US 12,442,573 B2
Air conditioning system and control method thereof
Peng Yan, Shandong (CN); Min Zhou, Shandong (CN); Yang Sun, Shandong (CN); and Fei Han, Shandong (CN)
Assigned to QINGDAO HISENSE HITACHI AIR-CONDITIONING SYSTEMS CO., LTD., Qingdao (CN)
Filed by QINGDAO HISENSE HITACHI AIR-CONDITIONING SYSTEMS CO., LTD., Shandong (CN)
Filed on Jan. 5, 2024, as Appl. No. 18/405,707.
Application 18/405,707 is a continuation of application No. PCT/CN2021/140321, filed on Dec. 22, 2021.
Claims priority of application No. 202110887207.5 (CN), filed on Aug. 3, 2021.
Prior Publication US 2024/0151441 A1, May 9, 2024
Int. Cl. F25B 41/31 (2021.01); F24F 1/0059 (2019.01); F25B 40/02 (2006.01); F25B 49/02 (2006.01)
CPC F25B 41/31 (2021.01) [F24F 1/0059 (2013.01); F25B 40/02 (2013.01); F25B 49/02 (2013.01); F25B 2600/2513 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An air conditioning system, comprising an outdoor unit and at least one indoor unit, wherein
the outdoor unit includes:
a compressor;
an outdoor heat exchanger;
a first expansion valve; and
a refrigerant phase change device, including:
a subcooling heat exchanger having a main path and an auxiliary path; the subcooling heat exchanger being connected to the first expansion valve and the outdoor heat exchanger and located between the first expansion valve and the outdoor heat exchanger; and
a third expansion valve, both ends thereof being connected to the first expansion valve and the subcooling heat exchanger; and
an indoor unit includes an indoor heat exchanger and a second expansion valve; the second expansion valve being connected to the indoor heat exchanger and the first expansion valve and located between the indoor heat exchanger and the first expansion valve, wherein
in a cooling mode, the outdoor unit is configured to:
adjust an opening degree of the first expansion valve according to a relationship between a first difference and a first preset value, so as to make the first difference satisfy the first preset value; wherein the first difference is a difference between a current subcooling degree of the main path of the subcooling heat exchanger and a target subcooling degree of the main path of the subcooling heat exchanger;
adjust an opening degree of the second expansion valve according to a relationship between a second difference and a second preset value, so as to make the second difference satisfy the second preset value; wherein the second difference is a difference between a current superheat degree of the indoor heat exchanger and a target superheat degree of the indoor heat exchanger; and
adjust an opening degree of the third expansion valve according to a relationship between a third difference and a third preset value, so as to make the third difference satisfy the third preset value; wherein the third difference is a difference between a current superheat degree of discharge of the compressor and a target superheat degree of the discharge of the compressor.