TY - CHAP A1 - Stock, Alexander A1 - Teigelkötter, Johannes A1 - Staudt, Stefan A1 - Büdel, Johannes T1 - Highly Dynamic Calculation of Power Quantities and Further Analysis of Inverter-Fed Machines T2 - 2018 20th European Conference on Power Electronics and Applications (EPE'18 ECCE Europe) N2 - In this contribution, a highly dynamic calculation method of power quantities and additional electrical quantities, such as RMS values and fundamental waveforms, is presented. Typically, these quantities are calculated periodically based on the fundamental cycle of the electrical voltages and currents. Hence, they are well defined during steady state conditions for ideal periodical waveforms. During dynamic balancing processes, electrical signals are non-periodic. In a strict sense, the fundamental cycle-based definitions, which are well known from the literature, are not valid for these transient signals. However, this paper presents a novel definition for the calculation of cycle-based quantities based on the switching cycle of the inverter output voltages. This definition delivers instantaneous results during transient balancing processes, whereby it approximates the conventional fundamental cycle-based definitions during the steady state. KW - Elektrische Maschine KW - Umrichter Y1 - 2018 UR - https://ieeexplore.ieee.org/document/8515600 SN - 978-1-5386-4145-3 ER - TY - CHAP A1 - Büdel, Johannes A1 - Teigelkötter, Johannes A1 - Stock, Alexander T1 - Optimized Dual Two-Level Inverter for Safe and Reliable Operation of Machines with Superconductive Stator Windings T2 - 2019 21st European Conference on Power Electronics and Applications (EPE '19 ECCE Europe) N2 - This paper aims to present an optimized inverter topology, based on the dual two-level inverter, for feeding an open-end winding electrical machine with superconductive stator windings and a superconductive rotor. In order to achieve a high torque density, the stator windings are built of several superconducting tapes being in parallel. One inverter of the dual two-level inverter is equipped with powerful IGBT semiconductors and supplies the machine with energy. The second inverter is a low voltage MOSFET inverter that monitors the superconductor resistance (quench detection) and balances the current on the parallel superconductive tapes for guaranteeing an optimum operation with respect to the superconductive losses. KW - Elektrische Maschine KW - Wechselrichter Y1 - 2019 UR - https://ieeexplore.ieee.org/document/8915524 SN - 978-1-7281-2361-5 U6 - https://doi.org/10.23919/EPE.2019.8915524 ER - TY - CHAP A1 - Büdel, Johannes A1 - Teigelkötter, Johannes A1 - Stock, Alexander A1 - Herkommer, Christian A1 - Kuhlmann, Kai T1 - High Dynamic Power Balancing for Dual Two-Level Inverters during High-Speed Machine Operation T2 - 2020 22nd European Conference on Power Electronics and Applications (EPE'20 ECCE Europe) N2 - This paper aims to present optimized square-wave modulation strategies for the dual two-level inverter, fed by two separate and galvanically isolated energy sources, to balance and control the energy distribution of both inverter systems. Especially for high-speed operation, the methods keep the machine in the required state while decreasing the switching operations to a minimum. Method one aims to compensate voltage fluctuations of variable DC-link voltages, while the second method ensures a symmetrical power distribution for the two inverter systems. In addition, both methods offer the possibility of adapting the amplitude of the usually fixed fundamental load voltage during square-wave modulation. KW - Wechselrichter Y1 - 2020 UR - https://ieeexplore.ieee.org/document/9215695 SN - 978-1-7281-9807-1 U6 - https://doi.org/10.23919/EPE20ECCEEurope43536.2020.9215695 ER - TY - CHAP A1 - Büdel, Johannes A1 - Teigelkötter, Johannes A1 - Stock, Alexander A1 - Kuhlmann, Kai A1 - Lang, Klaus A1 - Ott, Patrick T1 - Testing of High-Power Traction Batteries T2 - SMSI 2021 - System of Units and Metreological Infrastructure N2 - Electric drives in road vehicles with a battery as energy storage are about to be introduced to the mass market. In order to guarantee the quality and operational safety of battery-powered vehicles, considerable efforts must be made by car manufacturers and their suppliers. Since the properties of the batteries significantly determine the performance of the vehicles, special test benches with precise measuring systems are required for the accurate determination of the battery properties. The safety devices of the traction batteries must also be tested on high-performance test benches. In this paper the necessary test benches and the corresponding measuring systems are presented. Estimations of the measurement uncertainty and possibilities to increase measurement accuracy are presented. KW - Traktionsbatterie KW - Elektrofahrzeug Y1 - 2021 UR - https://www.ama-science.org/proceedings/details/4061 SN - 978-3-9819376-4-0 U6 - https://doi.org/10.5162/SMSI2021/C7. SP - 294 EP - 295 ER - TY - JOUR A1 - Büdel, Johannes A1 - Teigelkötter, Johannes ED - Schäfer, Heinz T1 - Doppelzweipunktwechselrichter für Elektrofahrzeuge - Systemeigenschaften und Steuerung JF - Elektrische Antriebstechnologie für Hybrid- und Elektrofahrzeuge N2 - Im vorliegenden Beitrag wird die Topologie des Doppelzweipunktwechselrichters für die Anwendung in Elektrofahrzeugen vorgestellt. Dazu werden zunächst der Schaltungsaufbau und die spezifischen Schaltungseigenschaften näher erläutert. Anschließend werden relevante Vorteile dieser Topologie für die Anwendung in Elektrofahrzeugen dargestellt. Für die Kombination unterschiedlicher Energiequellen mit Hilfe des Doppelzweipunktwechselrichters werden geeignete Steuerungsstrategien präsentiert und anhand von realen Messungen am Systemprüfstand verifiziert. Mit dem Vorgestellten Verfahren kann die Leistungsaufteilung auf die beiden Energiespeicher und deren Energieaustausch untereinander mit hohem Freiheitsgrad gesteuert werden. KW - Elektrofahrzeug KW - Wechselrichter Y1 - 2019 VL - 2019 IS - 149 SP - 114 EP - 127 ER - TY - CHAP A1 - Schwarzer, Christian A1 - Chew, Ly May A1 - Schnepf, Michael A1 - Stoll, Thomas A1 - Franke, Jörg A1 - Kaloudis, Michael T1 - INVESTIGATION OF COPPER SINTER MATERIAL FOR DIE ATTACH T2 - SMTA International Conference Proceedings KW - Leistungshalbleiter KW - Leistungselektronik KW - Kupfer KW - Sintern Y1 - 2018 VL - 2018 IS - Proceedings SMTAI 2018 CY - Rosemont ER - TY - CHAP A1 - Hensel, Alexander A1 - Schwarzer, Christian A1 - Scheetz, Matthias A1 - Kaloudis, Michael A1 - Franke, Jörg T1 - Investigations of Silver Sintered Interconnections 3-Dimensional Ceramics with Plasma Based Additive Copper Metallizations T2 - 2018 IEEE 20th Electronics Packaging Technology Conference (EPTC) KW - Leistungselektronik KW - Hochtemperatur KW - Sintern Y1 - 2018 U6 - https://doi.org/10.1109/EPTC.2018.8654421 VL - 2018 SP - 416 EP - 421 CY - Singapore ER - TY - CHAP A1 - Schmitt, Wolfgang A1 - Schnepf, Michael A1 - Franke, Jörg A1 - Kaloudis, Michael T1 - Investigation of a Sintering Process for Micro-Scale Copper Material T2 - 2019 SMTA Electronic in Harsh Environments Conference KW - Kupfer KW - Sintern Y1 - 2019 VL - 2019 ER - TY - CHAP A1 - Stenzel, David A1 - Schwarzer, Christian A1 - Schnepf, Michael A1 - Schmitt, Wolfgang A1 - Blank, Thomas A1 - Franke, Jörg A1 - Kaloudis, Michael T1 - Characterization of Alternative Sinter Materials for Power Electronics T2 - 22nd Microelectronics and Packaging Conference (EMPC) & Exhibition, 16 Sep 2019 - 19 Sep 2019, Conference Center PISA, Italy KW - Sintern, Silber, Kupfer KW - Leistungselektronik KW - Sintern Y1 - 2019 ER - TY - JOUR A1 - Döhring, Thorsten A1 - Pribulla, Theodor A1 - Komzik, Richard A1 - Mann, Michael A1 - Sivanic, Peter A1 - Stollenwerk, Manfred T1 - Slovak-Bavarian collaboration on the development of telescope instrumentation JF - Contributions of the Astronomical Observatory Skalnate Pleso N2 - Within the project SLOBATCO (Slovak-Bavarian Telescope Collaboration) the Astronomical Institute of the Slovak Academy of Sciences and Aschaffenburg University of Applied Sciences collaborate in the development and commissioning of scientific instrumentation for the new Ø1.3 m astronomical telescope at the Skalnaté Pleso observatory. The joint project is funded by the Bavarian Academic Center for Central, Eastern and Southeastern Europe (BAYHOST). Planned technical work packages are targeting the filter wheel software for the VIS camera, additional IR filters, and an upgrade of the mirror coating facility by additional sputtering equipment. KW - telescope KW - instrumentation KW - filter KW - camera KW - coating KW - Spiegelteleskop Y1 - 2019 UR - https://www.ta3.sk/caosp/Eedition/FullTexts/vol49no2/pp154-158.pdf VL - 2019 IS - 49 / 2 SP - 154 EP - 158 ER - TY - GEN A1 - Mann, Michael A1 - Döhring, Thorsten A1 - Pribulla, Theodor A1 - Komzik, Richard A1 - Sivanic, Peter A1 - Stollenwerk, Manfred ED - Skopal, Augustin T1 - Power quality evaluation for observatories N2 - Within the project SLOBATCO the question did arise, to what extend observatories have to rely on adequate power quality, e.g. the perfect sinusoidal shape of supply voltage and current, in order to ensure safe operation and accurate measurement results. International power quality standards are put in perspective with requirement specifications. Telescope operators indicate partial or total loss of function of measurement instruments. Measurements conducted during SLOBATCO project substantiate the need for power quality measurement campaigns. N2 - Poster KW - instrumentation KW - site testing KW - telescope KW - Sternwarte KW - Elektrizitätsversorgung Y1 - 2019 ER - TY - JOUR A1 - Mann, Michael A1 - Pribulla, Theodor A1 - Döhring, Thorsten A1 - Komzik, Richard A1 - Sivanic, Peter T1 - Power quality—Evaluation of safe operation of observatories JF - Astronomische Nachrichten N2 - The electric power supply of astronomical observatories has to manage a conflict of interest: Observatories are situated at remote locations, they have a high consumption of electric power while measuring electric signals as sensitively as possible. Within the project SLOBATCO, the question did arise, to what extent observatories have to rely on adequate power quality, for example, the perfectly sinusoidal shape of supply voltage and current, to ensure safe operation and accurate measurement results. International power quality standards are put in perspective with requirement specifications for observatories. This contribution describes themotivation, the underlying mechanisms that lead to issues, comments on the challenge in power systems engineering, proposes the instrumentation and installation, and interprets the first results. Experimental results clearly motivate the need for further measurement campaigns, as power-quality-related problems are common. A summary is provided together with an outlook and a motivation for future measurement campaigns. KW - power quality KW - observatory KW - standards KW - Sternwarte KW - Elektrizitätsversorgung KW - DEAL-Finanzierung Wiley Y1 - 2019 U6 - https://doi.org/10.1002/asna.201913672 VL - 2019 IS - 340 SP - 658 EP - 665 ER - TY - CHAP A1 - Hensel, Alexander A1 - Roth, Frederick A1 - Merz, Corinna A1 - Franke, Jörg A1 - Kaloudis, Michael T1 - Investigation of Pressureless Sintered Interconnections on Plasma Based Additive Copper Metallization for 3-Dimentional Ceramic Substrates in High Temperature Applications T2 - 22nd Microelectronics and Packaging Conference (EMPC) & Exhibition, 16 Sep 2019 - 19 Sep 2019, Conference Center PISA, Italy KW - 3D, KW - Kupfer KW - Sintern KW - Silbersintern KW - Sintern KW - Hochtemperatur Y1 - 2019 ER - TY - BOOK A1 - Borgeest, Kai T1 - Messtechnik und Prüfstände für Verbrennungsmotoren KW - Verbrennungsmotor KW - Prüfstand KW - Messtechnik KW - Kraftfahrzeugtechnik KW - Thermodynamik KW - Regelungstechnik Y1 - 2020 SN - 0000-0003-4289-0083 U6 - https://doi.org/10.1007/978-3-658-29105-1 VL - 2020 PB - Springer-Vieweg CY - Wiesbaden ET - 2. Auflage ER - TY - JOUR A1 - Kefer, Stefan A1 - Sauer, Theresia A1 - Hessler, Steffen A1 - Kaloudis, Michael A1 - Hellmann, Ralf T1 - Microstructure-Based Fiber-to-Chip Coupling of Polymer Planar Bragg Gratings for Harsh Environment Applications JF - Sensors (Basel) N2 - This article proposes and demonstrates a robust microstructure-based fiber-to-chip coupling scheme for planar Bragg grating devices. A polymer planar Bragg grating substrate is manufactured and microstructured by means of a micromilling process, while the respective photonic structures are generated by employing a sophisticated single-writing UV-exposure method. A stripped standard single mode fiber is inserted into the microstructure, which is filled with a UV-curable adhesive, and aligned with the integrated waveguide. After curing, final sensor assembly and thermal treatment, the proposed coupling scheme is capable of withstanding pressures up to 10 bar, at room temperature, and pressures up to 7.5 bar at an elevated temperature of 120 °C. Additionally, the coupling scheme is exceedingly robust towards tensile forces, limited only by the tensile strength of the employed single mode fiber. Due to its outstanding robustness, the coupling scheme enables the application of planar Bragg grating devices in harsh environments. This fact is underlined by integrating a microstructure-coupled photonic device into the center of a commercial-grade carbon fiber-reinforced polymer specimen. After its integration, the polymer-based Bragg grating sensor still exhibits a reflection peak with a dynamic range of 24 dB, and can thus be employed for sensing purposes. KW - Bragg grating sensors KW - cyclic olefin copolymers KW - fiber-to-chip coupling KW - microstructures KW - micromilling Y1 - 2020 UR - https://www.mdpi.com/1424-8220/20/19/5452/htm U6 - https://doi.org/10.3390/s20195452 VL - 20 IS - 19 SP - 5452 EP - 5452 ER - TY - CHAP A1 - Borgeest, Kai T1 - Safe Development Environments for Radiation Tracing Robots T2 - Handbook of Research on Advanced Mechatronic Systems and Intelligent Robotics N2 - Robots can substitute for men in radioactively-contaminated areas. This is a suitable field to deploy robots for measurements, repair, or clearance, but development and test of such robots could be dangerous, because radiation sources need to be handled. To avoid these hazards in development or public demonstrations, safe alternatives to radiation samples have been sought using an already existing robot (EtaBot). One proposed solution is an optical substitution (“light follower”), the other one a fully-digital simulation of the contaminated area and the robot movement inside it using a hardware-in-the-loop simulator (HiL). KW - EtaBot KW - Mobile Robot KW - Mobiler Roboter KW - Künstliche Intelligenz Y1 - 2019 SN - 9781799801375 U6 - https://doi.org/doi.org/10.4018/978-1-7998-0137-5.ch006 SP - 126 EP - 138 PB - IGI Global CY - Hershey, PA ER - TY - BOOK A1 - Borgeest, Kai T1 - Elektronik in der Fahrzeugtechnik N2 - Das Buch vermittelt die Grundlagen, um die Besonderheiten der Elektronik und Software im Kfz nicht nur zu kennen, sondern auch zu verstehen. Zusätzlich wird an Beispielen die Komplexität realer Systeme im Fahrzeug vorgeführt und gezeigt, welche Anwendungen durch die Elektronik erst möglich werden. Das Spannungsfeld zwischen Sicherheit, Zuverlässigkeit und Komplexität prägt in Verbindung mit branchenüblichen Abläufen das Vorgehen bei der Entwicklung, das ein in diesem Bereich tätiger Ingenieur verstehen muss. KW - Kraftfahrzeugelektronik KW - Kfz-Elektronik KW - Automobilelektronik KW - Steuergerät KW - Motorsteuerung KW - Fahrzeugtechnik Y1 - 2020 SN - 978-3-658-23663-2 U6 - https://doi.org/10.1007/978-3-658-23664-9 PB - Springer Vieweg CY - Wiesbaden ER - TY - BOOK A1 - Borgeest, Kai T1 - Messtechnik und Prüfstände für Verbrennungsmotoren N2 - Dieses Buch vermittelt sowohl Studenten, als auch Planern und Betreibern in Industrie und Wissenschaft das nötige umfangreiche Wissen, um Messungen an Motorenprüfständen durchführen zu können. Messtechnik und Prüfstände für Verbrennungsmotoren helfen, Kraftstoff einzusparen, Treibhausgase und Schadstoffe zu reduzieren, mit kleineren Motoren mehr Leistung abzugeben sowie Komponenten und Betriebsstoffe zu optimieren. Mit den Motoren und der Abgasgesetzgebung entwickelt sich auch die für die Entwicklung erforderliche mechanische, thermodynamische und Abgasmesstechnik weiter. KW - Kraftfahrzeugtechnik KW - Verbrennungsmotor KW - Messtechnik KW - Regelungstechnik KW - Verbrennungsmotor KW - Abgas KW - Messtechnik KW - Motorenprüfstand KW - Thermodynamik KW - Prüfstand Y1 - 2024 UR - https://link.springer.com/book/10.1007/978-3-658-43284-3 SN - 978-3-658-43283-6 U6 - https://doi.org/10.1007/978-3-658-43284-3 VL - 2024 PB - Springer Vieweg CY - Wiesbaden ET - 3., überarbeitete und erweiterte Auflage ER - TY - CHAP A1 - Büdel, Johannes A1 - Kuhlmann, Kai A1 - Teigelkötter, Johannes T1 - Improved DC-Charging for Traction Drives with Hybrid Powered Dual Two-Level Inverter T2 - 2023 25th European Conference on Power Electronics and Applications (EPE'23 ECCE Europe) N2 - This contribution aims to present a new concept for power sharing of traction drives supplied by local DC grids such as partly or full equipped trolley wire nets. Therefore, a dual two-level inverter with two separate energy storages and an open-end winding machine is used. New control algorithms allow the charging of the energy sources whether two batteries, a combination of a battery and a fuel cell or a combination of battery and a flying capacitor is used. Within the scope of battery performance, this application is able to absorb or deliver the required power from a DC grid and still feed the electrical machine to enable a driving movement of the electric vehicle. As the presented concepts enable voltage balancing due to different battery loads and the use of only one dynamic energy storage in the charging operation, the shown application aims to achieve the high utilization of an electric vehicle powered by a (partly equipped) DC-grid. KW - Wechselrichter KW - Elektroantrieb KW - Elektrofahrzeug KW - Batteriefahrzeug Y1 - 2024 UR - https://ieeexplore.ieee.org/document/10264409 U6 - https://doi.org/10.23919/EPE23ECCEEurope58414.2023.10264409 ER - TY - CHAP A1 - Büdel, Johannes A1 - Teigelkötter, Johannes A1 - Kuhlmann, Kai T1 - Stoßstromversuche zur Qualifizierung von sicherheitsrelevanten Komponenten im Antriebsstrang eines Elektrofahrzeuges T2 - Testen und Validieren elektrischer Antriebsstränge 2023 N2 - Progress in the development of traction batteries requires high-performance test benches to qualify the safety-relevant components in the battery management system (BMS) for use in electric vehicles. Since all possible fault cases under all permissible operating conditions must be covered during qualification, only synthetic test circuits, in which a test requires only a short setup time, are used for this task. In this paper, an n-stage surge current generator for the generation of high short-circuit currents is presented. Using the example of a four-stage resonant circuit surge current converter, the advantages of this test circuit are explained and demonstrated by measurements. Furthermore, instructions for measuring the surge currents are given. KW - Elektrofahrzeug KW - Elektroantrieb Y1 - 2023 U6 - https://doi.org/doi.org/10.51202/9783181024126 ER - TY - CHAP A1 - Büdel, Johannes A1 - Herkommer, Christian A1 - Kuhlmann, Kai A1 - Teigelkötter, Johannes T1 - Advanced DC-charging Methods for Traction Drives with Dual Two-Level Inverter During Machine Operation T2 - 2021 23rd European Conference on Power Electronics and Applications (EPE'21 ECCE Europe) N2 - This paper aims to present a concept and especially developed control methods for an open-end winding traction drive, powered by a dual two-level inverter, where the two separate energy sources can be charged via a DC grid during operation and while being standstill. For achieving a high quality DC-current, the parasitic Back-EMF harmonics of the electrical machine will be compensated. The application aims to achieve high utilisation of the electric vehicle in combination with a partly equipped trolley wire net. KW - Wechselrichter KW - Elektroantrieb KW - Elektrofahrzeug Y1 - 2021 U6 - https://doi.org/10.23919/EPE21ECCEEurope50061.2021.9570611 ER - TY - JOUR A1 - Köhler, Tim A1 - Wölfel, Maximilian A1 - Ciba, Manuel A1 - Bochtler, Ulrich A1 - Thielemann, Christiane T1 - Terrestrial Trunked Radio (TETRA) exposure of neuronal in vitro networks JF - Environmental Research N2 - Terrestrial Trunked Radio (TETRA) is a worldwide common mobile communication standard, used by authorities and organizations with security tasks. Previous studies reported on health effects of TETRA, with focus on the specific pulse frequency of 17.64 Hz, which affects calcium efflux in neuronal cells. Likewise among others, it was reported that TETRA affects heart rate variability, neurophysiology and leads to headaches. In contrast, other studies conclude that TETRA does not affect calcium efflux of cells and has no effect on people's health. In the present study we examine whether TETRA short- and long-term exposure could affect the electrophysiology of neuronal in vitro networks. Experiments were performed with a carrier frequency of 395 MHz, a pulse frequency of 17.64 Hz and a differential quaternary phase-shift keying (π/4 DQPSK) modulation. Specific absorption rates (SAR) of 1.17 W/kg and 2.21 W/kg were applied. In conclusion, the present results do not indicate any effect of TETRA exposure on electrophysiology of neuronal in vitro networks, neither for short-term nor long-term exposure. This applies to the examined parameters spike rate, burst rate, burst duration and network synchrony. KW - Neuronales Netz Y1 - 2018 U6 - https://doi.org/10.1016/j.envres.2017.12.007 VL - 2018 IS - 162 SP - 1 EP - 7 ER - TY - JOUR A1 - Oster, Stefan A1 - Daus, Andreas A1 - Erbes, Christian A1 - Goldhammer, Michael A1 - Bochtler, Ulrich A1 - Thielemann, Christiane T1 - Long‐term electromagnetic exposure of developing neuronal networks: A flexible experimental setup JF - Bioelectromagnetics N2 - Neuronal networks in vitro are considered one of the most promising targets of research to assess potential electromagnetic field induced effects on neuronal functionality. A few exposure studies revealed there is currently no evidence of any adverse health effects caused by weak electromagnetic fields. Nevertheless, some published results are inconsistent. Particularly, doubts have been raised regarding possible athermal biological effects in the young brain during neuronal development. Therefore, we developed and characterized a flexible experimental setup based on a transverse electromagnetic waveguide, allowing controlled, reproducible exposure of developing neuronal networks in vitro. Measurement of S‐parameters confirmed very good performance of the Stripline in the band of 800–1000 MHz. Simulations suggested a flexible positioning of cell culture dishes throughout a large exposure area, as specific absorption rate values were quite independent of their position (361.7 ± 11.4 mW/kg) at 1 W, 900 MHz. During exposure, thermal drift inside cellular medium did not exceed 0.1 K. Embryonic rat cortical neurons were cultivated on microelectrode array chips to non‐invasively assess electrophysiological properties of electrogenic networks. Measurements were taken for several weeks, which attest to the experimental setup being a reliable system for long‐term studies on developing neuronal tissue. KW - RF exposure setup KW - mobile communication frequencies KW - SAR dosimetry KW - microelectrode array KW - electrophysiology KW - Neuronales Netz KW - Mikroelektrode KW - Array Y1 - 2016 U6 - https://doi.org/10.1002/bem.21974 VL - 2016 IS - 37 SP - 264 EP - 278 ER - TY - CHAP A1 - Daus, Andreas A1 - Oster, Stefan A1 - Erbes, Christian A1 - Goldhammer, Michael A1 - Bochtler, Ulrich A1 - Thielemann, Christiane T1 - Electromagnetic exposure of neuronal networks on microelectrode arrays T2 - U.R.S.I. Landesausschuss in der Bundesrepublik Deutschland e.V., Kleinheubacher Tagung, Miltenberg, Abstracts KW - Neuronales Netz KW - Mikroelektrode KW - Array Y1 - 2013 SP - 29 EP - 30 ER - TY - CHAP A1 - Oster, Stefan A1 - Daus, Andreas A1 - Goldhammer, Michael A1 - Bochtler, Ulrich A1 - Thielemann, Christiane T1 - A Flexible RF Exposure Setup for Long-term Electrophysiological Investigations on Biological Samples in Vitro T2 - Progress In Electromagnetics Research Symposium Abstracts, Stockholm, Schweden KW - Neuronales Netz KW - Array KW - Mikroelektrode Y1 - 2013 ER - TY - CHAP A1 - Goldhammer, Michael A1 - Daus, Andreas A1 - Thielemann, Christiane A1 - Bochtler, Ulrich T1 - Flexible measurement setup for electromagnetic exposition of biological samples T2 - BioEM 2009, Davos, Switzerland KW - Elektromagnetische Strahlung KW - Messung Y1 - 2014 ER - TY - CHAP A1 - Daus, Andreas A1 - Goldhammer, Michael A1 - Bochtler, Ulrich A1 - Thielemann, Christiane T1 - Electromagnetic exposition of neuronal networks in vitro T2 - Radiofrequency fields and health KW - Neuronales Netz Y1 - 2014 ER - TY - CHAP A1 - Daus, Andreas A1 - Goldhammer, Michael A1 - Bochtler, Ulrich A1 - Thielemann, Christiane T1 - A new approach for the investigation of long-term effects of RF radiation on cells T2 - 28th Progress In Electromagnetics Research Symposium 2010, Cambridge KW - Hochfrequenz KW - Strahlung Y1 - 2014 ER - TY - CHAP A1 - Köhler, Tim A1 - Wölfel, Maximilian A1 - Bochtler, Ulrich A1 - Thielemann, Christiane T1 - TETRA specific long-term exposure of neuronal in vitro networks T2 - BioEM2016 KW - Neuronales Netz Y1 - 2016 ER - TY - JOUR A1 - Das, Durbanjali A1 - Mahato, Bidyut A1 - Chandan, Bikramaditya A1 - Joshi, Hitesh A1 - Mahto, Kailash Kumar A1 - Das, Priyanath A1 - Fotis, Georgios A1 - Vita, Vasiliki A1 - Mann, Michael T1 - A New Cascaded Multilevel Inverter for Modular Structure and Reduced Passive Components JF - Electronics N2 - In high-power applications, achieving adequate power quality in power converter design is accomplished by utilizing multilevel inverters instead of using two-level and three-level inverters. The device generates a sinusoidal output voltage, which results in reduced total harmonic distortion and lower voltage stress on the switches and leads to lower electromagnetic interference, making it suitable for use in renewable energy applications. However, to illustrate the advantages mentioned above, a significant number of switching devices and DC sources are necessary while raising the voltage levels. This article proposes an asymmetrical voltage generation method, which operates in a ratio of 1:5 and generates 25 levels using 11 power switches. The topology is modular in structure, and each module has a lower component count, which significantly reduces the overall cost. The proposed topology is capable of generating negative output voltage levels without the use of an H-bridge configuration, where only three switches are used to generate any voltage levels. The functionality of the developed module is amended by fixing different voltage values in DC sources. This article also presents a comprehensive examination of the circuit and the functioning of various voltage levels. The advantages of the proposed inverter have been demonstrated by comparative research with the currently existing MLI topologies. Ultimately, both the simulation and experimental findings validated the practical capabilities. KW - Mehrpunktwechselrichter Y1 - 2024 U6 - https://doi.org/http://dx.doi.org/10.3390/electronics13173566 SN - 2079-9292 VL - 13 IS - 17 PB - MDPI AG ER - TY - CHAP A1 - Neumaier, Marcel A1 - Probst, Anne-Catherine A1 - Wölfel, Maximilian A1 - Bochtler, Ulrich T1 - Performance Analysis in a Digital TETRA-Simulcast System T2 - 2025 16th German Microwave Conference (GeMiC) N2 - In radio communication of mission-critical services, resilient solutions are strongly required to account for public safety. Additionally to the cellular network based on the professional mobile radio European standard TETRA, a digital TETRA-simulcast system is proposed as a redundant network to ensure area coverage in case of base station failure caused e.g. by disasters. This paper presents a preliminary study about network planning of a frequency-efficient digital TETRA-simulcast system to be physically deployed in a hilly region of Germany. Coverage as well as ray tracing analysis and channel modeling were performed by simulations and prove to be helpful tools for the systematic optimization of system performances, especially with regard to the control of intersymbol interference in overlapping zones. KW - digital radio KW - intersymbol interference KW - overlapping zones KW - quasi-synchronous transmission KW - TETRA KW - TETRA, Telekommunikation Y1 - 2025 ER - TY - BOOK A1 - Borgeest, Kai T1 - 汽车电子技术:硬件、软件、系统集成和项目管理 T2 - Automobilelektronik: Hardware, Software, Systemintegration und Projektleitung KW - Kraftfahrzeugelektronik KW - Steuergerät Y1 - 2014 SN - 978-7-111-45011-5 PB - China Machine Press ER - TY - CHAP A1 - Flachs, Dennis A1 - Bernhard, Levin A1 - Thielemann, Christiane T1 - Fully 3D-Printed Rotational Energy Harvester Based On Bipolar Charged PLA Electrets T2 - Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS) N2 - Rotational energy harvesters have emerged as a promising solution for sustainable power generation in a variety of applications, ranging from small-scale devices to large-scale industrial systems. In this work, we present a fully 3D-printed electret rotational harvester based on the biodegradable and compostable polymer polylactic acid (PLA). The 3D-printed harvester consists of a rotor made from a bipolar-charged PLA electret, electrode pairs of conductive PLA that function as the stator, and a PLA bearing. An output power of 61μ W was achieved at a rotational speed of 400 rpm and a load resistance of 28.2MΩ. To assess the durability of the harvester, particularly the 3D-printed bearing, the extent of mechanical wear was examined after one million rotations at a rotational speed of 400 rpm. The findings indicate that the rollers undergo a 1.2% loss in mass, yet the functionality remains intact. The charge decay of PLA electrets is influenced by external factors such as elevated humidity and temperature. Future research will focus on improving the charge stability of PLA by addressing these factors, expanding the potential applications of this rotational energy harvester. KW - rotational energy harvesting KW - PLA KW - electret KW - 3D printing KW - Elektret KW - 3D-Druck KW - Energy Harvesting Y1 - 2024 UR - https://ieeexplore.ieee.org/abstract/document/10814467 SN - 979-8-3503-8020-0 U6 - https://doi.org/979-8-3503-8020-0 VL - 2024 PB - IEEE ER - TY - CHAP A1 - Probst, Anne-Catherine A1 - Neumaier, Marcel A1 - Hufgard, Christopher A1 - Wölfel, Maximilian A1 - Schmitt, Christoph A1 - Bochtler, Ulrich T1 - Network Planning a Digital TETRA-Simulcast-System T2 - Kleinheubacher Tagung, Miltenberg, 23.09.2025 - 25.09.2025 KW - TETRA, Telekommunikation Y1 - 2025 ER -