Apparatus and method for controlling alternator of vehicle

An apparatus for controlling an alternator of a vehicle comprising:

• an alternator configured to provide a battery and at least one electronic device with a voltage using rotational force of an engine;
• and
• a regulator configured to control an output voltage of the alternator at a target voltage,
• wherein the regulator determines a target PWM duty cycle by calculating a difference between the target voltage and a voltage of the alternator, and variably controls a slope indicating a speed arriving at the target PWM duty cycle at a current PWM duty cycle.

A method for controlling an alternator of a vehicle configured to generate electricity using rotational force of an engine comprising:

• receiving a target voltage from an electronic control unit (ECU);
• determining a target PWM duty cycle by comparing a current output voltage of the alternator with the target voltage;
• receiving a threshold duty cycle from the ECU;
• comparing a current PWM duty cycle with the threshold duty cycle;
• and
• controlling a slope indicating a speed arriving at the target PWM duty cycle when the current PWM duty cycle is higher than the threshold duty cycle.