KR20130050700A - Refrigerator using non-azeotropic refrigerant mixtures, and control method thereof - Google Patents

Abstract

PURPOSE: A refrigerator using a non-azeotropic refrigerant mixture refrigerant and a control method thereof are provided to reduce cycling loss by increasing a rotating speed of a compressor, by stopping a freezer compartment fan, by reducing a rotating speed of the freezer compartment fan compared to a freezing operating mode when simultaneously operating freezing and cooling in a non-azeotropic refrigerant mixture cycle. CONSTITUTION: A refrigerator comprises a compressor(16), a condenser(50), a cooling compartment evaporator(40), a freezer compartment evaporator(30), a freezer compartment fan(31), and a control unit. The compressor compresses a refrigerant. The condenser cools the refrigerant which is discharged from the compressor. The cooling compartment evaporator cools a cooling compartment. The freezer compartment evaporator is equipped in the upstream of the cooling compartment evaporator and between the condenser and the cooling compartment evaporator, and cools a freezer compartment. The freezer compartment fan blows cool air which is heat-exchanged in the freezer compartment evaporator. The control unit controls driving of the compressor and the freezer compartment fan.

Description

REFRIGERATOR USING NON-AZEOTROPIC REFRIGERANT MIXTURES, AND CONTROL METHOD THEREOF}

The present invention relates to a refrigerator using an azeotropic mixed refrigerant and a control method thereof.

Non-Azeotopic Refrigerant Mixture (NARM) is a refrigerant whose temperature changes during the phase change process, unlike pure refrigerants generally used in refrigerators.

The azeotropic mixed refrigerant may be applied to a refrigerant cycle to improve the efficiency of the refrigerator.

If an azeotropic mixed refrigerant is used, the refrigerant temperature at the point of evaporation is lower than the average evaporation temperature. If this is used for the operation of the freezer compartment, the average evaporation temperature can be increased compared to the pure refrigerant, thereby reducing the compression ratio. For this reason, the azeotropic mixed refrigerant cycle is configured to pass through the refrigerator compartment evaporator after the refrigerant passes through the freezer compartment evaporator, unlike a normal refrigerator.

This is a factor that increases the amount of refrigerant charge compared to the existing refrigerant cycle configuration in which the refrigerator compartment evaporator is installed upstream than the freezer compartment evaporator.

In the conventional refrigerant cycle configuration, the latent heat of evaporation is preferentially used in the refrigerator compartment evaporator and the remaining latent heat is used in the freezer compartment evaporator during simultaneous refrigeration / refrigeration operation. In this case, even if the latent heat of evaporation of the refrigerant available in the freezer compartment evaporator is insufficient, there is a freezer compartment operation mode.

However, such serial azeotropic mixed refrigerant cycle (Serial NARM Cycle) is inevitably installed upstream than the refrigerator compartment evaporator, so the latent latent heat used in the refrigerator compartment evaporator must be used in the refrigerator compartment evaporator. The refrigeration operation of the refrigerating compartment must be terminated in both refrigeration / refrigeration co-operation mode (since there is no refrigerating unit alone operation mode), so the latent heat of evaporation of the refrigerant remaining in the freezer evaporator must be large enough to cover the refrigerating compartment cooling operation.

These factors increase the amount of refrigerant charged in an azeotropic mixed refrigerant cycle. When the amount of refrigerant is increased, overcharging of the refrigerant occurs during refrigeration alone operation, resulting in a decrease in efficiency of the system. This is because the overfilling of refrigerant above the proper level causes the increase of compressor input and the increase of evaporation temperature by the increase of cycle operating pressure.

In addition, the increase in the amount of refrigerant charge serves to increase the loss caused by the on / off operation of the refrigerator. This loss is generally referred to as Cycling Loss and is inevitable in refrigerator systems that continuously perform on / off operation. However, the cycling losses tend to increase with increasing refrigerant charge. Cycling loss is the migration loss caused by the transfer of high-pressure refrigerant distributed on the high pressure side to the low pressure side when the compressor is turned off, and a portion of the refrigerant on the low-pressure side when the compressor is turned on to move to the high pressure side to restore stable cycle operation. It can be divided into Redistribution Loss, both of which increase as the refrigerant charge increases.

One aspect of the present invention is a refrigerator using an azeotropic mixed refrigerant that increases the latent heat of evaporation that can be utilized in a refrigerator compartment evaporator during simultaneous operation of freezer / refrigeration without increasing the refrigerant loading in an azeotropic mixed refrigerant cycle. Provide control method.

To this end, the refrigerator according to an aspect of the present invention includes a freezer compartment and a refrigerating compartment; A compressor for compressing the refrigerant; A condenser that receives and cools the refrigerant discharged from the compressor; A refrigerator compartment evaporator for cooling the refrigerator compartment; A freezer compartment evaporator provided between the condenser and the refrigerator compartment evaporator upstream than the refrigerator compartment evaporator and cooling the freezer compartment; A freezer compartment fan for blowing cold air heat-exchanged in the freezer compartment evaporator; And a control unit for controlling the operation of the compressor and the freezing compartment fan, wherein the control unit controls the rotational speed of at least one of the freezing compartment fan or the compressor to increase the amount of refrigerant flowing into the refrigerating compartment evaporator in the simultaneous operation of the freezing / freezing compartment. Variable control.

Here, the control unit may include reducing the rotational speed of the freezer compartment fan in the freezing / refrigerating simultaneous operation mode than in the freezing operation mode.

Here, the control unit may include temporarily reducing the rotational speed of the freezer compartment fan to zero in the freezing / refrigerating simultaneous operation mode.

Here, the control unit includes increasing the rotational speed of the compressor in the freezing / refrigeration simultaneous operation mode than in the freezing operation mode.

Herein, the control unit reduces the rotational speed of the freezer compartment fan in the freezing / freezing simultaneous operation mode than in the freezing operation mode or temporarily stops the freezer compartment fan and increases the rotational speed of the compressor than in the freezing operation mode. It includes.

According to another aspect of the present invention, there is provided a control method of a refrigerator, comprising: a control method of a refrigerator provided at an upstream side of a freezer compartment evaporator, the method comprising: determining whether a freezer / refrigeration simultaneous operation mode is performed; Variable speed control of at least one of a freezing compartment fan or a compressor to increase the amount of refrigerant flowing into the refrigerating compartment evaporator in the freezing / refrigerating simultaneous operation mode; It includes.

Here, the variable control includes reducing the rotational speed of the freezer compartment fan in the freezing / freezing simultaneous operation mode than in the freezing operation mode.

Here, the variable control includes temporarily reducing the rotational speed of the freezer compartment fan to zero in the freezing / refrigeration simultaneous operation mode.

Here, the variable control includes increasing the rotational speed of the compressor in the freezing / refrigeration simultaneous operation mode than in the freezing operation mode.

The variable control may reduce the rotational speed of the freezer compartment fan in the freezing / refrigerating simultaneous operation mode than in the freezing operation mode or temporarily stop the freezer compartment fan and reduce the rotational speed of the compressor in the freezing operation mode. It includes increasing.

According to an aspect of the present invention described above, in the non-azeotropic mixed refrigerant cycle (NARM Cycle) in the freezing / refrigeration simultaneous operation mode to reduce the rotational speed of the freezer fan compared to the freezing operation mode or to stop the freezer fan for a certain time or Or / and by increasing the rotational speed of the compressor, it is possible to reduce the latent heat of evaporation of the refrigerant consumed in the freezer compartment evaporator, so that the latent heat of evaporation that can be utilized in the refrigerator compartment evaporator can be relatively increased without increasing the amount of refrigerant charge. Not only can it prevent overcharge due to, but also reduce the cycling loss.

1 is a cross-sectional view of a refrigerator according to an embodiment of the present invention.
2 is a view showing a non-azeotropic mixed refrigerant cycle of the refrigerator according to an embodiment of the present invention.
3 is a control block diagram of a refrigerator according to one embodiment of the present invention.
Figure 4 is a timing diagram showing the rotational speed change of the freezer compartment during the freezing operation mode and the freezer / refrigeration operation mode of the refrigerator according to an embodiment of the present invention.
5 is a timing diagram illustrating a change in rotational speed of a compressor during a freezing operation mode and a simultaneous freezing / freezing operation mode of a refrigerator according to an embodiment of the present invention.
6 is a control flowchart of a control method of a refrigerator according to an embodiment of the present invention.
7 is a control flowchart of another control method of the refrigerator according to one embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a cross-sectional view of a refrigerator according to an embodiment of the present invention.

As illustrated in FIG. 1, the refrigerator includes a freezer compartment 12 located at an upper portion of the partition 11 forming a part of the main body 10 and an open front of the freezer compartment 12, and a freezer compartment door configured to open and close the front opening of the freezer compartment 12 ( 13), a refrigerating chamber 14 positioned below the partition 11 and having an open front, a refrigerating chamber door 15 for opening and closing the front opening of the refrigerating chamber 14, and a compressor provided at the lower rear portion of the main body 10 ( 16).

The freezer compartment heat exchanger (30, 31) and the refrigerator compartment heat exchanger (40, 41) are provided between the rear part and the main body of the freezer compartment (12) and the refrigerating compartment (14).

One side of the wall of the freezer compartment 12 and the refrigerating compartment 14 is provided with a freezer compartment temperature sensor 17 and a refrigerator compartment temperature sensor 18, respectively.

The freezer compartment 12 and the refrigerating compartment 14 are provided with a shelf 19 and a storage container 20 for storing food.

A machine room partitioned into a separate space is provided at the lower rear of the main body 10, and a compressor 16 is provided in the machine room. The compressor 16 is also provided with a condenser.

The freezer compartment heat exchanger (30, 31) is a freezer compartment evaporator (30) for cooling the air in the freezer compartment through heat exchange, and the cold air passing through the freezer compartment evaporator (30) installed above the freezer compartment evaporator (30). It includes a freezing compartment fan 31 for circulating inside.

A suction port 32 is formed at a lower portion of the freezer compartment evaporator 30 to suck air inside the refrigerator by driving the freezer compartment 31, and the cold air blown by the freezer compartment 31 at the rear side of the freezer compartment 12 is a freezer compartment. (12) A plurality of ejection openings 33 are formed for evenly discharging therein.

The refrigerator compartment heat exchanger (40, 41) is also similar to the freezer compartment heat exchanger (30, 31), the refrigerator compartment heat exchanger (40, 41) is a refrigerator compartment evaporator (40) for cooling the air in the refrigerator compartment (14) through heat exchange, The refrigerator compartment includes a refrigerator compartment fan 41 installed at an upper portion of the refrigerator compartment evaporator 40 to circulate the cold air that has passed through the refrigerator compartment evaporator 40 into the refrigerator compartment 14.

A suction flow passage 42 for sucking air inside the refrigerator is driven under the refrigerating chamber evaporator 40 by driving the refrigerating chamber fan 41, and cold air blown by the refrigerating chamber fan 41 is provided at the rear side of the refrigerating chamber 14. A plurality of discharge ports 43 are formed in the refrigerating chamber 14 to distribute the discharge evenly.

2 is a view showing a non-azeotropic mixed refrigerant cycle of the refrigerator according to an embodiment of the present invention.

As shown in FIG. 2, the azeotropic mixed refrigerant cycle of the refrigerator includes a compressor 16, a condenser 50, a capillary tube 60, a freezer compartment evaporator 30 and a refrigerator compartment evaporator 40, which are represented by solid lines. It is connected in order to the refrigerant flow path.

The capillary tube 60 is an example of an expansion device that expands the refrigerant discharged from the condenser 50 under reduced pressure.

In the vicinity of the condenser 50, a condenser fan 51 is provided which sucks the outside air to the condenser 50 side and discharges it to the outside so as to quickly exchange heat with the outside air of the refrigerator.

In addition, in the vicinity of the freezer compartment evaporator 30, a freezer compartment fan 31 is provided which sucks the internal air to the freezer compartment evaporator 30 side and discharges the interior air so as to quickly exchange heat with the freezer compartment air.

In the vicinity of the refrigerating chamber evaporator 40, a refrigerating chamber fan 41 is provided which sucks the internal air to the refrigerating chamber evaporator 40 side and discharges the internal air so as to quickly exchange heat with the refrigerating chamber internal air.

In addition, at the intersection of the refrigerant pipe connecting the freezer compartment evaporator 30 and the refrigerator compartment evaporator 40 and the refrigerant pipe connecting the suction side of the freezer compartment evaporator 30 and the compressor 16, a flow path for selectively switching each refrigerant passage. The three-way valve 70 which is a switching valve is provided.

The azeotropic mixed refrigerant cycle having the above-described configuration is made by circulating the azeotropic mixed refrigerant therein, as in the direction of the dotted arrow.

Non-azeotropic mixed refrigerants are refrigerants whose temperature changes during a phase change process, unlike pure refrigerants used in refrigerators. In other words, the temperature of the azeotropic mixed refrigerant increases while evaporating.

In general, the efficiency of the refrigerator cycle increases as the compression ratio between the high pressure side and the low pressure side decreases, which is limited by the refrigerant evaporation temperature of the freezer compartment evaporator. For example, if you want to keep the freezer temperature at -20 □, the evaporation temperature should be lower than this, so the internal temperature of the freezer compartment acts as a limit to reduce the compression ratio.

Under these conditions, when the azeotropic mixed refrigerant is used, the refrigerant temperature at the point of evaporation is lower than the average evaporation temperature. Therefore, when the refrigerant is used in the operation of the freezer, the average evaporation temperature can be increased compared to that of the pure refrigerant, thereby reducing the compression ratio. have.

For this reason, the azeotropic mixed refrigerant cycle is configured to pass through the refrigerator compartment evaporator 40 after the refrigerant passes through the freezer compartment evaporator 30, unlike the normal refrigerator.

Thus, in the azeotropic mixed refrigerant cycle, the freezer compartment evaporator 30 is located upstream of the refrigerator compartment evaporator 40.

Looking at the refrigerant flow in the azeotropic mixed refrigerant cycle, the refrigerant from compressor 16 reaches the three-way valve 70 via condenser 50, capillary 60 and freezer evaporator 30. At the three-way valve 70, the refrigerant pipe is branched. The refrigerant passing through the freezer compartment evaporator 30 in accordance with the change of the three-way valve 70 flows into the suction side of the compressor 16 through the refrigerator compartment evaporator 40, or the refrigerator compartment evaporator. It flows directly into the compressor (16) without passing through (40).

That is, by switching the three-way valve 70, the compressor 16, the condenser 50, the capillary tube 60, the freezer compartment evaporator 30, the freezer compartment evaporator 40, and the refrigerating / leading to the compressor 16 again A refrigeration cycle and a refrigerating cycle are formed leading to the compressor 16, the condenser 50, the capillary tube 60, the freezer compartment evaporator 30, and the compressor 16 again.

At this time, when the refrigerant passing through the freezer compartment evaporator 30 is to be introduced into the refrigerating compartment evaporator 40 side, the three-way valve 70 is turned on to open the refrigerant passage A of the three-way valve 70 and the refrigerant passage. (B) is closed. In addition, when the refrigerant passing through the freezer compartment evaporator 30 is introduced into the compressor 16 without passing through the refrigerating compartment evaporator 40, the three-way valve 70 is turned off so that the refrigerant flow path of the three-way valve 70 ( Close A) and open the refrigerant passage B.

In the freezer / refrigeration simultaneous operation mode, the gas refrigerant compressed at high temperature and high pressure in the compressor 16 of the refrigerator is introduced into the condenser 50. The condenser 50 releases heat to the outside by heat exchange with the outside air of the refrigerator introduced by the condenser fan 51 to convert the gas refrigerant into a liquid refrigerant. The liquid refrigerant passing through the condenser 52 is sequentially introduced into the freezer compartment evaporator 30 and the refrigerating compartment evaporator 40 while the pressure is reduced while passing through the capillary tube 60. The freezer compartment evaporator 30 absorbs heat inside the freezer compartment by heat exchange with air inside the refrigerator introduced by the freezer compartment 31 to convert the liquid refrigerant into a gas refrigerant. The cold cold air is generated by the phase change of the refrigerant, and the generated cold air is introduced into the room by the freezer compartment fan 31 to lower the freezer compartment temperature. In addition, the refrigerator compartment evaporator 40 absorbs heat in the refrigerator compartment by heat exchange with the air inside the refrigerator introduced by the refrigerator compartment fan 41, and the liquid refrigerant phase-converts to gas refrigerant. The cold air is generated by the phase change of the refrigerant, and the generated cold air is introduced into the room by the refrigerating chamber fan 41 to lower the refrigerating chamber temperature. The refrigerant passing through the refrigerator compartment evaporator 40 flows into the suction side of the compressor 16.

Meanwhile, the gas refrigerant compressed at high temperature and high pressure in the compressor 16 of the refrigerator in the freezing operation mode is introduced into the condenser 50. The condenser 50 releases heat to the outside by heat exchange with the outside air of the refrigerator introduced by the condenser fan 51 to convert the gas refrigerant into a liquid refrigerant. The liquid refrigerant passing through the condenser 52 is sequentially introduced into the freezer compartment evaporator 30 and the refrigerating compartment evaporator 40 while the pressure is reduced while passing through the capillary tube 60. The freezer compartment evaporator 30 absorbs heat inside the freezer compartment by heat exchange with air inside the refrigerator introduced by the freezer compartment 31 to convert the liquid refrigerant into a gas refrigerant. The cold cold air is generated by the phase change of the refrigerant, and the generated cold air is introduced into the room by the freezer compartment fan 31 to lower the freezer compartment temperature. The refrigerant passing through the freezer compartment evaporator 30 flows into the suction side of the compressor 16.

The refrigerator having the above-described configuration controls the amount of refrigerant to increase the amount of refrigerant flowing into the refrigerator compartment evaporator 40 to be higher than the reference refrigerant amount so as to relatively increase the latent heat of evaporation of the refrigerant that can be utilized in the refrigerator compartment evaporator 40 in the freezer / refrigeration simultaneous operation mode. Device 100.

3 is a control block diagram of a refrigerator according to one embodiment of the present invention. Figure 4 is a timing diagram showing the rotational speed change of the freezer compartment during the freezing operation mode and the freezer / refrigeration operation mode of the refrigerator according to an embodiment of the present invention. 5 is a timing diagram illustrating a change in rotational speed of a compressor during a freezing operation mode and a simultaneous freezing / freezing operation mode of a refrigerator according to an embodiment of the present invention.

As shown in FIG. 3, the refrigerant amount control apparatus 100 includes a program such as a freezing / freezing simultaneous operation mode and a freezing operation mode, and outputs control signals to each component to output the control signal to the freezing compartment 12 in the freezing / refrigeration simultaneous operation mode. ) And the refrigerating chamber 14 are simultaneously cooled, and in the freezing operation mode, the controller 110 controls to cool only the freezing chamber 12.

In particular, the control unit 110 decreases the latent heat of evaporation of the refrigerant consumed in the freezer compartment evaporator 30 in the freezer / refrigeration simultaneous operation mode to relatively increase the latent heat of evaporation of the refrigerant that can be utilized in the refrigerator compartment evaporator 40. To this end, the rotational speed of at least one of the freezer compartment fan 31 and / or the compressor 16 is variably controlled to increase the amount of the refrigerant flowing into the refrigerating chamber evaporator 40 in the freezing / refrigerating simultaneous operation mode than the reference refrigerant amount. Here, the reference refrigerant amount is the amount of refrigerant flowing into the refrigerator compartment evaporator 40 in the freezing operation mode.

The method of controlling the freezer compartment fan 31 may include a method of reducing the rotational speed of the freezer compartment fan 31 and a method of stopping the freezer compartment fan 31 for a predetermined time in a freezing / refrigerating simultaneous operation mode. All of these methods are to relatively increase the latent heat of evaporation available in the refrigerator compartment evaporator 40 by reducing the latent heat of evaporation of the refrigerant consumed in the freezer compartment evaporator 30. Through this, it is possible to perform the refrigerating compartment cooling operation with a smaller refrigerant loading amount.

 On the other hand, in addition to the method of controlling the freezer compartment fan 31, a method of controlling the rotational speed of the inverter compressor is also possible. This allows a similar effect to the method of controlling the freezer compartment fan 31 by increasing the compressor rotation speed compared to the refrigeration alone operation at the same time refrigeration / refrigeration operation. Increasing the rotational speed of the compressor 16 during the simultaneous refrigeration / refrigeration operation increases the mass flow rate of the refrigerant circulating in the cycle at the same refrigerant loading, so that the latent heat of evaporation of the refrigerant can be used in the refrigerator compartment evaporator.

An input side of the control unit 110 is electrically connected to the freezer compartment temperature sensor 17 for sensing the temperature of the freezer compartment 12 and the refrigerating compartment temperature sensor 14 for sensing the temperature of the refrigerating compartment 14.

In addition, a compressor 16, a freezer compartment fan 31, a refrigerating compartment fan 41, and a condenser fan 51, which are operated by a control signal of the controller 110, are electrically connected to an output side of the controller 110.

In addition, the control unit 110 includes a fan speed control circuit 111 for increasing or decreasing the rotational speed of the freezer compartment fan 31 and a compressor speed control circuit 112 for increasing or decreasing the rotational speed of the compressor 16.

On the other hand, the three-way valve 70 which is operated by the control signal of the control unit 110 is electrically connected to the output side of the control unit 110.

The control unit 110 performs any one of the freezing operation mode and the freezing / refrigeration operation mode. The controller 110 opens and closes each refrigerant flow path A and B through the three-way valve 70 in the freezing operation mode or the freezing / refrigerating operation mode to form a respective freezing cycle or a freezing / refrigerating cycle.

As shown in FIG. 4, the controller 110 rotates the rotational speed of the freezer compartment fan 31 to the reference speed N1 in the freezing operation mode, and the rotational speed of the freezer compartment fan 31 in the freezer / refrigeration simultaneous operation mode. Is reduced to the rotational speed N2, which is a rotational speed lower than this reference speed N1. Accordingly, the latent heat of evaporation of the refrigerant consumed in the freezer compartment evaporator 30 may be reduced in the simultaneous operation of the freezer / refrigerator operation so that the latent heat of evaporation of the refrigerant that may be utilized in the refrigerator compartment evaporator 40 may be relatively increased.

In addition, the controller 110 operates the freezer compartment fan 31 for a reference operation time in the freezing operation mode, and operates the freezer compartment fan 31 for an operation time shorter than the reference operation time in the freezer / refrigeration simultaneous operation mode. That is, the controller 110 controls the freezing compartment fan 31 to temporarily stop in the freezing / refrigeration simultaneous operation mode.

As shown in FIG. 5, the controller 110 rotates the rotational speed of the compressor 16 in the freezing operation mode to the reference speed N1, and adjusts the rotational speed of the compressor 16 in the freezing / refrigeration simultaneous operation mode. It increases to the rotation speed N2 which is a rotation speed higher than the reference speed N1. Accordingly, the latent heat of evaporation of the refrigerant that can be utilized in the refrigerating compartment evaporator 40 in the freezing / refrigeration simultaneous operation mode may be relatively increased.

6 is a control flowchart of a control method of a refrigerator according to an embodiment of the present invention.

Referring to FIG. 6, first, the controller 110 detects a temperature of the freezing compartment 12 and determines whether the freezing operation condition is satisfied by comparing with a set temperature (200).

If it is determined in the operation mode 200 that the freezing operation condition is satisfied, the controller 110 turns on the compressor 16 (202). At this time, the control unit 110 switches the refrigerant flow path such that the refrigerant passing through the freezer compartment evaporator 30 through the three-way valve 70 flows into the suction side of the compressor 16.

After the compressor 16 is turned on, the controller 110 rotates the freezer compartment fan 31 at a reference speed FS_r, which is a preset speed (204).

After rotating the freezer compartment fan 31, the controller 110 determines whether the freezing operation is off (206).

If the determination result of the operation mode 206 is the refrigeration operation off condition, the controller 110 turns off the compressor 16 (208) and turns off the freezer compartment fan 31 (210).

The controller 110 determines whether the refrigeration / refrigeration simultaneous operation condition is satisfied (212).

If it is determined in the operation mode 212 that the refrigeration / refrigeration simultaneous operating condition is satisfied, the controller 110 turns on the compressor 16 (214). At this time, the controller 110 switches the refrigerant flow path such that the refrigerant passing through the freezer compartment evaporator 30 through the three-way valve 70 flows into the suction side of the compressor 16 via the refrigerator compartment evaporator 40.

After the compressor 16 is turned on, the controller 110 rotates the freezer compartment fan 31 at a rotation speed FS <FS_r, which is lower than the reference speed FS_r, which is a preset speed (216).

On the other hand, if it is determined that the operation mode 200 does not satisfy the refrigeration operation condition, the controller 110 moves to the operation mode 212 and performs the following steps.

On the other hand, as a result of the determination of the operation mode 212, if the control unit 110 does not satisfy the refrigeration / refrigeration simultaneous operation conditions, and returns to the preset routine.

7 is a control flowchart of another control method of the refrigerator according to one embodiment of the present invention.

Referring to FIG. 7, first, the controller 110 detects a temperature of the freezing compartment 12 and determines whether the freezing operation condition is satisfied by comparing with the set temperature (300).

If it is determined in the operation mode 300 that the refrigeration operation condition is satisfied, the controller 110 rotates the compressor 16 at a preset reference speed CS_r (302). At this time, the control unit 110 switches the refrigerant flow path such that the refrigerant passing through the freezer compartment evaporator 30 through the three-way valve 70 flows into the suction side of the compressor 16.

After the compressor 16 is rotated at the reference speed CS_r which is a preset speed, the controller 110 rotates the freezer compartment fan 31 at the reference speed FS_r which is the preset speed (304).

After rotating the freezer compartment fan 31 at the reference speed CS_r, the controller 110 determines whether the freezing operation is off.

If the determination result of the operation mode 306 is the refrigeration operation off condition, the controller 110 turns off the compressor 16 (308), and turns off the freezer compartment fan 31 (310).

The controller 110 determines whether the refrigeration / refrigeration simultaneous operation condition is satisfied (312).

If it is determined in the operation mode 312 that the freezing / refrigerating simultaneous operation condition is satisfied, the controller 110 causes the compressor 16 to rotate at a speed higher than a preset reference speed CS_r. Rotate to (314). At this time, the controller 110 switches the refrigerant flow path such that the refrigerant passing through the freezer compartment evaporator 30 through the three-way valve 70 flows into the suction side of the compressor 16 via the refrigerator compartment evaporator 40.

After the compressor 16 is rotated at the rotational speed CS> CS_r, the controller 110 rotates the freezer compartment 31 at a reference speed FS_r, which is a preset speed, or a speed lower than this reference speed FS_r. Rotate to FS <FS_r) (316). At this time, the freezer compartment fan 41 is operated at the reference speed RS.

On the other hand, if it is determined that the operation mode 300, the control unit 110 does not satisfy the freezing operation conditions, the control unit 110 moves to the operation mode 312 and performs the following steps.

On the other hand, as a result of the determination of the operation mode 312, if the control unit 110 does not satisfy the refrigeration / refrigeration simultaneous operating conditions, and returns to the preset routine.

On the other hand, in order to maximize the application effect of the non-azeotropic mixed refrigerant, it is necessary to lower the dryness and the refrigerant temperature of the evaporator inlet may be equipped with a sub-cooler (sub-cooler) to achieve this. The sub cooler lowers the refrigerant dryness of the freezer compartment evaporator inlet (capillary tube outlet) through heat exchange between the outlet of the condenser 50 and the outlet side refrigerant pipe of the refrigerator compartment evaporator 40, thereby lowering the temperature of the freezer compartment evaporator inlet. The number and mounting position of this subcooler may vary depending on the nature of the cycle, but two subcoolers may be used, for example.

The sub cooler that performs heat exchange between the low pressure side pipe between the freezer compartment evaporator 30 and the refrigerator compartment evaporator 40 and the pipe of the condenser 50 is called a low temperature heat exchanger (LTHX), which is a refrigerant at the inlet of the evaporator. Along with lowering the temperature, it serves to increase the refrigerating compartment evaporation temperature. Since the operation of the refrigerating compartment uses a high dry portion of the latent heat of evaporation of the refrigerant, the refrigerating compartment evaporation temperature of the azeotropic mixed refrigerant is formed higher than that of the pure refrigerant. By using this, it is possible to reduce the thermodynamic irreversible loss by reducing the difference in heat exchange temperature between the refrigerant and the air. The irreversible loss decreases as the refrigerating chamber evaporation temperature increases, so the effect of the low temperature subcooler can be maximized.

 On the other hand, the sub-cooler that performs heat exchange between the evaporator outlet and the condenser pipe is called a high temperature heat exchanger (HTHX). This also serves to lower the evaporator inlet refrigerant temperature like the low temperature subcooler.

16: compressor 30: freezer evaporator
31: freezer compartment 40: refrigerator compartment evaporator
41: refrigerator compartment fan 50: condenser
51 condenser fan 60 capillary tube
70: 3-way valve

Claims (10)

Freezer and cold store rooms;
A compressor for compressing the refrigerant;
A condenser that receives and cools the refrigerant discharged from the compressor;
A refrigerator compartment evaporator for cooling the refrigerator compartment;
A freezer compartment evaporator provided between the condenser and the refrigerator compartment evaporator upstream than the refrigerator compartment evaporator and cooling the freezer compartment;
A freezer compartment fan for blowing cold air heat-exchanged in the freezer compartment evaporator;
It includes a control unit for controlling the drive of the compressor and the freezer compartment fan,
The control unit comprises a variable control of the rotational speed of at least one of the freezer compartment fan or the compressor to increase the amount of refrigerant flowing into the refrigerating compartment evaporator in the freezer / refrigerator simultaneous operation mode. The method of claim 1,
The control unit comprises a refrigerator to reduce the rotational speed of the freezer compartment fan in the freezer / refrigerator simultaneous operation mode than in the freezer operation mode. The method of claim 1,
The control unit comprises a refrigerator to temporarily reduce the rotational speed of the freezer compartment fan to zero in the freezer / refrigerator simultaneous operation mode. The method of claim 1,
And the control unit increases the rotation speed of the compressor in the freezing / refrigeration simultaneous operation mode than in the freezing operation mode. The method of claim 1,
The control unit may include reducing the rotational speed of the freezer compartment fan in the freezing / freezing simultaneous operation mode than in the freezing operation mode or temporarily stopping the freezer compartment fan and increasing the rotational speed of the compressor than in the freezing operation mode. Refrigerator. In the control method of the refrigerator provided with the freezer compartment evaporator upstream than the refrigerator compartment evaporator,
Determining whether the refrigerator / refrigeration simultaneous operation mode is selected;
Variable speed control of at least one of a freezing compartment fan or a compressor to increase the amount of refrigerant flowing into the refrigerating compartment evaporator in the freezing / refrigerating simultaneous operation mode; Control method of a refrigerator comprising a. The method according to claim 6,
The variable control may include reducing the rotational speed of the freezer compartment fan in the freezing / refrigerating simultaneous operation mode than in the freezing operation mode. The method according to claim 6,
The variable control, the control method of the refrigerator comprising the step of temporarily reducing the rotational speed of the freezer compartment fan to zero in the freezer / refrigerator simultaneous operation mode. The method according to claim 6,
The variable control is a control method of a refrigerator comprising increasing the rotational speed of the compressor in the freezing / refrigeration simultaneous operation mode than in the freezing operation mode. The method according to claim 6,
The variable control reduces the rotational speed of the freezer compartment fan in the freezing / freezing simultaneous operation mode than in the freezing operation mode or pauses the freezer compartment fan and increases the rotational speed of the compressor than in the freezing operation mode. Control method of a refrigerator comprising a.

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