Nuremberg. Many consider hybrids to be a niche product because of the space problems caused by having a vehicle with two power plants: one electric and the other internal combustion.
The electronic components in a hybrid are so large that they don't fit easily into the engine compartment, which has limited designers' possibilities for vehicle configurations.
But researchers here at ZKLM, a satellite of the Erlanger Fraunhofer Institute for Integrated Systems and Component Technology, have found a space-saving solution.
They have developed a ring-shaped electronics assembly that fits in the transmission bell housing along with the electric motor.
The space near the coupling can hold a 50kw electric motor plus all the necessary electronics.
Until now, the electronics more or less have been housed in large boxes wherever there was room in the engine compartment. The units all were hooked together with cables and connectors.
"That is a problematical approach because it is complicated and expensive, and cable connections are especially prone to failure," said Martin Maerz, manager of ZKLM.
To merge electronics and mechanics, ZKLM's experts first had to develop completely new units. The engineers replaced the conventional pot-shaped capacitor, which stores the energy to supply the electric motor's magnet coils, with a foil coil. It is flexible and easily positioned inside the bell housing.
This work resulted in a banana-shaped performance module, instead of a rectangular one. The new module fits perfectly in the housing. It also converts direct current into the alternating current that the engine needs. Direct current is used inside the vehicle.
The researchers have completed the third generation of their so-called power conversion engine.
Currently, the Nuremberg team is working on increasing the reliability of the engine. For example, it is determining how the individual units respond to thermal loads.
Maerz believes the new technology "will come into use beginning in 2012."