragostinov, author = {Rahimpour, Ebrahim and Portillo, A. and Dragostinov, S.}, title = {Testing Challenges in Impulse Testing of Transformers}, series = {CIGRE SC A2 \& D1 Joint Colloquium}, booktitle = {CIGRE SC A2 \& D1 Joint Colloquium}, language = {en} } @inproceedings{AbouhosseiniDarziRahimpourMirzaieetal., author = {Abouhosseini-Darzi, Mohammad and Rahimpour, Ebrahim and Mirzaie, Mohammad and Shayegani Akmal, Amir Abbas}, title = {Investigating the Effects of Moisture Distribution on the Electric Field and Leakage Current of Power Transformer Bushings}, series = {IEEE Electrical Insulation Conference (EIC)}, booktitle = {IEEE Electrical Insulation Conference (EIC)}, publisher = {IEEE}, isbn = {979-8-3315-2608-5}, issn = {2993-3684}, doi = {10.1109/EIC63069.2025.11123376}, abstract = {Bushings are one of the most important and essential equipment of power transformers. Statistics show that one of the main causes of transformer failures is due to bushing problems. One of the main reasons for bushing failures is the penetration of moisture into its internal insulation system. The moisture affects the dielectric properties and leads to an increase in its leakage current. These effects lead to changes in the electric field of the inner insulating layers of the bushings, so it is necessary to investigate these effects. In this paper, the changes of the electric field in the insulating layers of a sample bushing have been investigated with considering the different moisture distribution between the layers. This evaluation has been done during the moisture diffusion time, from the start of penetration to the time of uniformity of moisture in all layers. Also, the moisture effects on the bushing leakage current under above conditions have been studied. For this purpose, an OIP bushing is modeled in COMSOL Multiphysics software and the simulations are carried out based on Finite Element Method (FEM) and finally the obtained results are analyzed. The results show that the moisture distribution in the bushing can have an important effect on the internal electric fields. Also, according to the results, the moisture distribution inside the bushing does not have a great effect on the leakage current and this current is only affected by the volume of the moisture penetrated inside the bushing.}, language = {en} } @article{AbouhosseiniDarziMirzaieShayeganiAkmaletal., author = {Abouhosseini-Darzi, Mohammad and Mirzaie, Mohammad and Shayegani Akmal, Amir Abbas and Rahimpour, Ebrahim}, title = {Calculation and Analysis of the Electric Field of the OIP Bushings under Internal Humidity and Surface Polluted Conditions using FEM}, series = {Iranian Journal of Electrical and Electronic Engineering}, volume = {21}, journal = {Iranian Journal of Electrical and Electronic Engineering}, number = {3}, doi = {10.22068/IJEEE.21.3.3360}, pages = {1 -- 11}, abstract = {Bushings are one of the most important components of electrical equipment such as power transformers, reactors, capacitors. Most of the installed bushings have Oil-Immersed Paper (OIP) insulation structure. Bushing failure is caused by various reasons such as poor manufacturing process, overloading and also poor installation process, but moisture ingress is one of the main reasons of OIP bushing defect during its operation. In this paper, the electric field distribution of OIP bushings in multiple situations are simulated and effects of moisture distribution are analyzed. The simulations are stablished in polluted and clean surfaces of the studied bushing and done by COMSOL Multiphysics Software. The results show that non-uniform moisture distribution has a significant effect on electric fields of OIP insulation. This effect strongly increases with increasing the pollution on the external insulator of the bushing. © 2025, Iran University of Science and Technology. All rights reserved.}, language = {en} } @inproceedings{AlAbadiRahimpourGamil, author = {Al-Abadi, A. and Rahimpour, Ebrahim and Gamil, Ahmed}, title = {Dynamisches thermisches Verhalten von mit Ester-Fl{\"u}ssigkeit gef{\"u}llten Transformatoren f{\"u}r Offshore-Windkraftanwendungen in kalten Klimazonen}, series = {18th Transformer-Life-Management Konferenz}, booktitle = {18th Transformer-Life-Management Konferenz}, language = {de} } @inproceedings{RahimpourGhorbalMirzaei, author = {Rahimpour, Ebrahim and Ghorbal, Mohammed Bilal and Mirzaei, Hassan Reza}, title = {Application of the Nonlinear Kernel Principal Component Analysis in Detecting Disk-to-Disk Faults along a Transformer Winding}, series = {3rd International Conference - Tesla Innovation Days}, booktitle = {3rd International Conference - Tesla Innovation Days}, language = {en} } @inproceedings{GhorbalMirzaeiRahimpour, author = {Ghorbal, Mohammed Bilal and Mirzaei, Hassan Reza and Rahimpour, Ebrahim}, title = {Detection of Disk Space Variation in Power Transformers using Nonlinear Dimensionality Reduction Algorithm}, series = {24th International Symposium on High Voltage Engineering}, booktitle = {24th International Symposium on High Voltage Engineering}, language = {en} } @inproceedings{MeuserRahimpourEslamian, author = {Meuser, Martin and Rahimpour, Ebrahim and Eslamian, Morteza}, title = {An Inductance Matrix Expansion Method for Transient Analysis of Power Transformer using Single Turn Model}, series = {24th International Symposium on High Voltage Engineering}, booktitle = {24th International Symposium on High Voltage Engineering}, language = {en} } @inproceedings{MeuserRahimpourEslamian, author = {Meuser, Martin and Rahimpour, Ebrahim and Eslamian, Morteza}, title = {Induktivit{\"a}tsmatrixerweiterung f{\"u}r die Transientenanalyse in Leistungstransformatoren}, series = {18th Transformer-Life-Management Konferenz}, booktitle = {18th Transformer-Life-Management Konferenz}, language = {de} } @article{GustavsenRahimpour, author = {Gustavsen, B. and Rahimpour, Ebrahim}, title = {High-Frequency Transformer and Reactor Models for Network Studies}, series = {Electra}, journal = {Electra}, number = {328}, pages = {1 -- 13}, language = {en} }