Control Alternator

The alternator and its charging of the battery are controlled by the central electronic module (CEM) according to signals from the battery monitoring module on battery status. For this function to be possible, battery status is monitored and calculated precisely by the battery monitoring module. The request for charging the battery is sent from the central electronic module (CEM) to the engine control module (ECM) which then controls the alternator.

The engine control module (ECM) calculates engine efficiency (need for torque for power transmission). When the need for torque is low, regardless of what the central electronic module (CEM) requests in terms of voltage from the alternator, the engine control module (ECM) will then take over control of the alternator. This occurs when charging of the battery can take place from the car's kinetic energy, e.g., during engine braking. The engine control module (ECM) sends information to the alternator control module (ACM) on the charge voltage the alternator should maintain.

The engine control module (ECM) sends the status of engine efficiency to the central electronic module (CEM). When engine efficiency is low, i.e. when the engine's torque is required to propel the vehicle, the central electronic module (CEM) takes control of the alternator and calculates the how the alternator should be controlled to minimize the load on the engine.

Depending on the engine's efficiency, power consumption in the vehicle and the battery's status, the alternator is controlled as follows:

• Conventional charging
  • slowly
  • quickly
  • slowly without discharging
• Reconditioning battery
  • slowly
  • quickly
  • slowly without discharging
• Battery identification
  • slowly
  • quickly
  • slowly without discharging
• Brake energy regeneration. Regeneration can occur in the following ways:
  • slowly
  • quickly
  • slowly without discharging