US 12,173,944 B2
Refrigerating and air-conditioning apparatus
Kazunori Sakanobe, Tokyo (JP); Kenta Yuasa, Tokyo (JP); Yasuhiko Wada, Tokyo (JP); and Chitose Tanaka, Tokyo (JP)
Assigned to Mitsubishi Electric Corporation, Tokyo (JP)
Appl. No. 18/003,172
Filed by MITSUBISHI ELECTRIC CORPORATION, Tokyo (JP)
PCT Filed Aug. 21, 2020, PCT No. PCT/JP2020/031592
§ 371(c)(1), (2) Date Dec. 23, 2022,
PCT Pub. No. WO2022/038764, PCT Pub. Date Feb. 24, 2022.
Prior Publication US 2023/0251014 A1, Aug. 10, 2023
Int. Cl. F25B 49/02 (2006.01); F24F 11/41 (2018.01); F25B 47/02 (2006.01); F25B 13/00 (2006.01)
CPC F25B 49/025 (2013.01) [F24F 11/41 (2018.01); F25B 47/025 (2013.01); F25B 13/00 (2013.01); F25B 2347/02 (2013.01); F25B 2600/021 (2013.01); F25B 2700/21152 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A refrigerating and air-conditioning apparatus comprising:
a refrigerant circuit in which a compressor having a built-in motor, a first heat exchanger, an expansion device, a second heat exchanger, and a four-way valve are connected to each other by pipes to allow refrigerant to circulate through the refrigerant circuit;
a temperature sensor configured to measure a temperature of the compressor;
an inverter configured to control the motor, and
a heat generation control unit being provided in the inverter and configured to
increase a temperature of the compressor when the heat generation control unit detects a decrease in a value measured by the temperature sensor during a defrosting operation performed on the first heat exchanger, and
use a value of an excitation-current command for the motor as a controlled variable, and generate a negative excitation-current command.