Air conditioning system, vehicular air conditioning system and control method of vehicular air conditioning system

Abstract

An air conditioning system comprises a compressor 2 which compresses a refrigerant made of carbon dioxide, a radiator 4 which radiates heat of the refrigerant compressed by the compressor 2, an expansion valve 5 which decompresses the refrigerant which dissipated heat by the radiator 4 and which can control a refrigerant pressure on the outlet side of the radiator 4, an evaporator 7 which evaporates the refrigerant decompressed by the expansion valve 5, a sensor 13 which detects temperatures of a surface of a pipe through which a high pressure refrigerant on the outlet side of the radiator passes, and a control apparatus 23 which calculates a target refrigerant pressure on the outlet side of the radiator 4 based on a value detected by the sensor to control the expansion valve 5. The control apparatus corrects the target refrigerant pressure on the outlet side of the radiator 4 corresponding to refrigerant temperatures. With this configuration, even if the temperature of the pipe surface is different from the actual refrigerant temperature, the air conditioning system can be controlled under an appropriate target refrigerant pressure.

Dependencies are inferred from the claim text.