Fraunhofer Institute Develops Vertical Wireless Charging

3 years ago by Mark Kane 10

Charging electric cars by induction is still a distant vision. By installing the charging system at the front of the vehicle, scientists have found a new efficient and cost-effective approach.© Fraunhofer IISB

Charging electric cars by induction is still a distant vision. By installing the charging system at the front of the vehicle, scientists have found a new efficient and cost-effective approach.© Fraunhofer IISB

Evatran PLUGLESS Wireless Charging System

Evatran PLUGLESS Wireless Charging System

The Fraunhofer Institute for Integrated Systems and Device Technology IISB in Erlangen, Germany recently presented an interesting new concept on wireless charging.

Instead of the typical pad on the ground, IISB developed a vertical unit and an on-board adapter for under the front license plate.

Researchers took up this topic because “cables are annoying.”  Dr. Bernd Eckardt, head of the Vehicle Power Electronics department at the IISB stated:

“Cables are annoying, especially in winter or when it’s raining. Whatever gets on the cable – snow, sludge, water – also gets on your hands.”

But why go vertical? Because the air-gap is smaller then, which enables use of smaller, less expensive coils and increases the efficiency. The yellow prototype on the photo has 3 kW and 95% efficiency, but IISB is already working on more power.

Such a solution skips over several issues:

“Researchers from the scientific and industrial communities have been working for several years to find ways to use induction to charge electric vehicles. The current approach involves mounting induction coils on the underside of the vehicle and installing charging stations in the ground. But this brings with it a number of significant challenges. The coils need to be very powerful for the method to work because of the significant gap of up to 15 cm between car and ground. Powerful coils are large in size – and large coils are expensive, which pushes up costs. There is also the problem of objects or animals impeding the charging process by blocking the transmission of power. Cats, for example, are attracted by the gentle warmth emitted from the charging station in the ground, and so see this as a comfortable resting place. Another particularly problematic issue is that metallic paper such as chewing-gum wrappers or cigarette packaging can blow under the car and into the induction zone, where it can get so hot that it bursts into flame.”

Out first thought is that car could hit this thing while parking, but the primary coil is in a plastic housing and the charging column bends backwards if pushed by the vehicle.

“Researchers at the IISB began pursuing an alternative approach in a bid to resolve these problems. Working as part of the Energie Campus Nürnberg research platform it took them less than a year to develop a system for charging electric vehicles from the front end (http://www.encn.de). Since this allows the car to be driven much closer to the induction source – essentially touching it – the coils themselves are much smaller in diameter than in the floor-based version, coming in at 10 instead of 80 cm across. The system is more efficient, more cost-effective and makes it less probable that obstacles will disrupt the flow of energy. The charging column is approximately waist-high and made of plastic. It bends backwards if pushed by the vehicle, and is even designed to flip down and out the way if the pressure applied is too strong. “The car could drive over it if necessary. Touching the charging station causes no damage to the car body,” says Eckardt. The coils are arranged in such a way that charging can take place even if the driver has not positioned the vehicle exactly in front of and centrally to the column. Clusters of coils that overlap vertically in the column and horizontally behind the license plate allow the current to flow irrespective of the vehicle’s size or height.”

Dr. Bernd Eckardt adds:

“We’ve been consistently upping the system’s performance over the past year, and are now in possession of a prototype that is able to transmit three kilowatts (kW) at an overall efficiency of 95 percent. Today’s electric car models can be recharged overnight.”

“Nowadays, charge spots are offered as part of the sales package when customers buy an electric vehicle. This technology will only become a mass product if the price is right.”

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10 responses to "Fraunhofer Institute Develops Vertical Wireless Charging"

  1. Driverguy01 says:

    Any technology that gets rid of the plug is good, i wish them success as soon as possible. I’ve had Plugless for five months and dont miss that plug, at all!

  2. It’s an interesting approach and solves several challenges with floor mount, but throws interoperability out the window.

    That’s a problem for an industry struggling to close the gap on wireless charging standards.

  3. Bloggin says:

    Maybe what’s needed for the floor mounted inductive charger is a smart system that automatically lifts the charge unit up to meet the car, which would create a physical connection(dock) and increase the charging speed potential.

    This would also eliminate anything getting between the charging unit and the car.

    But creating another cumbersome standard does not seem necessary.

    1. sven says:

      Or one that lowers from the car to meet the floor-mounted pad. And make the pad flush with the pavement.

  4. DaveMart says:

    For European cities the great point about inductive charging is that it can be buried under the road, without obtrusive and obstructive street furniture on crowded pavements.

    This loses that advantage.

  5. ffbj says:

    True. Mainly for garages.

  6. TomArt says:

    Since I’m going to buy a Tesla, I would only be concerned about my home, for the most part, and for the SCs. I don’t have a garage, or a driveway, but I do have an assigned parking spot directly in front of my townhouse. Having the car plugged in, every night, all year ’round, is possible but not preferred in the mid-Atlantic climate of the US. Any sort of unobtrusive, reliable and efficient inductive charging would be a fantastic alternative to an RV outlet on a post – then having a cable laying around while the car is charging, and then to have a neighbor trip over the cable and sue me…and that’s assuming that I could convince the HOA do put the plug there at all!

    Under the car is practical and visually ideal, but something like this would work pretty well, too, I think, for my situation.

    Hopefully, a reasonable solution will be on sale, by Tesla or someone else, by the time my Model III is delivered. 🙂

    1. TomArt says:

      *for the HOA to permit me to put a plug there at all!

  7. Phr3d says:

    Reasonable-sized (TBD) in ground with in-vehicle coil/plate on articulating arm seems the best way to my logic. Computer informs driver if they are ‘in range’, done, shop, repeat. Billed, if necessary, to VIN-holder account.

  8. Priusmaniac says:

    It is an interesting alternative, but I still wonder why there is not more done in the area of simple secured contacts on the ground. Contacts give a 100% yield and having them secured (through serial high weight switches under both front wheels or through pure electronics) makes it perfectly safe. In more the contacts can be very wide and with a large section so that hypercharge even at a low voltage becomes possible. Of course contacts on the ground would not really be on the ground but rather on top of a low height half cylinder. An additional kind of hard plastic brush around the car contacts would further prevent physical access during charging.