Multi-online system

Patent metadata

Field	Value
Publication number	US-2018017271-A1
Application number	US-201515329847-A
Country	US
Kind code	A1
Filing date	Dec 22, 2015
Priority date	Mar 31, 2015
Publication date	Jan 18, 2018
Grant date	—

Abstract

A multi-split system includes an outdoor unit, a distribution device, and a plurality of indoor units. The distribution device includes a gas-liquid separator, a first heat exchange assembly, a first electronic expansion valve, a second heat exchange assembly, a second electronic expansion valve, a third electronic expansion valve connected in parallel with the second electronic expansion valve. When the flow rate of the refrigerant passing through the first electronic expansion valve is greater than a first preset value, the distribution device is configured to calculate a value of superheat degree according to the outlet temperature of the indoor heat exchanger of each cooling indoor unit and the temperature of the refrigerant flowing into the second heat exchange assembly, and to perform a PI control over the second electronic expansion valve and the third electronic expansion valve according to the value of superheat degree.

First claim

1 . A multi-split system, comprising an outdoor unit, a distribution device, and a plurality of indoor units, wherein
the distribution device comprises a gas-liquid separator, a first heat exchange assembly, a first electronic expansion valve, a second heat exchange assembly, a second electronic expansion valve, a third electronic expansion valve connected in parallel with the second electronic expansion valve, in which the distribution device is configured to acquire a flow rate of a refrigerant passing through the first electronic expansion valve, and when the flow rate of the refrigerant passing through the first electronic expansion valve is greater than a first preset value, the distribution device is configured to acquire an outlet temperature of an indoor heat exchanger of each cooling indoor unit of the plurality of indoor units and a temperature of the refrigerant flowing into the second heat exchange assembly respectively, and to calculate a value of superheat degree according to the outlet temperature of the indoor heat exchanger of each cooling indoor unit and the temperature of the refrigerant flowing into the second heat exchange assembly, and to perform a PI control over the second electronic expansion valve and the third electronic expansion valve according to the value of superheat degree.

2 . The multi-split system according to claim 1 , wherein when the flow rate of the refrigerant passing through the first electronic expansion valve is less than a second preset value, the distribution device is further configured to acquire a temperature of the refrigerant discharged to the outdoor unit from the first heat exchange assembly, and to calculate the value of superheat degree according to the temperature of the refrigerant flowing into the second heat exchange assembly and the temperature of the refrigerant discharged to the outdoor unit from the first heat exchange assembly, in which the second preset value is less than the first preset value.

3 . The multi-split system according to claim 1 , wherein the distribution device calculates the value of superheat degree according to following formula:
ΔSH=T 2 b Average−i Tm2,
in which T2bAverage is an average value of the outlet temperature of the indoor heat exchanger of each cooling indoor unit, and Tm2 is the temperature of the refrigerant flowing into the second heat exchange assembly.

4 . The multi-split system according to claim 2 , wherein the distribution device calculates the value of superheat degree according to following formula:
ΔSH=Tm 3− Tm 2,
in which Tm3 is the temperature of the refrigerant discharged to the outdoor unit from the first heat exchange assembly, and Tm2 is the temperature of the refrigerant flowing into the second heat exchange assembly.

5 . The multi-split system according to claim 1 , wherein the multi-split system works under a main cooling mode.

6 . The multi-split system according to claim 1 , wherein the outlet temperature of the indoor heat exchanger of each cooling indoor unit is detected by a temperature sensor provided at an outlet of the indoor heat exchanger of each cooling indoor unit, and the temperature of the refrigerant flowing into the second heat exchange assembly is detected by a temperature sensor provided at an outlet of the second electronic expansion valve.

7 . The multi-split system according to claim 2 , wherein the multi-split system works under a main cooling mode.

8 . The multi-split system according to claim 3 , wherein the multi-split system works under a main cooling mode.

9 . The multi-split system according to claim 4 , wherein the multi-split system works under a main cooling mode.

Assignees

• Gd Midea Heating & Ventilating Equipment Co Ltd
• Midea Group Co Ltd

Inventors

• Luo Bin
• Chen Junwei

Classifications

• F25B49/02

  for compression type machines, plants or systems · CPC title

• F24F11/30

  for purposes related to the operation of the system, e.g. for safety or monitoring · CPC title

• F24F3/06 Primary

  characterised by the arrangements for the supply of heat-exchange fluid for the subsequent treatment of primary air in the room units · CPC title

• F25B2313/029

  Control issues · CPC title

• F24F11/89

  Arrangement or mounting of control or safety devices · CPC title