Wireless Power for Autonomous Sensor Systems
Main challenges for tomorrow's WPT technologies
Description of the magnetodynamic WPT technology.
The specificity of the magnetodynamic WPT technology is its low frequency of operation, which is typically less than 1 kHz. Low-frequency WPT technologies have the advantages of being:
Low-frequency time-varying magnetic fields dissipate very little energy in human tissues, allowing higher field amplitude than for their high-frequency counterparts. This makes low-frequency WPT suitable for safely charging wearables or biomedical implants for instance.
Moreover, low-frequency fields create very low Eddy currents and dissipate limited energy in metallic objects, contrary to high-frequency solutions. This eliminates the risk of fire hazard found in high-frequency technologies such as the ones using the Qi protocol requiring the system to stop if nearby conducting objects are detected. Also, low-frequency magnetic fields are less impeded by conductive media, which is suitable for charging systems through metal walls or in seawater.
Finally, low-frequency WPT technologies create very few electromagnetic interferences, which is an advantage for critical systems.
CEA is a French government-funded technological research organisation in four main areas: low-carbon energies, defense and security, information technologies and health technologies. A prominent player in the European Research Area, it is involved in setting up collaborative projects with many partners around the world.