MAHLE permanent-magnet alternating current generators are connected directly to the combustion engine crankshaft. They generate electricity that can be used to charge the battery, for instance, or to power electronic control units. The external circumference of the alternator is fitted with a ring gear that is probed by a sensor. As the alternator rotates, the probe relays signals to the ignition management system, which are used by the electronics to calculate the engine speed. The moment of inertia of the rotor in the alternator has a stabilizing effect on the engine speed, and the combustion engine runs more smoothly as a result. MAHLE voltage regulators convert the alternating current generated in the alternator to direct current, while at the same time ensuring a constant battery charge voltage.
MAHLE alternators thus combine several engine functions, reducing complexity and cost, as well as weight.