US 11,946,674 B2
Air conditioning system and cooling method for drive motor thereof
Xi Feng, Shanghai (CN); Shuguang Zhang, Shanghai (CN); Jun Cao, Shanghai (CN); and Hao Zhao, Shanghai (CN)
Assigned to CARRIER CORPORATION, Palm Beach Gardens, FL (US)
Appl. No. 17/254,930
Filed by Carrier Corporation, Palm Beach Gardens, FL (US)
PCT Filed Sep. 11, 2020, PCT No. PCT/US2020/050382
§ 371(c)(1), (2) Date Dec. 22, 2020,
PCT Pub. No. WO2021/050859, PCT Pub. Date Mar. 18, 2021.
Claims priority of application No. 201910863348.6 (CN), filed on Sep. 12, 2019.
Prior Publication US 2022/0196298 A1, Jun. 23, 2022
Int. Cl. F25B 31/00 (2006.01); F25B 1/10 (2006.01); F25B 5/02 (2006.01); F25B 41/22 (2021.01); F25B 49/02 (2006.01); H02P 29/60 (2016.01)
CPC F25B 31/006 (2013.01) [F25B 1/10 (2013.01); F25B 5/02 (2013.01); F25B 41/22 (2021.01); F25B 49/02 (2013.01); H02P 29/60 (2016.02); F25B 2400/05 (2013.01); F25B 2600/2513 (2013.01); F25B 2600/2515 (2013.01); F25B 2700/1933 (2013.01); F25B 2700/2115 (2013.01)] 10 Claims
OG exemplary drawing
 
1. An air conditioning system, comprising:
a main circuit having a multi-stage compressor, a condenser, a throttling element and an evaporator connected by pipelines;
a cooling branch, the inlet of which is connected to the main circuit between the condenser and the throttling element, and the outlet of which is connected to at least one of the first-stage suction port and the intermediate-stage suction port of the multi-stage compressor, wherein the cooling branch flows through the drive motor of the multi-stage compressor, and a regulating valve for controlling the cooling branch is provided on the cooling branch; and
a control module that controls the opening of the regulating valve on the cooling branch based on the temperature of the outlet downstream of the drive motor on the cooling branch and the intermediate suction pressure of the intermediate-stage suction port of the multi-stage compressor;
wherein the cooling branch comprises a first branch and a second branch connected to the multi-stage compressor from downstream of the drive motor on the cooling branch; wherein, the first branch comprises a first valve that controls the opening and closing thereof and a first outlet connected to the first-stage suction port of the multi-stage compressor; and the second branch comprises a second valve that controls the opening and closing thereof and a second outlet connected to the intermediate-stage suction port of the multi-stage compressor.