"We deliberately use standard components that are already available on the mass market," explained Marco Jung, deputy head of the converter technology department at Fraunhofer IWES.
Another advantage is the specially designed power electronics and coil systems, which means that the system works efficiently even when the coil in the car is 20cm from the coil in the road.
"Even with an air gap of 20cm, we achieve an efficiency of between 93 and 95%, and do so across the entire power range, from 400W to 3.6kW," said Dr René Marklein, project manager at Fraunhofer IWES.
As well as charging the batteries, the system can also discharge them. This can help to stabilise the general power grid when there is a surplus thanks to all day sun or strong winds over-charging the grid. The researchers say that car batteries could be used as a sort of buffer, the surplus electricity could be stored there temporarily and then fed back into the grid when the sun clouds over or the winds die down.
Current electric cars have a limited range. However, researchers at the Fraunhofer Institutes for Manufacturing Technology and Advanced Materials IFAM and for Transportation and Infrastructure Systems IVI say it will become possible to charge cars while they are moving. This team has constructed a 25m test route along which coils have been set into the road. The team succeeded in driving an electric vehicle along the strip at a moderate speed while simultaneously charging its battery.
