US20070033954A1

US20070033954A1 - Driving controlling apparatus for air conditioner having plural compressors and method thereof

Info

Publication number: US20070033954A1
Application number: US11/462,517
Authority: US
Inventors: Ji-Young Jang; Chan-Ho Song; Jae-Hoon Sim; Se-Yoon Oh
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2005-08-10
Filing date: 2006-08-04
Publication date: 2007-02-15
Also published as: CN100538194C; JP2007046895A; KR100700545B1; KR20070018640A; CN1912487A; CA2555432A1

Abstract

A driving controlling apparatus for an air conditioner having a plurality of compressors, and a method thereof. The apparatus comprises a flow amount distribution resistor installed at an outlet of an expansion valve, for passing a certain amount of refrigerant; and a controlling unit for detecting a current load and outputting a control signal so as to introduce a certain amount of refrigerant into the flow amount distribution resistor based on a driving mode corresponding to the detected load.

Description

RELATED APPLICATION

The present disclosure relates to subject matter contained in priority Korean Application No. 10-2005-0073499, filed on Aug. 10, 2005, which is herein expressly incorporated by reference in its entirely.

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to a driving controlling apparatus for an air conditioner having a plurality of compressors, and a method thereof, and more particularly, to a driving controlling apparatus for an air conditioner having a is plurality of compressors capable of preventing increase of consumption power and decrease of a driving efficiency of a system due to an excessive refrigerant flow, and a method thereof.
2. Description of the Background Art
Generally, an air conditioner serves to lower an indoor temperature by using a refrigerating cycle of a refrigerant compressed into a high temperature and a high pressure by a compressor.
When the air conditioner is provided two compressors, the two compressors are selectively driven according to a refrigerating load.
FIG. 1 is a view showing a construction of an air conditioner having two compressors in accordance with the related art.
As shown, the related art air conditioner comprises a first compressor 10 and a second compressor 20 selectively driven for varying a compression amount of a refrigerant; a condenser 1 for condensing a refrigerant compressed by the first compressor 10 and the second compressor 20; an expansion valve 2 for expanding a refrigerant condensed by the condenser 1; and an evaporator 3 for heat-exchanging a refrigerant expanded by the expansion valve 2 with indoor air.
It is assumed that the first compressor 10 is an inverter-type small capacity compressor and the second compressor 20 is a constant speed-type large capacity compressor.
Suction pipes 11 and 21 of the first compressor 10 and the second compressor 20 are connected to hoses 31 and 32 diverged from a suction hose 30, respectively. Also, discharge pipes 12 and 22 of the first compressor 10 and the second compressor 20 are connected to hoses 41 and 42 diverged from a discharge hose 40, respectively.
Suction valves 33 and 34 and the discharge valves 43 and 44 selectively opened and closed by manually or by a controlling unit (not shown) such as a microcomputer are connected to the diverged hoses 31, 32, 41, and 42, respectively.
The air conditioner having two compressors performs a refrigerating operation by selectively driving the first compressor 10 and the second compressor 20 according to a refrigerating load.
More concretely, when the refrigerating load is small, only the first compressor 10 is driven. When the refrigerating load is medium, only the second compressor 20 is driven. On the contrary, when the refrigerating load is large, both the first compressor 10 and the second compressor 20 are driven thereby to vary a compression amount of a refrigerant required for a cooling operation.
When a refrigerant is compressed by the first compressor 10 or the second compressor 20 so as to perform a refrigerating cycle, lubricant inside the first compressor 10 and the second compressor 20 is mixed with the refrigerant thus to be discharged. The discharged lubricant performs a refrigerating cycle, and then is re-sucked into the first compressor 10 and the second compressor 20 via an accumulator (not shown).
Herein, a refrigerant amount to be introduced into the compressor is set on the basis of a compressor having a capacity of 100% for a constant cooling capability.
However, when the system is driven in a minimum capacity driving mode (driving of only one compressor), the refrigerant amount to be introduced into the compressor having a capacity of 100% increases a consumption power due to an excessive refrigerant amount thereby to lower a driving efficiency of the system.
Furthermore, under a state that the air conditioner having a plurality of compressors is driven in an over-load driving mode, when a temperature of a refrigerant discharged from the compressor is increased more than a certain degree, the capacity of the compressors is decreased or the compressors are turned off thereby to maintain a reliability of the system.
When the compressors are frequently turned off, an indoor comfortable degree is lowered.
That is, when a temperature of a refrigerant discharged from the compressors is increased more than a certain degree, the compressors are frequently turned off. Accordingly, cool air is not constantly supplied indoors thereby to cause the indoor comfortable degree to be lowered.

SUMMARY OF THE INVENTION

Therefore, an object of the present invention is to provide a driving controlling apparatus for an air conditioner having a plurality of compressors capable of preventing increase of consumption power and decrease of a driving efficiency of a system due to an excessive refrigerant amount even if the compressors of the air conditioner having a maximum refrigerant amount are driven in a minimum capacity driving mode, in which a refrigerant cooled by an expansion is partially heat-exchanged by a condensing unit thus to lower a condensation temperature, and a method thereof.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a driving controlling apparatus for an air conditioner having a plurality of compressors, comprising: a flow amount distribution resistor installed at an outlet of an expansion valve, for passing a certain amount of refrigerant; and a controlling unit for detecting a current load and outputting a control signal so as to introduce a certain amount of refrigerant into the flow amount distribution resistor based on a driving mode corresponding to the detected load.
According to another aspect of the present invention, there is provided a driving controlling apparatus for an air conditioner having a plurality of compressors, comprising: a flow amount distribution resistor installed at an outlet of an expansion valve, for passing a certain amount of refrigerant; a switching unit installed at an outlet of the flow amount distribution and switched by a control signal, for controlling a flow of a refrigerant discharged from the flow amount distribution resistor; a condenser heat exchanging unit for lowering a temperature of a condenser by using a refrigerant introduced through the switching unit, and introducing the refrigerant into an accumulator; and a controlling unit for detecting a current load, selecting a driving mode based on the detected load thereby driving the system, and outputting a control signal so as to control the switching unit based on the selected driving mode.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is also provided a driving controlling method for an air conditioner having a plurality of compressors, comprising: detecting a current load and selecting a compressor driving capacity based on the detected load; and analyzing the compressor driving capacity, and lowering a temperature of a condenser by using a certain amount of refrigerant based on the analyzed result.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.
In the drawings:
FIG. 1 is a view showing a construction of an air conditioner having two compressors in accordance with the related art;
FIG. 2 is a block diagram showing a driving controlling apparatus for an air conditioner having a plurality of compressors according to the present invention;
FIG. 3 is a flowchart showing a driving controlling method for an air conditioner having a plurality of compressors according to the present invention;
FIG. 4 is a schematic view showing a condenser and a heat exchanging unit of FIG. 2 by a double tube heat exchanging method; and
FIG. 5 is a schematic view showing the condenser and the heat exchanging unit of FIG. 2 by a capillary tube heat exchanging method.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.
Hereinafter, a driving controlling apparatus for an air conditioner having a plurality of compressors capable of preventing increase of consumption power and decrease of a driving efficiency of a system due to an excessive refrigerant flow even if the compressors of the air conditioner having a maximum refrigerant amount are driven in a minimum capacity driving mode, and a method thereof.
FIG. 2 is a block diagram showing a driving controlling apparatus for an air conditioner having a plurality of compressors according to the present invention.
As shown in FIG. 2, a driving controlling apparatus for an air conditioner having a plurality of compressors according to the present invention comprises: a switching unit 100; a condenser heat exchanging unit 200; a controlling unit 300; and a flow amount distribution resistor 400.
The flow amount distribution resistor 400 is installed at a flow path diverged from refrigerant path positioned at an outlet of an expansion valve, and passes a certain amount of refrigerant.
The flow amount distribution resistor 400 has a preset resistance value for passing an optimum amount of refrigerant obtained by an experiment.
The switching unit 100 is installed at an outlet of the flow amount distribution resistor 400 and is switched by a control signal, thereby controlling a flow of a refrigerant discharged from the flow amount resistor 400.
The condenser heat exchanging unit 200 lowers a temperature of a condenser by using a refrigerant introduced through the switching unit 100, and introduces the refrigerant to an accumulator.
As shown in FIG. 4, the condenser heat exchanging unit 200 lowers a temperature of the condenser by a double tube heat exchanging method shown in FIG. 4. As shown in FIG. 5, the condenser heat exchanging unit 200 lowers a temperature of the condenser by a capillary tube heat exchanging method shown in FIG. 5.
The controlling unit 300 detects a current load, and selects a driving mode based on the detected load thus to drive the system. Then, the controlling unit 300 outputs a control signal for controlling the switching unit 100 based on the selected driving mode.
More concretely, when the compressors are driven in a maximum capacity driving mode, the controlling unit 300 turns off the switching unit 100 so that a refrigerant can be prevented from flowing to the condenser heat exchanging unit 200, and then introduces a refrigerant outputted from an expansion valve into an evaporator.
On the contrary, when the compressors are in a minimum capacity driving mode, the controlling unit 300 turns on the switching unit 100 so that a refrigerant discharged from the expansion valve can be partially introduced to the condenser heat exchanging unit 200 via the flow amount distribution resistor 400.
The operation of the driving controlling apparatus for an air conditioner having a plurality of compressors will be explained with reference to FIG. 3.
First, the controlling unit 300 detects a current driving load (SP1), and selects a compressor driving capacity based on the detected load (SP2).
When a current driving load is judged to be a normal load, the controlling unit 300 selects a maximum capacity driving mode. On the contrary, when a current driving load is judged to be a low load, the controlling unit 300 selects a minimum capacity driving mode.
For instance, when the compressors are driven in a maximum capacity driving mode, two compressors are simultaneously driven. On the contrary, when the compressors are driven in a minimum capacity driving mode, only one compressor, mainly one compressor having a smaller capacity is driven.
Then, the controlling unit 300 analyzes the selected driving mode (SP3), and controls a refrigerant amount based on the analyzed result (SP4). Next, the controlling unit 300 turns on the switching unit 100 so as to prevent a temperature of a refrigerant discharged from the compressor from being increased (SP6).
More concretely, when the compressors are driven in a maximum capacity driving mode, the controlling unit 300 turns off the switching unit 100 so as to completely use introduced refrigerants, thereby completely introducing the refrigerant discharged from the expansion valve into the evaporator (SP5).
On the contrary, when the compressors are driven in a minimum capacity driving mode, the controlling unit 300 turns on the switching unit 100 so that the refrigerant discharged from the expansion valve can be partially introduced to the condenser heat exchanging unit 200 via the flow amount distribution resistor 400. Accordingly, a temperature of the condenser is lowered, and the system is driven with the rest refrigerant (SP6).
As the result, when the compressors are driven in a minimum capacity driving mode, the system is driven with an optimum refrigerant thereby to reduce a consumption power.
When the system is driven in an over-load state (where a driving load is higher than a normal load), the controlling unit 300 turns on the switching unit 100 in the same manner as the operation in the minimum capacity driving mode thereby to lower the temperature of the condenser. Accordingly, a temperature of a refrigerant discharged from the compressor is lowered, thereby preventing an OFF state of the compressor due to a temperature rise of the refrigerant discharged from the compressor.
The over-load driving mode is set by a user. For instance, the over-load driving mode is set when a user's preset temperature is different from an indoor temperature by more than a certain degree, or an outdoor temperature is higher than a certain degree.
That is, in the present invention, a refrigerant amount is distributed in a minimum capacity driving mode or an over-load driving mode except a normal driving mode.
In the driving controlling apparatus for an air conditioner having a plurality of compressors according to the present invention, a refrigerant cooled by an expansion is partially heat-exchanged by the condenser, thereby having a lowered condensation temperature. Accordingly, even if the air conditioner having a maximum refrigerant amount is driven in a minimum capacity driving mode, a consumption power increase and a driving efficiency decrease of the system due to an excessive refrigerant flow are prevented.
Furthermore, in the present invention, when the system is driven under an sover-load state, a refrigerant cooled by an expansion is partially heat-exchanged by the condenser, thereby having a lowered condensation temperature. Accordingly, a temperature of the refrigerant discharged from the compressor is prevented from being increased more than a certain degree, thereby enhancing a reliability of the system.
As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims.

Claims

1. A driving controlling apparatus for an air conditioner having a plurality of compressors, comprising:

a flow amount distribution resistor installed at an outlet of an expansion valve, for passing a certain amount of refrigerant; and

a controlling unit for detecting a current load and outputting a control signal so as to introduce a certain amount of refrigerant into the flow amount distribution resistor based on a driving mode corresponding to the detected load.

2. The apparatus of claim 1, wherein the flow amount distribution resistor is installed at a flow path diverged from a refrigerant path positioned at the outlet of the expansion valve.

3. The apparatus of claim 1, further comprising a switching unit installed at the outlet of the flow amount distribution resistor and switched by a control signal, for controlling a flow of a refrigerant discharged from the flow amount distribution resistor.

4. The apparatus of claim 1, further comprising a condenser heat exchanging unit for lowering a temperature of a condenser by using a refrigerant introduced through the switching unit, and introducing the refrigerant into an accumulator.

5. The apparatus of claim 1, wherein when the compressors are driven in a maximum capacity driving mode, the controlling unit turns off the switching unit so as to shield a refrigerant flow to the condenser heat exchanging unit, and thereby introduces a refrigerant discharged from the expansion valve to an evaporator.

6. The apparatus of claim 1, wherein when the compressors are driven in a minimum capacity driving mode (or an over-load driving mode), the controlling unit turns on the switching unit thereby to partially introduce a refrigerant discharged from the expansion valve to the condenser heat exchanging unit via the flow amount distribution resistor.

7. The apparatus of claim 1, wherein the flow amount distribution resistor has a preset resistance value for passing an optimum refrigerant.

8. The apparatus of claim 4, wherein the condenser heat exchanging unit lowers a temperature of the condenser by a double tube heat exchanging method.

9. The apparatus of claim 4, wherein the condenser heat exchanging unit lowers a temperature of the condenser by a capillary tube heat exchanging method.

10. A driving controlling apparatus for an air conditioner having a plurality of compressors, comprising:

a flow amount distribution resistor installed at an outlet of an expansion valve, for passing a certain amount of refrigerant;

a switching unit installed at an outlet of the flow amount distribution and switched by a control signal, for controlling a flow of a refrigerant discharged from the flow amount distribution resistor;

a condenser heat exchanging unit for lowering a temperature of a condenser by using a refrigerant introduced through the switching unit, and introducing the refrigerant into an accumulator; and

a controlling unit for detecting a current load, selecting a compressor driving capacity based on the detected load, and outputting a control signal so as to control the switching unit based on the selected driving mode.

11. The apparatus of claim 10, wherein the flow amount distribution resistor is installed at a flow path diverged from a refrigerant path positioned at the outlet of the expansion valve.

12. The apparatus of claim 10, wherein when the compressors are driven in a maximum capacity driving mode, the controlling unit turns off the switching unit so as to shield a refrigerant flow to the condenser heat exchanging unit, and thereby introduces a refrigerant discharged from the expansion valve to an evaporator.

13. The apparatus of claim 1, wherein when the compressors are driven in a minimum capacity driving mode (or an over-load driving mode), the controlling unit turns on the switching unit thereby to partially introduce a refrigerant discharged from the expansion valve to the condenser heat exchanging unit via the flow amount distribution resistor.

14. The apparatus of claim 10, wherein the flow amount distribution resistor has a preset resistance value for passing an optimum refrigerant.

15. The apparatus of claim 10, wherein the condenser heat exchanging unit lowers a temperature of the condenser by a double tube heat exchanging method.

16. The apparatus of claim 10, wherein the condenser heat exchanging unit lowers a temperature of the condenser by a capillary tube heat exchanging method.

17. A driving controlling method for an air conditioner having a plurality of compressors, comprising:

detecting a current load and selecting a compressor driving capacity based on the detected load; and

analyzing the compressor driving capacity, and lowering a temperature of a condenser by using a certain amount of refrigerant based on the analyzed result.

18. The method of claim 17, wherein the step of lowering a temperature of a condenser comprises introducing a refrigerant discharged from the expansion valve into an evaporator when the compressors are driven in a maximum capacity driving mode.

19. The method of claim 17, wherein the step of lowering a temperature of a condenser comprises partially introducing a refrigerant discharged from the expansion valve into the condenser heat exchanging unit via the flow amount distribution resistor when the compressors are driven in a minimum capacity driving mode.

20. The method of claim 17, wherein the step of lowering a temperature of a condenser comprises lowering a temperature of the condenser by the condenser heat exchanging unit with a capillary tube heat exchanging method.

21. The method of claim 17, wherein the step of lowering a temperature of a condenser comprises lowering a temperature of the condenser by the condenser heat exchanging unit with a double tube heat exchanging method.