Electronic control valve for HVAC system of vehicle and control method of HVAC system

A control valve apparatus of a heating, ventilation, and air conditioning (HVAC) system and of controlling an angle of a swash plate with respect to a rotation shaft of a compressor in the HVAC system, the control valve apparatus comprising:

• a solenoid member;
• a plunger coupled to the solenoid member and configured to selectively slid according to whether the solenoid member is magnetized;
• a valve body formed integrally with the plunger, and configured to open or close a supply flow path through which a fluid flows into the compressor, a discharge flow path through which a fluid is discharged from the compressor, and a control flow path through a fluid flows to control the angle of the swash plate mounted inside the compressor;
• a diaphragm operating the plunger by a pressure of fluid;
• and
• a return spring engaged to the plunger and configured to return the plunger,
• wherein the solenoid member is applied with power according to a vehicle target cooling load,
• wherein the control valve apparatus is controlled to be opened or closed according to whether the power is applied to the solenoid member and according to a pressure of the fluid supplied to the supply flow path,
• wherein the control valve apparatus is configured to maintain a closed state thereof or is open according to application of the power to the solenoid member and the pressure of the fluid supplied to the supply flow path, and
• wherein when the pressure of the fluid supplied to the supply flow path is less than a setting pressure set to change opening and closing the control flow path, the control valve apparatus is changed to an open state.