Method of controlling a vehicle thermal management system

A method of controlling a vehicle thermal management system, the method comprising:

• determining, by a controller, a vehicle required heat amount based on an amount of heat required for cabin heating and an amount of heat required for battery warming-up in a heating mode of a heating, ventilation, and air conditioning (HVAC) subsystem;
• determining, by the controller, whether a second predetermined threshold is greater than a first predetermined threshold based on the vehicle required heat amount being greater than the first predetermined threshold;
• controlling, by the controller, operations of the HVAC subsystem and a coolant subsystem to minimize a work quantity of a compressor of the HVAC subsystem and minimize a heat release amount of a refrigerant circulating in the HVAC subsystem based on the second predetermined threshold being greater than the first predetermined threshold;
• determining, by the controller, a heat absorption amount of the refrigerant, wherein the heat absorption amount of the refrigerant is the amount of heat absorbed by the refrigerant from a coolant, outdoor air, and the compressor;
• and
• increasing the work quantity of the compressor of the HVAC subsystem by a predetermined value based on the determined heat absorption amount of the refrigerant being greater than the heat release amount of the refrigerant,
• wherein the first predetermined threshold is a maximum heat release amount of the refrigerant when the HVAC subsystem operates in a first heating mode, and
• wherein the second predetermined threshold is a maximum heat release amount of the refrigerant when the HVAC subsystem operates in a second heating mode.