Their number has increased immensely and a motor car without them, is simply unimaginable. They do their jobs without attracting any attention, they open doors, tailgates, and position the seats and the steering wheel. The adjusting of the flaps, e.g., in the air-conditioning or the inlet port is their passion.

At this point, we arrive at the actual electric motors themselves, which we hardly notice. They eject the CD or bring the safety belt into position if there's no B-pillar. They even alter the cam-controller, e.g., in BMWs. Apparently the real actuation of valves is too complicated.

In the drive-train, they are responsible for the clutches. This may be the task of distributing the torque from the front to the rear or from the left side to the right side. They can't quite manage the actual clutch itself. In this case they are still lacking the sensitivity, after all, when parking in reverse the clutch should not be abruptly and suddenly engaged.

Even the brakes can be applied by an electric motor, indeed, in this case, often as a hand- or parking-brake. As far as the steering is concerned, it outranks the hydraulics by miles. Although converting chemical- into electric energy is not particularly favourable from an energetic point of view, this however occurs fairly rarely when driving on a motorway.

With pneumatics or hydraulics a certain amount of pressure must always be kept up. This takes energy, even when the device is not being used. The big thing nowadays, seems to be the supporting role, either in a hybrid- or an electro-model. In the end, even the hydrogen-drive is an electrically powered drive-train.

We've already dealt with the purely electrically powered drive-train in part 1. Because of the necessary battery capacity, it's not yet all that interesting. It does however, become interesting, when used in cooperation with the combustion engine. In this case, it offers itself for use directly on the axle-drive or even for the turbo-charger. In both cases it is possible for an electric motor to be used as a power unit and it can also function as a generator.

What we need are fuel saving engines, whose somewhat phlegmatic acceleration can be improved by the addition of an electric motor. At the moment, we'll still have to do without large batteries because of their weight. Perhaps the 48V-equipment will suffice if the demands are kept low. The electric motor could be installed in place of the generator, thus supporting the engine through a belt-drive. 12/14