Variable refrigerant flow air conditioning system, control method thereof, and computer-readable storage medium

Patent metadata

Field	Value
Publication number	US-12359837-B2
Application number	US-202318132670-A
Country	US
Kind code	B2
Filing date	Apr 10, 2023
Priority date	Oct 13, 2020
Publication date	Jul 15, 2025
Grant date	Jul 15, 2025

Abstract

A variable refrigerant flow (VRF) air conditioning system, a control method thereof, and a computer-readable storage medium are provided. When the VRF air conditioning system is cooling, indoor units in an operating state are obtained. Indoor units with humidity demand and indoor units without humidity demand in the operating state are obtained. A ratio of humidity demand is determined according to an output nominal value of each indoor unit in the operating state. The ratio can include a ratio of a total output nominal value of indoor units with humidity demand to a total output nominal value of indoor units without humidity demand. When the ratio is greater than a preset ratio, a rotation speed of an outdoor fan can be adjusted according to an outdoor environment temperature.

First claim

What is claimed is:

1. A method for controlling a variable refrigerant flow (VRF) air conditioning system, comprising:
obtaining indoor units in an operating state in response to that the VRF air conditioning system is cooling;
obtaining indoor units with humidity demand and indoor units without humidity demand among the indoor units in the operating state;
determining a ratio of humidity demand according to an output nominal value of each indoor unit in the operating state, wherein the ratio of the humidity demand comprises a ratio of a total output nominal value of the indoor units with humidity demand to a total output nominal value of the indoor units without humidity demand, or the ratio of the humidity demand comprises a ratio of the total output nominal value of the indoor units with humidity demand to the total output nominal value of the indoor units with humidity demand and the indoor units without humidity demand; and
in response to that the ratio of the humidity demand is greater than a preset ratio, adjusting a rotation speed of an outdoor fan according to an outdoor environment temperature and/or adjusting a frequency of a compressor according to a preset humidity corresponding to the indoor unit in the operating state.

2. The method for controlling the VRF air conditioning system according to claim 1 , wherein the obtaining the indoor units with humidity demand and the indoor units without humidity demand among the indoor units in the operating state comprises:
detecting a state of a working space corresponding to the indoor units in the operating state; and
obtaining the indoor units with humidity demand and the indoor units without humidity demand among the indoor units that are in the operating state and the state of the working space is occupied.

3. The method for controlling the VRF air conditioning system according to claim 1 , wherein the adjusting the frequency of the compressor according to the preset humidity corresponding to the indoor unit in the operating state comprises:
obtaining a temperature difference between a current indoor temperature and a corresponding preset temperature corresponding to each indoor unit in the operating state; and
adjusting the frequency of the compressor according to the preset temperature and the preset humidity of the indoor unit corresponding to a minimum temperature difference.

4. The method for controlling the VRF air conditioning system according to claim 3 , wherein the adjusting the frequency of the compressor according to the preset temperature and the preset humidity of the indoor unit corresponding to the minimum temperature difference comprises:
obtaining a target dew point temperature according to the preset temperature and the preset humidity of the indoor unit corresponding to the minimum temperature difference;
obtaining a target suction saturation temperature according to the target dew point temperature; and
adjusting the frequency of the compressor according to an actual suction saturation temperature of the compressor and the target suction saturation temperature.

5. The method for controlling the VRF air conditioning system according to claim 1 , further comprising:
in response to that the ratio of the humidity demand is greater than the preset ratio, adjusting an opening degree of an electronic expansion valve of each indoor unit in the operating state according to an exhaust temperature of the compressor.

6. The method for controlling the VRF air conditioning system according to claim 5 , wherein the adjusting the opening degree of the electronic expansion valve of each indoor unit in the operating state according to the exhaust temperature of the compressor comprises:
in response to that the exhaust temperature is greater than or equal to an exhaust temperature threshold, adjusting the opening degree of the electronic expansion valve of each indoor unit in the operating state according to a preset opening degree adjustment value; or
in response to that the exhaust temperature is lower than the exhaust temperature threshold, adjusting the opening degree of the electronic expansion valve of each indoor unit in the operating state according to an exhaust superheat degree.

7. The method for controlling the VRF air conditioning system according to claim 1 , wherein the adjusting the rotation speed of the outdoor fan according to the outdoor environment temperature comprises:
obtaining a target heat exchange temperature according to the outdoor environment temperature, the target heat exchange temperature being greater than the outdoor environment temperature; and
adjusting the rotation speed of the outdoor fan according to the target heat exchange temperature.

8. The method for controlling the VRF air conditioning system according to claim 7 , wherein the adjusting the rotation speed of the outdoor fan according to the target heat exchange temperature comprises:
obtaining an exhaust saturation temperature of the compressor, the exhaust saturation temperature being a saturation temperature corresponding to an exhaust pressure of the compressor;
in response to that the exhaust saturation temperature is less than or equal to the target heat exchange temperature, reducing the rotation speed of the outdoor fan; or
in response to that the exhaust saturation temperature is greater than the target heat exchange temperature, increasing the rotation speed of the outdoor fan.

9. The method for controlling the VRF air conditioning system according to claim 1 , further comprising:
in response to that the ratio of the humidity demand is less than the preset ratio, adjusting the opening degree of the electronic expansion valve of each indoor unit according to an outlet temperature of an indoor heat exchanger of each indoor unit in the operating state.

10. The method for controlling the VRF air conditioning system according to claim 9 , further comprising:
in response to adjusting the opening degree of the electronic expansion valve of the indoor unit according to the outlet temperature of the indoor heat exchanger of each indoor unit in the operating state, obtaining a current indoor humidity corresponding to the indoor unit with humidity demand;
in response to that the current indoor humidity corresponding to the indoor unit with humidity demand is lower than a first humidity, controlling a humidifying device corresponding to the indoor unit with humidity demand to operate; and
in response to that the humidifying device is operating, if the current indoor humidity corresponding to the indoor unit with humidity demand is greater than a second humidity, controlling the humidifying device to stop operating, the second humidity being greater than the first humidity.

11. A variable refrigerant flow (VRF) air conditioning system, comprising:
a processor; and
a memory storing a program for controlling the VRF air conditioning system, the program, when executed, causing the processor to implement the method for controlling the VRF air conditioning system according to claim 1 .

12. A non-transitory computer-readable storage medium storing a program for controlling a variable refrigerant flow (VRF) air conditioning system, wherein the program, when executed by a processor, implements the method for controlling the VRF air conditioning system according to claim 1 .

Assignees

• Midea group wuhan refrigeration equipment co ltd
• Gd Midea Air Conditioning Equipment Co Ltd

Inventors

• Tao kui
• Li Shunquan

Classifications

• F24F2110/20

  Humidity · CPC title

• F24F11/871

  by controlling outdoor fans · CPC title

• F24F11/65

  for selecting an operating mode · CPC title

• F24F3/065

  with a plurality of evaporators or condensers · CPC title

• F24F2110/12

  of the outside air · CPC title