Vehicle thermal management system using two-port type integrated thermal management valve and cooling circuit control method of vehicle thermal management system

A cooling circuit control method of a vehicle thermal management system, comprising:

• supplying coolant of an engine cooling system to an engine through an engine coolant inlet that is connected to an outlet end of a water pump by a first coolant line of the engine cooling system;
• guiding coolant of the engine circulated from an integrated thermal management valve (ITM) to the water pump and a radiator through an engine head coolant inlet and an engine block coolant inlet, the coolant flowing out toward the radiator through a radiator outlet flow path is distributed, the coolant flowing out toward heat exchangers including one or more among a heater core, an EGR cooler, an oil warmer, an ATF warmer, and an exhaust heat recovery system (EHRS) through a heat exchanger outlet flow path is distributed, and a coolant branch flow path connected to the water pump is connected to the oil warmer,
• supplying to the exhaust heat recovery system (EHRS) a coolant flow to the coolant branch flow path, and regulating the coolant flow with respect to the oil warmer, and
• performing an engine coolant control mode of the vehicle thermal management system including any one of a flow stop control, a micro flow rate control, a heater flow rate control, a fuel efficiency priority control, and a high load control under a valve opening control of the ITM by a valve controller,
• wherein the valve controller is configured to perform a coolant by pass flow of the coolant branch flow path joined to the oil warmer and the auto transmission fluid (ATF) warmer through the EHRS under a driving control of the water pump in the warm-up conditions.