Cooling system and control method therefor

Patent metadata

Field	Value
Publication number	US-11668500-B2
Application number	US-201817261656-A
Country	US
Kind code	B2
Filing date	Jul 27, 2018
Priority date	Jul 27, 2018
Publication date	Jun 6, 2023
Grant date	Jun 6, 2023

Abstract

The present application discloses a cooling system and a control method thereof; the cooling system includes a compressor unit, a condenser, a first solenoid valve, a second solenoid valve, a first throttle valve and a frequency converter; the second solenoid valve and the first throttle valve are connected with the first solenoid valve in parallel after being connected in series with each other; the compressor unit, the condenser, the first solenoid valve and the frequency converter are connected in series to form a first cooling loop; the compressor unit, the condenser, the second solenoid valve, the first throttle valve and the frequency converter are connected in series to form a second cooling loop; and the frequency converter is internally provided with a temperature detection module and a heat exchange module.

First claim

The invention claimed is:

1. A cooling system, comprising a compressor unit, a condenser, a first solenoid valve, a second solenoid valve, a first throttle valve, and a frequency converter, wherein the second solenoid valve and the first throttle valve are connected in series and connected with the first solenoid valve in parallel; the compressor unit, the condenser, the first solenoid valve, and the frequency converter are connected in series to form a first cooling loop; the compressor unit, the condenser, the second solenoid valve, the first throttle valve, and the frequency converter are connected in series to form a second cooling loop; and the frequency converter is internally provided with a temperature detector and a heat exchange module;
wherein if the temperature detector detects that a temperature in the frequency converter is lower than a switching temperature T, the first solenoid valve is opened, the second solenoid valve is closed, the first cooling loop is opened, and the second cooling loop is closed; and
if the temperature detector detects that the temperature in the frequency converter is equal to or higher than the switching temperature T, the first solenoid valve is closed, the second solenoid valve is opened, the first cooling loop is closed, and the second cooling loop is opened.

2. The cooling system according to claim 1 , further comprising a cooling capacity adjustment module, the cooling capacity adjustment module includes at least one cooling capacity adjustment assembly, and each cooling capacity adjustment assembly comprises an electronic expansion valve, and is located between the compressor unit and the frequency converter to adjust the flow of the refrigerant passing through the frequency converter.

3. The cooling system according to claim 2 , wherein at least two cooling capacity adjustment assemblies are provided, and the cooling capacity adjustment assemblies are arranged in parallel.

4. The cooling system according to claim 2 , wherein each cooling capacity adjustment assembly further comprises a third solenoid valve connected in parallel with the electronic expansion valve.

5. The cooling system according to claim 1 , wherein the frequency converter is internally provided with an inverter module, a rectifier module and a reactor.

6. The cooling system according to claim 2 , further comprising an evaporator located between the cooling capacity adjustment assembly and the compressor unit.

7. A control method of the cooling system according to claim 1 , comprising the following steps of:
detecting the temperature in the frequency converter by using the temperature detector;
determining the temperature in the frequency converter is lower than a switching temperature T, and in response:
opening the first solenoid valve, closing the second solenoid valve, opening the first cooling loop, and closing the second cooling loop.

8. A control method of the cooling system according to claim 2 , comprising the following steps of:
detecting the temperature in the frequency converter by using the temperature detector;
determining the temperature in the frequency converter is lower than the switching temperature T, and in response:
opening the first solenoid valve, closing the second solenoid valve, opening the first cooling loop, and closing the second cooling loop; and
controlling an opening degree of the electronic expansion valve according to whether the temperature of the frequency converter exceeds a target temperature range T0 (Ta, Tb) or not, wherein Tb<T; if the temperature detector detects that the temperature of the frequency converter is within the target temperature range T0, maintaining the opening degree of the electronic expansion valve at a predetermined size; if the temperature detector detects that the temperature of the frequency converter is higher than Tb, increasing the opening degree of the electronic expansion valve; if the temperature detector detects that the temperature of the frequency converter is lower than the target temperature range Ta, reducing the opening degree of the electronic expansion valve.

9. A control method of the cooling system according to claim 4 , comprising the following steps of:
detecting the temperature in the frequency converter by using the temperature detector;
determining the temperature in the frequency converter is equal to or higher than the switching temperature T, and in response to determining the temperature in the frequency converter is equal to or higher than the switching temperature T: closing the first solenoid valve, opening the second solenoid valve, closing the first cooling loop, and opening the second cooling loop;
wherein, an opening degree of the electronic expansion valve is controlled according to whether the temperature of the frequency converter exceeds a target temperature range T0 (Ta, Tb) or not, wherein Tb<T; if the temperature detector detects that the temperature of the frequency converter is within the target temperature range T0, the opening degree of the electronic expansion valve is maintained at a predetermined size; if the temperature detector detects that the temperature of the frequency converter is higher than Tb, the opening degree of the electronic expansion valve is increased; if the temperature detector detects that the temperature of the frequency converter is lower than the target temperature range Ta, the opening degree of the electronic expansion valve is reduced; and
the opening and closing of the third solenoid valve is controlled according to a set temperature T1 of a first frequency converter and a set temperature T2 of a second frequency converter, wherein T2<Ta<Tb<T1<T; if the temperature detector detect or detects that the temperature of the frequency converter is higher than the set temperature T1 of the first frequency converter, the third solenoid valve is opened, the opening degree of the electronic expansion valve is continuously increased until reaching a greatest opening degree possible; if the temperature detector detects that the temperature of the frequency converter is lower than the set temperature T2 of the second frequency converter, the third solenoid valve, and afterwards the operation of the opening degree of the electronic expansion valve is controlled by comparing whether the temperature of the frequency converter exceeds the target temperature range T0 or not.

10. The control method of the cooling system according to claim 9 , wherein after the second cooling loop is opened, determining the third solenoid valve is closed and the operating opening degree of the electronic expansion valve is smaller than a set opening degree all the time within a set time, and in response the cooling system is switched to the first cooling loop, and the second cooling loop is closed; during switching, the third solenoid valve is firstly opened, subsequently the first solenoid valve is opened, and then the second solenoid valve is closed to complete the switching.

11. The control method of the cooling system according to claim 10 , wherein the set time is 1 min to 60 min.

12. The control method of the cooling system according to claim 10 , wherein the set opening degree is smaller than or equal to 25% of the greatest opening degree possible.

13. A control method of the cooling system according to claim 1 , comprising the following steps of:
detecting the temperature in the frequency converter by using the temperature detector;
determining the temperature in the frequency converter is equal to or higher than a switching temperature T; and in response,
closing the first solenoid valve, opening the second solenoid valve, closing

Assignees

• Gree Electric Appliances Inc Zhuhai

Inventors

• Liu Hua
• Zhang Zhiping
• Li Hongbo
• Liang Hu
• Liu Xianquan

Classifications

• F25B1/00 Primary

  Compression machines, plants or systems with non-reversible cycle (F25B3/00, F25B5/00, F25B6/00, F25B7/00, F25B9/00 take precedence) · CPC title

• F25B2700/21153

  of electronic components · CPC title

• F25B2700/21154

  of an inverter · CPC title

• H05K7/20945

  Thermal management, e.g. inverter temperature control · CPC title

• F25B49/02

  for compression type machines, plants or systems · CPC title