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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.
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.
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.
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.
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.
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).
This contribution discusses the integration of polymer planar Bragg grating sensors (PPBG) into carbon fiber reinforced polymer (CFRP) components. For the first time, it is shown that PPBGs based on cyclic olefin copolymers can be integrated into commercial-grade composites, thereby withstanding the demanding production processes. Pre-impregnated fibers are stacked and partially modified to form a sensor pocket. Afterwards, the CFRP specimen containing the optical sensor is cured in a heated mechanical press for 2 hours at a pressure of 7 bar and a temperature of 120 °C. A subsequent evalutaion of the sensor signal shows a Bragg wavelength shift of 1236 pm and a decline in signal amplitude of -2 dB. Three-point flexural tests of the cured sample reveal a linear behavior of the sensor signal towards external loads. The determined sensitivity in dependence of the CFRP specimen's maximum central deflection is -112 pm/mm, while correlation to the applied force results in a sensitivity of -5 pm/N.