CHARGING SYSTEM


  1. SYSTEM CONTROL


    1. Charging control is performed by the hybrid vehicle control ECU.

    2. The hybrid vehicle control ECU controls the output voltage of the DC-DC converter to keep the auxiliary battery at the optimum SOC (battery charging percentage).


      1. The hybrid vehicle control ECU detects the electrical load condition (inverter water pump assembly, battery cooling blower assembly, engine state, etc.).

      2. The battery state sensor assembly detects the auxiliary battery conditions such as voltage, current, temperature, SOC (battery charging percentage), etc.

      3. Based on the electrical load condition and the condition of the auxiliary battery, the hybrid vehicle control ECU calculates the voltage to request and sends a voltage request signal to the DC-DC converter.

  2. FUNCTION


    1. Via LIN communication, the hybrid vehicle control ECU receives information about the auxiliary battery charge/discharge current, etc. detected by the battery state sensor assembly. Based on these signals, conditions such as the auxiliary battery SOC (battery charging percentage), etc. are calculated.

    2. The battery state sensor assembly detects the temperature of the auxiliary battery and sends a signal to the hybrid vehicle control ECU to enable judgment of the conditions for entering constant voltage control mode.

  3. FAIL-SAFE


    1. The ECM stops charging control and the generator switches to the constant voltage generation mode under the following conditions:

      Conditions for Shifting to Constant Voltage Control Mode
      Judgement Condition Reasoning
      Auxiliary Battery SOC Low When the auxiliary battery SOC (battery charging percentage) is low, or when the auxiliary battery temperature is low or high, control is stopped to prevent the SOC (battery charging percentage) of the auxiliary battery from becoming too low. If the auxiliary battery temperature is too low or too high, battery discharge or shortened battery lifespan could result.
      Low or High Auxiliary Battery Temperature

      • Vehicle Cooling System Load High

      • Engine Load High

      		 The voltage changes due to charging control. As this can impact the operation of electrical devices, the system temporarily stops charging control to prevent any perceived abnormality in the operation of these devices.

      • Battery State Sensor Assembly Malfunction

      • Voltage Sensing Failure

      		 If sensor malfunction occurs, charging control is stopped to prevent the SOC (battery charging percentage) of the auxiliary battery from becoming too low.
      LIN Communication Malfunction between Hybrid Vehicle Control ECU and Battery State Sensor Assembly If there is a LIN communication malfunction between the hybrid vehicle control ECU and battery state sensor assembly, charging control is stopped to protect the auxiliary battery and prevent its SOC (battery charging percentage) from becoming too low.