What’s needed for the engine to start? That’s right: The battery has to be charged. An intelligent electrical system is required to make sure this happens and that the battery is optimally charged.

Electricity is generated by the alternator integrated in the flywheel of the engine (for example, in the 1B, 1D or 2G engine series). This alternator uses a permanent magnet generator to produce alternating current. Permanent magnet generators have the advantage of being wear-free, maintenance-free and extremely compact. In addition, there are no sparks during operation, which makes them particularly suitable for critical operating conditions.

There are different winding configurations for the stator, such as counter-phase winding or the direct-phase principle. Here we will explain the function of counter-phase winding as an example. The alternator consists of a stationary part, called the stator, and the rotor with magnets. The stator, as the winding part, can be designed in different ways.

Counter-phase winding, as the name suggests, has alternating windings. One half delivers negative voltage; the other half delivers positive voltage. Only two diodes are needed to rectify this alternating voltage. This concept also generates relatively little heat. Governor switches take care of the aforementioned rectification of the current. The rectified charging current is then sent to the battery.

The governor switch also controls the on-demand power output to the consumers or the battery. The governor switch uses the battery voltage as a measured variable. Just before the maximum voltage is reached, the governor switch ensures that the charging current is reduced or switched off, provided that no additional electrical consumers are connected. In this way the governor switch ensures a long battery life and the operability of the Hatz engine.