Listening to the radio is a favorite German pastime. Every day, more than 60 million people turn their radios on, especially while driving, and studies show that one in two of them are unwilling to give up enjoying radio programs behind the wheel.
Measuring the electromagnetic compatibility of vehicle components in a laboratory chamber. © Fraunhofer IZM
But in the vehicle of the future, the electric car, listening to the radio is in principle not possible, since electrical interference impedes the reception of radio waves. These disruptions are caused by the frequency converter, which changes electrical energy into mechanical energy so as to control the electric motor’s speed and direction of rotation. These converters turn the current and the voltage on and off rapidly and frequently, and the way they chop electrical energy up in fractions of a second produces electromagnetic interference. If this becomes too loud, you can only hear the electric drive, not the car radio.
To get around this problem, not only must the engine’s cabling be shielded, the motor itself must also be insulated – but this comes with a high price tag for automakers. Fortunately, researchers at the Fraunhofer Institute for Reliability and Microintegration IZM in Berlin have worked out how to significantly reduce these costs. Dr. Eckart Hoene, director of the Power Electronic Systems research group, and his team have developed a whole series of tools and methods for reducing interference. Using new simulations and calculation methods, the engineers can for instance now determine where in the vehicle components should be positioned to keep their electromagnetic interactions to a minimum.
Interference is affected by parts’ position
“The size and position of individual components – including the electric motor, the battery, the air-conditioning compressor, the charging system, the DC/DC converter and the frequency converter itself – play a crucial role. How and in what direction cables are installed is just as important, as is the thickness of their insulation,” explains Hoene. “With the help of simulations, we can also advise on the quality of the insulation and the plug connectors.”
The scientists have measurement techniques that allow them to pinpoint where exactly in the vehicle interference is coming from and to see how it spreads. What’s more, they have developed a symmetrical power module which stops interference from being emitted. This is a component of the converter and already exists as a prototype.
All German automakers have benefited from the Fraunhofer experts’ know-how. But as Hoene points out: “We advise not only German automotive manufacturers and suppliers, but increasingly Japanese and American companies, too.” Tests and fault analyses can be carried out in the institute’s own laboratory.
Electromagnetic interference is not just a problem in electric and hybrid drives. It can be a problem anywhere power electronics are installed: in avionics, or in wind and solar energy facilities, too. “Roofs with photovoltaic arrays will have a solar converter to change the direct current into alternating current, and this can impair radio reception inside of houses,” Hoene adds. Thankfully, he and his colleagues can also provide expertise and advice in these situations to help keep interference to acceptable levels.
Franz Miller | Fraunhofer Research News
Did you know that the wrapping of Easter eggs benefits from specialty light sources?
13.04.2017 | Heraeus Noblelight GmbH
To e-, or not to e-, the question for the exotic 'Si-III' phase of silicon
05.04.2017 | Carnegie Institution for Science
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
28.04.2017 | Event News
20.04.2017 | Event News
18.04.2017 | Event News
28.04.2017 | Medical Engineering
28.04.2017 | Earth Sciences
28.04.2017 | Life Sciences