The new development allows power supply transformers to be reduced to one fifth of their current size so that the normally separate switched-mode power supply units of light-emitting diodes can be integrated into the module's heat sink.
Using a very bright arrangement of 16 Osram OSLON light-emitting diodes as an example, the ALFerMo consortium has demonstrated how a switched-mode power supply unit can be installed in cavities in the heat sink. Experts at Siemens' global Corporate Technology unit used two techniques to miniaturize the transformer. First, they quadrupled the switching frequency, because the higher the switching frequency, the smaller the transformer can be.
The researchers also developed a layered system of magnetic ceramic films. This allows the ferrite core and the windings to be easily incorporated into a ceramic circuit board. This enabled the transformer to be reduced to one fifth of its original size so that the driver circuit could be installed into an LED heat sink that is ten centimeters wide and five centimeters high. As a result, the LED module no longer requires a separate power supply unit even though it is still as bright as before.
The ALFerMo project expanded the range of possibilities for integrating circuit boards into the compact, modular power electronics assemblies of the future. Smart control systems of this type will make buildings, energy plants, and manufacturing facilities more competitive.
The researchers are now investigating the possibility of applying this technique in the most widespread types of epoxy circuit boards as well as in non-lighting systems. The ALFerMo project is part of the German Research Ministry's Power Electronics for Energy Efficiency Enhancement (LES) program. As part of its high-technology strategy, the German government provided the project with funding amounting to €2.65 million until the end of May 2013.
Dr. Norbert Aschenbrenner | Siemens InnovationNews
Producing electricity during flight
20.09.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau
Solar-to-fuel system recycles CO2 to make ethanol and ethylene
19.09.2017 | DOE/Lawrence Berkeley National Laboratory
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
22.09.2017 | Life Sciences
22.09.2017 | Medical Engineering
22.09.2017 | Physics and Astronomy