Charging System: Description and Operation

The charging system is a system which charges battery charged at a constant level during varying the battery with the generator output to keep the electrical load.








OPERATION
Rotation of the excited field coil generates AC voltage in the stator.

This alternating current is rectified through diodes to DC voltage having a waveform shown in the illustration at left. The average output voltage fluctuates slightly with the generator load condition.

When the MFI relay (ASD relay) is on and the control circuit is grounded by the powertrain control module (PCM), current flows to the field coil, initial energization of the field coil. The stator coil starts to generate power after the engine is started.

The generator output voltage rises as field current increases and falls as field current decreases.

Accordingly, when the battery positive voltage reaches target voltage value the PCM turns the field current off. When the battery positive voltage is below target value*, the PCM turns the field current on to maintenance generator voltage at a constant level. If the field current is constant, the generator output voltage will increase along with increases in engine speed.

*: The target voltage is programmed in the PCM according to battery temperature.