Refrigerator and method for controlling a compressor based on temperature of storage compartment

Patent metadata

Field	Value
Publication number	US-11226145-B2
Application number	US-201916694539-A
Country	US
Kind code	B2
Filing date	Nov 25, 2019
Priority date	Nov 26, 2018
Publication date	Jan 18, 2022
Grant date	Jan 18, 2022

Abstract

A method for controlling a refrigerator includes turning on a compressor to operate with a predetermined cooling power for cooling a storage compartment, turning off the compressor when a temperature of the storage compartment reaches a temperature equal to or lower than a first reference temperature, and turning on the compressor again when the temperature of the storage compartment reaches a temperature equal to or higher than a second reference temperature higher than the first reference temperature. In the turning on the compressor again, the compressor is operated with a cooling power determined based on an on slope, which is a temperature change slope of the storage compartment during an on time of the compressor, and an off slope, which is a temperature change slope of the storage compartment during an off time of the compressor.

First claim

What is claimed is:

1. A method for controlling a refrigerator having a compressor and a storage compartment, comprising:
turning the compressor on to operate with a predetermined cooling power for cooling the storage compartment;
determining that a temperature of the storage compartment has decreased to a first reference temperature
turning the compressor off when the temperature of the storage compartment is determined to have decreased to the first reference temperature;
determining that the temperature of the storage compartment has increased to a second reference temperature, the second reference temperature being higher than the first reference temperature, and
turning the compressor on again when the temperature of the storage compartment is determined to have increased to the second reference temperature,
wherein the turning of the compressor on again includes:
determining a cooling power for the compressor based on an on slope and an off slope, the on slope being a temperature change slope of the storage compartment during an on time of the compressor in which the compressor is turned on, and the off slope being a temperature change slope of the storage compartment during an off time of the compressor in which the compressor is turned off, and
operating the compressor at the determined cooling power,
wherein the cooling power of the compressor is determined based on a comparison of a predetermined reference value and a slope ratio of the on slope to the off slope.

2. The method of claim 1 , wherein when the slope ratio is equal to the reference value, the cooling power of the compressor is determined to be maintained at the predetermined cooling power,
wherein when the slope ratio is larger than the reference value, the cooling power of the compressor is determined to be reduced to be less than the predetermined cooling power, and
wherein when the slope ratio is less than the reference value, the cooling power of the compressor is determined to be increased to be more than the predetermined cooling power.

3. The method of claim 2 , wherein an operation rate is a ratio of the on time of the compressor to a sum of the on time of the compressor and the off time of the compressor, and
wherein the reference value is defined as:
operation rate/(1−(operation rate)).

4. The method of claim 3 , wherein the operation rate is a predetermined value and is a fixed value.

5. The method of claim 2 , wherein when the slope ratio is larger than the reference value, the cooling power of the compressor is determined to be reduced to 1−n times of the predetermined cooling power,
wherein when the slope ratio is less than the reference value, the cooling power of the compressor is determined to be increased to 1+n times of the predetermined cooling power, and
wherein n is a value larger than 0 and is smaller than 1.

6. The method of claim 5 , wherein n is variable.

7. The method of claim 6 , wherein n is increased after an opening of a door is detected or after a defrosting operation of the refrigerator is performed.

8. A method for controlling a refrigerator, the refrigerator including a compressor configured to compress a refrigerant, a first evaporator configured to receive the refrigerant from the compressor to generate cold air for cooling a first storage compartment, a second evaporator configured to receive the refrigerant from the compressor to generate cold air for cooling a second storage compartment, a first valve configured to open or close a first refrigerant passage connected between the compressor and the first evaporator to allow the refrigerant to flow therebetween, and a second valve configured to open or close a second refrigerant passage connected between the compressor and the second evaporator to allow the refrigerant to flow therebetween, wherein the cooling of the first storage compartment and the cooling of the second compartment alternately operate, the method comprising:
performing a first cooling cycle for cooling the first storage compartment, such that the compressor is operated, the first valve is opened, and the second valve is closed;
determining that a stop condition of the first cooling cycle is satisfied; and
when the stop condition of the first cooling cycle is determined to be satisfied, closing the first valve and changing to a second cooling cycle for cooling the second storage compartment, such that the compressor is operated and the second valve is opened,
wherein the cooling power of the compressor in a next first cooling cycle is determined based on information from a previous first cooling cycle, wherein the cooling power for a cooling cycle is determined based on an on slope of the first storage compartment and an off slope of the first storage compartment, the on slope being a temperature change slope of the first storage compartment during an opening time of the first valve, and the off slope being a temperature change slope of the first storage compartment during a closing time of the first valve,
wherein the cooling power of the compressor in the next first cooling cycle is determined based on a comparison of a predetermined first reference value and a first slope ratio of the on slope of the first storage compartment and the off slope of the first storage compartment.

9. The method of claim 8 , wherein the cooling power of the compressor in a next second cooling cycle is determined based on information from a previous second cooling cycle, wherein the cooling power for a cooling cycle is determined based on an on slope of the second storage compartment and an off slope of the second storage compartment, the on slope being a temperature change slope of the second storage compartment during an opening time of the second valve, and the off slope being a temperature change slope of the second storage compartment during a closing time of the second valve.

10. The method of claim 9 ,
wherein the cooling power of the compressor in the next second cooling cycle is determined based on a comparison of a predetermined second reference value and a second slope ratio of the on slope of the second storage compartment and the off slope of the second storage compartment.

11. The method of claim 10 , wherein when the first slope ratio is equal to the first reference value, the cooling power of the compressor is determined to be maintained at the predetermined cooling power,
wherein when the first slope ratio is larger than the first reference value, the cooling power of the compressor is determined to be reduced to be less than the predetermined cooling power, and
wherein when the first slope ratio is less than the first reference value, the cooling power of the compressor is determined to be increased to be more than the predetermined cooling power.

12. The method of claim 10 , wherein when the second slope ratio is equal to the second reference value, the cooling power of the compressor is determined to be maintained at the predetermined cooling power,
wherein when the second slope ratio is larger than the second reference value, the cooling power of the compressor is determined to be reduced to be less than the predetermined cooling power, and
wherein when the second slope ratio is less than the second reference value, the cooling power of the compressor is determined to be increased to be more than the predetermined cooling power.

13. The method of claim 12 , wherein a first operation rate is a ratio of the opening time of the first valve to a sum of the opening time and the closing time of the first valve,
wherein the first operation rate is a predetermined operation rate, and
wherein the first ref

Assignees

• Lg Electronics Inc

Inventors

• Seong Giseok
• Nam Yoonseong
• Suh Yonghun
• Chung Myungjin

Classifications

• F25B49/022 Primary

  Compressor control arrangements · CPC title

• F25D29/00 Primary

  Arrangement or mounting of control or safety devices · CPC title

• F25B2600/0251

  with on-off operation · CPC title

• F25D17/067

  Evaporator fan units · CPC title

• F25D2700/12

  Sensors measuring the inside temperature · CPC title