Wireless power system for portable electronics

April 12, 2012 // By Nick Flaherty
Researchers in Germany have succeeded in wirelessly transmitting power from a portable transmitter module to electronics around the body.

The transmitter provides an electric current of over 100 milliwatts and has a range of about 50 centimeters. As a result, the receiver can be placed almost anywhere in the body. “The cylindrical shaped transfer module is so small and compact that it can be attached to a belt,” says Dr Holger Lausch, scientist at Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Hermsdorf.
“With our portable device, we can remotely supply power to implants, medication dosing systems and other medical applications without touching them – such as ingestible endoscopic capsules that migrate through the gastrointestinal tract and transmit images of the body‘s inside to the outside,” says Lausch.
The generator module can be traced any time – regardless of power transfer – with respect to its position and location. So if the generator is located inside a video endoscopy capsule, the images produced can be assigned to specific intestinal regions. If it is placed inside a dosing capsule, then the active ingredient in the medication can be released in a targeted manner.
In the transfer module, a rotating magnet driven by an EC motor generates a magnetic rotary field. A magnetic pellet in the receiver connects to the alternating exterior magnetic field and as a result, is set in rotation itself. The rotational movement is transformed into electricity, thus the power is produced right in the generator module.
“With magnetic coupling, power can be transported through all non-magnetic materials, such as biological tissue, bones, organs, water, plastic or even a variety of metals. Moreover, the magnetic field produced has no harmful side effects on humans. It doesn‘t even heat up tissue,” says Lausch, highlighting the advantages of the system.
Because the modules available as prototypes are scalable in terms of range, size and performance capacity, they can be used for more than medical technology applications. They can also supply power wirelessly to hermetically sealed sensors – such as