@article{Himmelstoss, author = {Himmelstoss, Felix}, title = {Quasi Resonant Zero Current Switching Modified Boost Converter (QRZCSMBC)}, series = {WSEAS Transactions on Power Systems}, volume = {Volume 22}, journal = {WSEAS Transactions on Power Systems}, doi = {10.37394/23201.2023.22.8}, pages = {55 -- 62}, subject = {DC/DC converter}, language = {en} } @article{Himmelstoss, author = {Himmelstoss, Felix}, title = {Third order converters with current output for driving LEDs}, series = {WSEAS Transactions on Power Systems}, volume = {Volume 17}, journal = {WSEAS Transactions on Power Systems}, doi = {10.37394/232016.2022.17.40}, pages = {402 -- 409}, subject = {DC/DC converters}, language = {en} } @inproceedings{VeiglKlausAigneretal., author = {Veigl, Christoph and Klaus, Benjamin and Aigner, Benjamin and Wagner, Manuel}, title = {Universal Access Panel: A Novel Approach for Accessible Smart Homes and IoT}, series = {Computers Helping People with Special Needs / Proceedings of the 18th International Conference ICCHP-AAATE 2022, July 11-15, 2022, Lecco, Italy}, booktitle = {Computers Helping People with Special Needs / Proceedings of the 18th International Conference ICCHP-AAATE 2022, July 11-15, 2022, Lecco, Italy}, doi = {https://doi.org/10.1007/978-3-031-08645-8_18}, pages = {148 -- 158}, abstract = {Although various standards and guidelines for accessible design exist, many modern digital devices lack even basic accessibility features. In particular, touchscreens without haptic feedback and a highly complex menu navigation impose serious hurdles for many people - especially for people with disabilities and elderly persons. In this work, we present the Universal Access Panel (UAP) for enabling barrier-free access to home appliances and IoT devices. The system offers a novel, radically simple, multimodal user interface consisting of just a few interaction elements for accessing dedicated functions of the connected home. Using established APIs and communication protocols such as HomeConnect or OpenHab, various domestic appliances, consumer products and smart home devices can be controlled from a single, multimodal interaction console. The system has been designed in cooperation with visually impaired accessibility experts and a user study was conducted with people from the target group. The results show a high overall usability of the prototype.}, subject = {Home Appliances}, language = {en} } @inproceedings{HimmelstossWindisch, author = {Himmelstoss, Felix and Windisch, Michael}, title = {A capacitor-free driving stage for light emitting diodes}, series = {21th International Conference on Renewable Energies and Power Quality (ICREPQ'23) Madrid (Spain), 24th to 26th May 2023}, volume = {Vol. 21}, booktitle = {21th International Conference on Renewable Energies and Power Quality (ICREPQ'23) Madrid (Spain), 24th to 26th May 2023}, doi = {10.24084/repqj21.278}, pages = {220 -- 225}, abstract = {Electrolytic capacitors have the disadvantage of pronounced aging. Non-electrolytic capacitors are therefore used in applications where long-life is important. In this paper we present a driving stage for LEDs without any capacitive elements. The basic topology is a Buck converter with one coil, one active, and one passive switch. Instead of the output capacitor, series connections of one or more LEDs and an active switch are connected. An additional diode is connected between the output and the input to achieve a current path, when all LED- paths are off. A nonlinear hysteresis controller is used to achieve a robust control. A system with three switchable LED-strings is analyzed. Design hints are given and the function is proved with the help of LTSpice simulations. The system can be used for lighting purposes with the possibility to change the chrominance. The potentiality to transmit data is also treated.}, subject = {DC-to-DC converter}, language = {en} } @inproceedings{HimmelstossWindisch, author = {Himmelstoss, Felix and Windisch, Michael}, title = {Tapped inductor Boost with exploitation of the stray energy}, series = {Proceedings of 2022 IEEE 20th International Power Electronics and Motion Control Conference (PEMC 2022), Brasov, Rumania, Sep. 25-29}, booktitle = {Proceedings of 2022 IEEE 20th International Power Electronics and Motion Control Conference (PEMC 2022), Brasov, Rumania, Sep. 25-29}, doi = {10.1109/PEMC51159.2022.9962849}, pages = {75 -- 80}, abstract = {Tapped inductor DC-to-DC converters are interesting circuits, the winding ratio of the two windings mounted on the same core change the voltage transformation ratio compared to the untapped inductor. The tapped inductor converters are especially useful, when high or low voltage transformation ratios have to be realized. The disadvantage of this concept is that the coupling between the two windings is not total and can be described by the stray or leakage inductance. This stray inductance leads to a high overvoltage at the active switch, and therefore also across other elements of the converter. After a short summery of the ideal tapped Boost converter, the design of an RCD snubber which limits the overvoltage is explained. To improve the efficiency of the converter two active snubber networks are treated, which feed the energy stored in the snubber capacitor into the input source or into the output circuit. Simulations are used to prove these considerations.}, subject = {DC/DC converter}, language = {en} } @inproceedings{HimmelstossVotzi, author = {Himmelstoss, Felix and Votzi, Helmut}, title = {Two-Stage Step-up Converter with Different Voltage Transformation Ratios depending on the Duty Cycle}, series = {20th International Conference on Renewable Energies and Power Quality (ICREPQ'22) Vigo (Spain), 27th to 29th July 2022}, volume = {Vol. 20}, booktitle = {20th International Conference on Renewable Energies and Power Quality (ICREPQ'22) Vigo (Spain), 27th to 29th July 2022}, doi = {10.24084/repqj20.218}, pages = {66}, abstract = {A two-stage converter with high output voltage ratio and reduced current stress of the inductors and partly reduced voltage stress is discussed. The function is explained with the help of voltage and current diagrams. The voltage transformation ratio changes between a quadratic step-up for duty cycles lower 0.5 and a double Boost converter for duty cycles higher than 0.5. Dimensioning hints, the control law for feed-forward controls, the transient when the supply is turned on is discussed and some simulations are given. A comparison to other two-stage converters is also treated.}, subject = {Quadratic boost}, language = {en} } @inproceedings{FibichHorauerObermaisser, author = {Fibich, Christian and Horauer, Martin and Obermaisser, Roman}, title = {Bitstream-Level Interconnect Fault Characterization for SRAM-based FPGAs}, series = {Proceedings of the 2023 Design, Automation \& Test in Europe Conference \& Exhibition (DATE 2023), pp. 1-2, 16-18 April 2023, Antwerp, Belgium}, booktitle = {Proceedings of the 2023 Design, Automation \& Test in Europe Conference \& Exhibition (DATE 2023), pp. 1-2, 16-18 April 2023, Antwerp, Belgium}, doi = {10.23919/DATE56975.2023.10136911}, pages = {2}, subject = {FPGA}, language = {en} } @inproceedings{SteinerLuegerWallischetal., author = {Steiner, Fabian and Lueger, Bernhard and Wallisch, Bernhard and Polzer, Thomas}, title = {Automated Evaluation System for Microcontroller Assignments}, series = {2023 IEEE Global Engineering Education Conference (EDUCON), Kuwait}, booktitle = {2023 IEEE Global Engineering Education Conference (EDUCON), Kuwait}, organization = {IEEE}, isbn = {979-8-3503-9943-1}, issn = {2165-9567}, doi = {https://doi.org/10.1109/EDUCON54358.2023.10125112}, pages = {7}, abstract = {As IoT systems have increased the number of deployed embedded devices drastically and most of these devices are used in safety or security critical environments, the education of embedded software engineers is more important than ever. A critical part of their education is the development of their intuition for secure and safe software. In this paper 1 1 This research was funded by the city of Vienna (MA-23 call 21, project no. 9). we present an evaluation system used to generate fast and accurate feedback for student submission in, but not limited to, embedded software development courses. The system can be used as a first feedback loop to outline to the students where problems exist in their code and give them the opportunity to analyze and correct their errors. These extra steps ensure that the students can and will be notified early about their mistakes and can search for correct solutions, supporting the student's learning process. We present the implementation of the system and analyze its deployment in a microcontroller software development lecture. This analysis was done by means of surveys of the students and lecturers as well as a statistical analysis of the student submissions. The results show that the students made use of this extra features and even would prefer to have this feedback in other software development lectures as well.}, subject = {Student-Centered Learning Environments}, language = {en} } @inproceedings{HimmelstossHofschweigerVotzi, author = {Himmelstoss, Felix and Hofschweiger, Andreas and Votzi, Helmut}, title = {Quadratic Combined Forward-Flyback Converter}, series = {Power Conversion and Intelligent Motion Conference (PCIM) 2023, May 9-11, 2023 Nurenberg, Germany}, booktitle = {Power Conversion and Intelligent Motion Conference (PCIM) 2023, May 9-11, 2023 Nurenberg, Germany}, doi = {10.30420/566091315}, pages = {1446 -- 1453}, subject = {DC/DC converter}, language = {en} } @inproceedings{Himmelstoss, author = {Himmelstoss, Felix}, title = {Cascaded control of a Buck converter designed and simulated with the help of LTSpice}, series = {6th International European Congress on Interdisciplinary Scientific Research, Aug. 26-27, 2022, Bukarest, Rumania}, booktitle = {6th International European Congress on Interdisciplinary Scientific Research, Aug. 26-27, 2022, Bukarest, Rumania}, pages = {1086 -- 1096}, subject = {education}, language = {en} }