Method for controlling heating of hybrid vehicle

A method for controlling heating of a hybrid vehicle having a duct flowing air into the indoor of the hybrid vehicle from the outside, a heater core for circulating the coolant heated from an engine inside the duct, a positive temperature coefficient (PTC) heater heated by the power supplied from a high-voltage battery of the hybrid vehicle inside the duct, and a controller, comprising:

• operating, by the controller, the engine and the PTC heater, and heating the air flowing into the indoor of the hybrid vehicle through the duct;
• and
• changing, by the controller, the voltage supplied to the PTC heater from a low voltage DC-DC converter (LDC) based on a state of the engine and an auxiliary battery for supplying power to an electric component of the vehicle to apply power to the PTC heater,
• determining, by the controller, a high electric load target voltage by determining a target output voltage to be output from the LDC to the PTC heater based on the state of the engine and the auxiliary battery for supplying power to the electric component of the vehicle,
• wherein the determining of the high electric load target voltage includes:
• calculating, by the controller, a correction voltage to be corrected based on the state of the engine and the auxiliary battery with respect to a reference voltage that has been set to be applied to the PTC heater as an initial condition;
• calculating, by the controller, a target voltage by adding the correction voltage to the reference voltage;
• and
• determining, by the controller, the target output voltage by setting the calculated target voltage as a target output voltage applied to the PTC heater,
• between calculating the target voltage and determining the target output voltage, setting, by the controller, a voltage range that confirms whether the calculated target voltage is between the maximum voltage and the minimum voltage capable of being output from the LDC to the PTC heater;
• setting, by the controller, the maximum voltage as the target output voltage when the calculated target voltage is greater than the maximum voltage;
• and
• setting, by the controller, the minimum voltage as the target output voltage when the calculated target voltage is less than the minimum voltage.