AIR CONDITIONER AND METHOD OF CONTROLLING THE SAME

• US 20160131376A1
• Filed: 09/10/2015
• Published: 05/12/2016
• Est. Priority Date: 11/12/2014
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: YOON, Pilhyun, SA, Yongcheol, SONG, Chiwoo
• Granted Patent: US 10,443,872 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 11/41 Defrosting; Preventing freezing
• CPC Class Codes: F24F 11/42 of outdoor units
• CPC Class Codes: F24F 11/64 using pre-stored data
• CPC Class Codes: F24F 11/70 Control systems characterised by their outputs; Constructional details thereof
• CPC Class Codes: F24F 11/83 by controlling the supply of heat-exchange fluids to heat-exchangers
• CPC Class Codes: F24F 2110/00 Control inputs relating to air properties
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: F24F 2110/12 of the outside air
• CPC Class Codes: F24F 2110/20 Humidity
• CPC Class Codes: F24F 2110/22 of the outside air
• CPC Class Codes: F24F 2110/40 Pressure, e.g. wind pressure
• CPC Class Codes: F24F 2140/12 Heat-exchange fluid pressure
• CPC Class Codes: F25B 49/02 for compression type machines, plants or systems
• CPC Class Codes: F25B 49/022 Compressor control arrangements

Abstract

An air conditioner and a method of controlling the same are provided. The air conditioner includes an outside unit, which is provided with a compressor and an evaporator, an outside temperature sensor attached to the outside unit to sense outside temperature, an outside humidity recognition part attached to the outside unit to recognize information about outside humidity, a low pressure sensor that senses an evaporation pressure of the evaporator, and a control part that controls an operation of the compressor, based on both information about dew-point temperature sensed from the outside temperature sensor and the outside humidity recognition part and information about the evaporation pressure sensed from the low pressure sensor. The control part changes an operation frequency of the compressor according to whether the evaporation pressure is not lower than a preset reference low pressure, to prevent frosting of the evaporator.

Claims

1. An air conditioner comprising:

an outside unit having a compressor and an evaporator;

an outside temperature sensor attached to the outside unit to sense an outside temperature;

an outside humidity recognition part to recognize information about an outside humidity;

a low pressure sensor to sense an evaporation pressure of the evaporator; and

a control part to control an operation of the compressor based on information about dew-point temperature sensed from the outside temperature sensor and the outside humidity recognition part and based on information about the evaporation pressure sensed from the low pressure sensor,

wherein the control part changes an operation frequency of the compressor when the evaporation pressure is greater than or equal to a predetermined reference low pressure, to prevent frosting of the evaporator.

2. The air conditioner of claim 1, further comprising:

a memory part to store mapping information for changing the operation frequency of the compressor according to temperatures sensed by the outside temperature sensor, information about the outside humidity recognized by the outside humidity recognition part, and the evaporation pressure of the evaporator sensed by the low pressure sensor.

3. The air conditioner of claim 2, wherein the memory part stores information about the predetermined reference low pressure, and the predetermined reference low pressure comprises a first reference low pressure used to determine whether to start or stop a changing mode for the operation frequency of the compressor.

4. The air conditioner of claim 3, wherein the predetermined reference low pressure comprises a second reference low pressure used to determine whether to decrease the operation frequency of the compressor in the changing mode for the operation frequency of the compressor.

5. The air conditioner of claim 4, wherein when the evaporation pressure is less than the second reference low pressure, the control part controls the compressor such that the operation frequency of the compressor is decreased by a value corresponding to a first predetermined pressure.

6. The air conditioner of claim 4, wherein the predetermined reference low pressure comprises a third reference low pressure used to determine whether to increase the operation frequency of the compressor in the changing mode for the operation frequency of the compressor.

7. The air conditioner of claim 6, wherein when the evaporation pressure is greater than or equal to the second reference low pressure and is less than or equal to the third reference low pressure, the control part controls the compressor to maintain the operation frequency of the compressor.

8. The air conditioner of claim 6, wherein when the evaporation pressure is greater than the third reference low pressure and is less than the first reference low pressure, the control part controls the compressor to increase the operation frequency of the compressor.

9. The air conditioner of claim 3, wherein when the evaporation pressure is greater than or equal to the first reference low pressure, the control part stops the changing mode for the operation frequency of the compressor.

10. The air conditioner of claim 1, wherein the outside humidity recognition part comprises an outside humidity sensor attached to the outside unit.

11. The air conditioner of claim 2, wherein the memory part stores information obtained by mapping increase rate values of an operation frequency of the compressor according to the information about the outside humidity recognized by the outside humidity recognition part.

12. The air conditioner of claim 11, wherein when the outside humidity is less than a first predetermined outside humidity, the control part controls an increase rate of the operation frequency of the compressor to be maintained at a first predetermined operation frequency rate until the operation frequency is at a predetermined frequency after the compressor is activated;

wherein when it is recognized that the outside humidity is greater than a second predetermined outside humidity, the control part controls the increase rate to be maintained at a second predetermined operation frequency rate until the operation frequency is equal to the predetermined frequency after the compressor is activated,

whereby the second predetermined outside humidity is greater than the first predetermined outside humidity, and the first predetermined operation frequency rate is greater than the second predetermined operation frequency rate.

13. The air conditioner of claim 12, wherein when it is recognized that the outside humidity is greater than or equal to the first predetermined outside humidity and less than or equal to the second predetermined outside humidity, the control part controls the increase rate of the operation frequency to be decreased according to an increase of the outside humidity.

14. The air conditioner of claim 1, wherein the outside humidity recognition part comprises a communication part that receives the information about the outside humidity from a server.

15. A method of controlling an air conditioner, comprising:

inputting, by an operation command input part, an operation command for the air conditioner through which a refrigerating cycle circulates;

sensing, by an outside temperature sensor, an outside temperature;

sensing, by an outside humidity recognition part, an outside humidity;

sensing, by a low pressure sensor, a low pressure of the refrigerating cycle;

recognizing, by a main controller, information about the outside temperature, the outside humidity, and the low pressure of the refrigeration cycle;

determining, by the main controller, whether to perform a changing mode in which a target high pressure of the refrigerating cycle is changed, wherein the determination is made according to whether the low pressure of the refrigerating cycle is greater than a reference low pressure; and

changing, by the main controller, an operation frequency of a compressor of the air conditioner according to a range of the low pressure of the refrigerating cycle when the changing mode is performed.

16. The method of claim 15, further comprising:

performing, by the main controller, a normal mode in which the target high pressure of the refrigerating cycle of the compressor is maintained when it is recognized that the low pressure of the refrigerating cycle is greater than the reference low pressure; and

performing, by the main controller, the changing mode when it is recognized that the low pressure of the refrigerating cycle is less than the reference low pressure.

17. The method of claim 15, further comprising:

decreasing, by the main controller, the operation frequency of the compressor to decrease the target high pressure of the refrigerating cycle when the low pressure of the refrigerating cycle is less than a first reference low pressure,

wherein the first reference low pressure is less than the reference low pressure.

18. The method of claim 17, further comprising:

increasing, by the main controller, the operation frequency of the compressor to increase the target high pressure of the refrigerating cycle when the low pressure of the refrigerating cycle is greater than a second reference low pressure,

wherein the second reference low pressure is greater than the first reference low pressure.

19. The method of claim 15, further comprising:

controlling, by the main controller, the operation frequency of the compressor based on information mapped to decrease an increase rate of the operation frequency of the compressor as the outside humidity increases,

wherein the information mapped is stored in a memory part of the air conditioner.

20. The method of claim 19, wherein when it is recognized that the outside humidity is less than a first predetermined outside humidity, the increase rate of the operation frequency is controlled, by the main controller, to be maintained at a first predetermined operation frequency rate until the operation frequency is equal to a predetermined frequency after starting of the compressor;

when it is recognized that the outside humidity is greater than a second predetermined outside humidity, the increase rate of the operation frequency is controlled, by the controller, to be maintained at a second predetermined frequency rate until the operation frequency is equal to the predetermined frequency after the starting of the compressor; and

when it is recognized that the outside humidity is greater than or equal to the first predetermined outside humidity (and is less than or equal to the second predetermined outside humidity, the increase rate of the operation frequency is controlled, by the main controller, to be decreased according to the increase of the outside humidity.