WO2019128943A1

WO2019128943A1 - Refrigerator and defrosting control method therefor

Info

Publication number: WO2019128943A1
Application number: PCT/CN2018/123266
Authority: WO
Inventors: 苗建林; 李登强; 李春阳; 王铭
Original assignee: 青岛海尔股份有限公司; 青岛海尔特种制冷电器有限公司
Priority date: 2017-12-27
Filing date: 2018-12-24
Publication date: 2019-07-04
Also published as: CN108302880A; CN108302880B

Abstract

Disclosed are a refrigerator and a defrosting control method therefor. The refrigerator comprises: a refrigeration circulation system composed of a compressor (100), an evaporator (300) and a condenser (200); an electromagnetic defrosting device (400) comprising a plurality of defrosting modules arranged in a height direction of the evaporator (300); and a temperature detection device (310) and a power detection module (410). The method comprises: adjusting the power of a corresponding defrosting module based on variations in a surface temperature of the evaporator (300) and the position of each defrosting module, and if the surface temperature of the evaporator (300) exceeds a pre-set temperature, appropriately reducing the power of each defrosting module, and respectively reducing the power of the plurality of defrosting modules based on the different positions of the plurality of defrosting modules, so as to prevent an overly-quick temperature rise of the evaporator (300) from affecting subsequent refrigerator refrigeration.

Description

Refrigerator and defrosting control method thereof

Technical field

The invention relates to a refrigerating and freezing device, in particular to a refrigerator and a defrosting control method thereof.

Background technique

After the air-cooled refrigerator is running for a period of time, the evaporator will be frosted, and frosting will affect its operating efficiency. Therefore, the refrigerator needs to be defrosted after cooling for a period of time.

The existing refrigerator is provided with a defrosting heating wire near the evaporator. After the heating wire is energized, the evaporator is heated by heat radiation to achieve the purpose of defrosting. However, in the conventional electric heating defrosting, the temperature of the evaporator is higher near the position of the heating wire, the defrosting speed is fast, and the defrosting speed away from the heating wire is slow, so that the defrosting of the evaporator is easy to be uneven. In addition, the electric heating defrosting will simultaneously heat the air around the evaporator, which will not only cause thermal energy loss, but also prolong the defrosting time.

Moreover, the current defrosting method used in the refrigerator is to set a preset time according to the empirical data, and after the refrigerator is cooled for a certain period of time, the defrosting is automatically turned on, and the defrosting is stopped after a certain time of defrosting. However, this method of setting the defrost start point and the end point by experience is not effective because the frosting/defrosting condition cannot be clarified. Especially when it is determined that the defrosting is terminated, if the frosting on the evaporator is not completely eliminated, the defrosting is stopped, which may result in insufficient defrosting, thereby affecting the subsequent cooling effect of the evaporator; if frosting on the evaporator It has been completely eliminated, but the heating wire has not stopped heating, which will cause energy waste and affect the service life of the defrosting device.

Summary of the invention

In view of the above problems, the present invention has been made in order to provide a refrigerator and a defrosting control method thereof that overcome the above problems or at least partially solve the above problems.

An object of the present invention is to improve the defrosting effect of a refrigerator.

Another object of the invention is to prevent the evaporator temperature from becoming too high.

Another object of the invention is to ensure uniform defrosting of the evaporator.

In one aspect, the present invention provides a defrosting control method for a refrigerator, the refrigerator comprising an electromagnetic defrosting device for electromagnetically defrosting an evaporator of the refrigerator, the electromagnetic defrosting device comprising a plurality of arranging along the height direction of the evaporator The defrosting module, each defrosting module performs electromagnetic radiation defrosting to the corresponding evaporator section, and the method comprises: detecting that the refrigerator reaches the defrosting condition during the cooling operation of the refrigerator; and starting the electromagnetic defrosting device to start defrosting, each Each defrosting module operates at a preset initial power; continuously detects the surface temperature of the evaporator and the power of the defrosting module at the bottom; determines whether the surface temperature of the evaporator reaches a preset temperature; if so, according to the surface of the evaporator The temperature change and the position of each defrosting module respectively adjust the power of the plurality of defrosting modules; determine whether the power of the defrosting module located at the bottom reaches the target power; if so, turn off the electromagnetic defrosting device to end the defrosting.

Optionally, the step of separately adjusting the power of the plurality of defrost modules according to the surface temperature change of each evaporator section and the position of each defrost module comprises: calculating a temperature increment of the evaporator surface relative to the preset temperature; The power value of each defrosting module is respectively decreased according to the position of each defrosting module and the temperature increment of the evaporator; wherein the power reduction values of the plurality of defrosting modules are sequentially arranged according to the position of the defrosting module from high to low. The power of the reduced and bottommost defrosting module remains the same.

Optionally, before the step of detecting that the refrigerator reaches the defrosting condition, the method further includes: determining the target power when the refrigerator is powered on for the first time.

Optionally, when the refrigerator is powered on for the first time, the step of determining the target power comprises: detecting a surface temperature of the evaporator; determining whether the surface temperature of the evaporator reaches a preset temperature; if yes, turning on the electromagnetic defrosting device and continuing to run the first a preset time period; during the continuous operation of the electromagnetic defrosting device, calculating the average power of the bottommost defrosting module in the last second preset time period as the target power.

Optionally, the step of detecting that the refrigerator reaches the defrosting condition comprises: recording a continuous running time of the refrigerator and a cumulative opening time of the door body of the refrigerator during the continuous running time; determining whether the continuous running time of the refrigerator reaches a preset cumulative running time, and The cumulative number of opening of the door exceeds the preset number; if so, it is determined that the refrigerator reaches the defrosting condition.

In another aspect, the present invention provides a refrigerator comprising: a refrigeration cycle system comprising a compressor, an evaporator and a condenser; an electromagnetic defrosting device disposed toward the evaporator and configured to be heated by radiating electromagnetic waves to the evaporator An evaporator for defrosting the evaporator; comprising a plurality of defrosting modules arranged along the height direction of the evaporator, each defrosting module performing electromagnetic radiant defrosting to the corresponding evaporator section; and a temperature detecting device disposed at The evaporator surface is configured to detect the surface temperature of the evaporator; the power detection module is connected to the bottommost defrosting module and configured to detect the operating power of the bottommost defrosting module; wherein the electromagnetic defrosting device is configured to be cooled in the refrigerator During the operation, when the refrigerator is detected to reach the defrosting condition, the defrosting is started; during the defrosting process, the defrosting modules are respectively adjusted according to the surface temperature change of the evaporator and the position of each defrosting module. Power; and is also configured to reach a preset temperature at the surface temperature of the evaporator, and the power of the bottommost defroster module reaches the target power Closing the case, the end of the defrost.

Optionally, the electromagnetic defrosting device further comprises: a power adjustment module configured to calculate a temperature increment of the evaporator surface relative to the preset temperature; respectively reducing each of the defrosting module positions and the evaporator temperature increments The power value of the defrosting module.

Optionally, the power detection module is further configured to determine the target power when the refrigerator is powered on for the first time.

Optionally, the electromagnetic defrosting device is further configured to open and continue to operate for a first preset time period when the surface temperature of the evaporator reaches a preset temperature when the refrigerator is first powered on; the power detection module is further configured During the continuous operation of the electromagnetic defrosting device, the average power of the bottommost defrosting module in the last second predetermined time period is calculated as the target power.

Optionally, the refrigerator further includes: a running time detecting device configured to record a continuous running time of the refrigerator; and a door opening and closing detecting device disposed on the door body or the box of the refrigerator, configured to be in a continuous running time of the refrigerator The number of times the door body is opened is recorded; wherein the electromagnetic defrosting device is configured to be turned on when the continuous running time of the refrigerator reaches a preset cumulative running time, and the cumulative opening number of the door body exceeds a preset number of times.

The present invention provides a refrigerator. The refrigerator of the invention defrosses the evaporator by using an electromagnetic defrosting device, and the electromagnetic defrosting device heats the evaporator by using the principle of magnetic field induced eddy current heating, and the defrosting effect is compared with the heating wire used in the prior art. Better. Specifically, the electromagnetic defrosting device can uniformly emit electromagnetic radiation to various portions of the evaporator, so that the entire evaporator can be uniformly heated, and the defrosting of each part of the evaporator is more uniform. Moreover, since only metal can accept electromagnetic waves and convert magnetic energy into heat, the electromagnetic defrosting device only heats the surface of the evaporator without heating the air around the evaporator. Therefore, the defrosting of the refrigerator of the present embodiment is more direct and rapid, and at the same time, heating of the position other than the frosting is avoided, and the heat utilization efficiency is improved.

Further, the present invention also provides a defrosting control method. The method adjusts the power of the corresponding defrost module based on changes in the surface temperature of the evaporator and the position of each defrost module. When the surface temperature of the evaporator exceeds 0 ° C, the power of each defrosting module is appropriately reduced to prevent the evaporator temperature from rising too fast, which affects the subsequent refrigerator cooling. Since the degree of frosting of the evaporators at different positions is different, in the present invention, the power of the plurality of defrosting modules is respectively reduced according to different positions of the plurality of defrosting modules. Specifically, according to the frosting characteristics of the surface of the evaporator: the evaporator portion at the top portion has a lower degree of frost formation, and the evaporator portion at the bottom portion has a lower degree of frost formation. In the present invention, the defrosting module at the top portion is mainly lowered. The power value is such that the evaporator is more evenly defrosted.

The above as well as other objects, advantages and features of the present invention will become apparent to those skilled in the <

DRAWINGS

Some specific embodiments of the present invention are described in detail below by way of example, and not limitation. The same reference numbers in the drawings identify the same or similar parts. Those skilled in the art should understand that the drawings are not necessarily drawn to scale. In the figure:

1 is a schematic view of an evaporator and an electromagnetic defrosting device of a refrigerator according to an embodiment of the present invention;

2 is a schematic block diagram of a refrigerator in accordance with one embodiment of the present invention;

3 is a schematic diagram of a defrosting control method of a refrigerator according to an embodiment of the present invention;

4 is a flow chart of a defrosting control method of a refrigerator in accordance with one embodiment of the present invention.

Detailed ways

As shown in FIG. 1 and FIG. 2, an embodiment of the present invention first provides a refrigerator 1. In this embodiment, the refrigerator is an air-cooled refrigerator, and the air-cooled refrigerator includes a door body, a box body, and a refrigeration cycle system composed of the compressor 100, the evaporator 300, and the condenser 200. The interior of the cabinet forms a storage compartment and a supply duct at the rear of the storage compartment. The evaporator 300 is disposed in the air supply duct. In the embodiment, the outer casing of the evaporator 300 is made of a metal material, and the interior thereof is formed. The refrigerant flows through the pipes and cools the air inside the ducts through the refrigerant flowing inside. A fan is disposed inside the air supply duct, and the fan is used to transport dry and cool air cooled by the evaporator 300 in the air duct to the storage room to cool the storage room. The air entering the storage room will circulate again into the air duct. The interior of the air-cooled refrigerator is cooled by the above-described air flow circulation principle.

The refrigerator of this embodiment further includes an electromagnetic defrosting device 400. The electromagnetic defrosting device 400 is disposed in the air duct and disposed toward the evaporator 300. In the present embodiment, the electromagnetic defrosting device 400 is disposed at the back of the evaporator 300, and is configured to heat the evaporator 300 by radiating electromagnetic waves to the evaporator 300 to defrost the evaporator 300. The electromagnetic defrosting device 400 heats the evaporator 300 by using a magnetic field induced eddy current heating principle, and is internally provided with an electromagnetic coil, and uses a current to generate a magnetic field through the coil. When the magnetic force in the magnetic field passes through the evaporator 300, it is evaporated. The surface of the casing 300 generates a myriad of small eddy currents, causing the metal ions in the casing of the evaporator 300 to move at a high speed, and the temperature of the evaporator 300 rises rapidly. The electromagnetic defrosting device 400 converts magnetic energy by electric energy, and the magnetic energy converts heat energy to quickly heat the evaporator 300 itself, and the evaporator 300 directly melts the frost after heating.

In the present embodiment, the electromagnetic defrosting device 400 includes three defrosting modules arranged along the height direction of the evaporator 300, that is, a first defrosting module 401 located at the top, a second defrosting module 402 located at the middle, and located at the most The third defrosting module 403 at the bottom. Each defrosting module can operate independently and perform electromagnetic radiant defrosting to the corresponding evaporator section, that is, the first defrosting module 401 defrosts the top of the evaporator 300; the second defrosting module 402 aligns the evaporator The middle portion of the 300 is defrosted; the third defrosting module 403 defroses the bottom of the evaporator 300. The operating power of each defrosting module can be independently adjusted.

The refrigerator of the present embodiment defrosses the evaporator 300 by the electromagnetic defrosting device 400, and the defrosting effect is better by using the heating wire for defrosting compared with the prior art. Specifically, the electromagnetic defrosting device 400 can uniformly emit electromagnetic radiation to various portions of the evaporator 300, and the evaporator 300 as a whole can uniformly heat up, so that the defrosting of each portion of the evaporator 300 is more uniform. Moreover, since only metal can receive electromagnetic waves and convert magnetic energy into heat, the electromagnetic defrosting device 400 only heats the surface of the evaporator 300 without heating the air around the evaporator 300. Therefore, the defrosting of the refrigerator of the present embodiment is more direct and rapid, and at the same time, heating of the position other than the frosting is avoided, and the heat utilization efficiency is improved.

The electromagnetic defrosting device 400 is provided with a power adjustment module 404. The power adjustment module 404 can change the operating power of each defrosting module in the electromagnetic defrosting device 400 by adjusting the voltage or current across the electromagnetic defrosting device 400. Different working environments. In addition, the operating power of each defrosting module also adjusts its own power according to the degree of frost on the surface of the evaporator 300 (that is, the surface temperature and the thickness of the frosting). When the surface temperature of the evaporator 300 gradually increases, When the frosting is reduced, the working power of the defrosting module will increase slightly.

The refrigerator of this embodiment further includes: a temperature detecting device 310 and a power detecting module 410. The temperature detecting device 310 is disposed on the surface of the evaporator 300 and configured to detect the surface temperature of the evaporator 300. In this embodiment, the temperature detecting device 310 can be a temperature sensor. The temperature sensor is electrically connected to the electromagnetic defrosting device 400, and the electromagnetic defrosting device 400 is capable of receiving temperature data detected by the temperature sensor.

The power detection module 410 is electrically connected to the electromagnetic defrosting device 400 and configured to detect the operating power of the third defrosting module 403. In the present embodiment, the power detecting module 410 calculates the instantaneous power of the third defrosting module 403 by detecting the voltage across the electromagnetic defrosting device 400 and the current through the electromagnetic defrosting device 400.

The electromagnetic defrosting device 400 is configured to be turned on in the case of detecting that the refrigerator reaches the defrosting condition during the cooling operation of the refrigerator to start defrosting; and is further configured to reach a preset temperature at the surface temperature of the evaporator 300, and third When the power of the defrosting module 403 reaches the target power, the defrosting is ended.

The above preset temperature is 0 ° C, that is, the freezing point temperature. When the temperature of the evaporator 300 reaches 0 ° C, the frosting of the surface evaporator 300 has been substantially eliminated. In the present embodiment, in order to more accurately determine whether the frost is completely removed, the power detecting module 410 further detects the power of the defrosting module at the bottom of the electromagnetic defrosting device 400, that is, the power value of the third defrosting module 403. According to the foregoing description, in the case that the power adjustment module 404 does not actively adjust the operating power of the defrosting module, the operating power of the defrosting module will also change passively according to the degree of frosting of the evaporator 300, that is, the working of the defrosting module. There is a certain correspondence between power and frosting. When the frost on the surface of the evaporator 300 is completely cleaned, the defrosting module reaches a certain power. The above target power is the power of the third defrosting module 403 when the surface temperature of the evaporator 300 is 0 ° C and the evaporator 300 is not frosted. Therefore, when the third defrosting module 403 rises to the target power, it indicates that the frost on the surface of the evaporator 300 has been removed. In the present embodiment, the surface temperature of the evaporator 300 and the operating power of the defrosting module are combined to determine the defrosting end time point, and it is possible to more accurately determine when the defrosting is ended. The defrosting of the evaporator 300 is prevented from being insufficient, which affects the subsequent cooling of the evaporator 300.

The power detection module 410 is also configured to determine the target power when the refrigerator is first powered on. The electromagnetic defrosting device 400 is further configured to open and continue to operate for a first predetermined period of time when the surface temperature of the evaporator 300 reaches a preset temperature when the refrigerator is first powered on. The power detection module 410 also calculates the average power of the third defrosting module 403 during the last second predetermined period of time as the target power during the continuous operation of the electromagnetic defrosting device 400. In this embodiment, the preset temperature is 0 ° C, the first preset time period is 30 s, and the second preset time period is 5 s. When the refrigerator is first powered on, as the cooling process continues, the temperature of the evaporator 300 will gradually decrease from above 0 °C. When the temperature of the evaporator 300 is lowered to 0 ° C, the surface thereof begins to frost, at which time the electromagnetic defrosting device 400 is turned on, and the electromagnetic defrosting device 400 is controlled to continue to operate for 30 s. When the electromagnetic defrosting device 400 is just turned on, its power value may fluctuate somewhat, and after the power of the electromagnetic defrosting device 400 tends to be stable, its power value is recorded. Specifically, the power detection module 410 detects an average power value within 30 seconds of the third defrosting module 403 running for the last 5 seconds. The average power value is the power value corresponding to the third defrosting module 403 when the surface of the evaporator 300 is 0 ° C and there is no frost, that is, the target power.

The electromagnetic defrosting device 400 is further configured to adjust the power of the plurality of defrosting modules according to a change in surface temperature of the evaporator 300 and a position of each of the defrosting modules during defrosting. When the surface temperature of the evaporator 300 exceeds 0 ° C, the power of each defrosting module is appropriately lowered to prevent the temperature of the evaporator 300 from rising too fast, which affects the subsequent refrigerator cooling. Since the degree of frosting of the evaporator 300 at different positions is different, in the present embodiment, the electromagnetic defrosting device 400 first calculates the temperature increase of the evaporator surface with respect to the preset temperature; and according to each of the defrosting modules The location and the temperature increment of the evaporator 300 respectively reduce the power value of each defrosting module.

The refrigerator further includes a running time detecting device 520 and a door opening and closing detecting device 510. The runtime detecting means 520 is configured to record the continuous running time of the refrigerator. In this embodiment, the running time detecting device 520 may be a timing device disposed on the main control board of the refrigerator. The door opening and closing detecting device 510 is disposed on the door body or the cabinet of the refrigerator, and is configured to record the number of opening of the door body during the continuous operation of the refrigerator. In the present embodiment, the door opening and closing detecting device 510 includes a pressure sensor disposed on the door body or the casing and a counter, and the pressure sensor determines whether the door body is opened by sensing the pressure on the door body or the casing, and the counter Accumulate the number of opening times of the door.

The electromagnetic defrosting device 400 is configured to be turned on when the continuous running time of the refrigerator reaches a preset cumulative running time, and the cumulative opening number of the door exceeds a preset number of times. In general, the degree of frost on the surface of the evaporator 300 is related to the cumulative running time of the refrigerator and the cumulative number of open doors of the refrigerator. The longer the running time of the refrigerator, the lower the temperature of the evaporator 300, the easier it is to frost. At the same time, each time the user opens the door, the moisture of the external environment of the refrigerator enters the air duct, and it is easy to form frost on the surface of the evaporator 300. The more the cumulative opening of the door body, the more easily the evaporator 300 is frosted. In this embodiment, when the refrigerator accumulates the cooling operation for M hours and the number of door opening times reaches N times, it is determined that the refrigerator reaches the defrosting condition, and the electromagnetic defrosting device 400 turns on the defrosting. The above M and N can be set according to the specific model of the refrigerator.

The compressor 100 is also configured to close before the electromagnetic defrosting device 400 is turned on to suspend refrigeration of the refrigerator. The compressor 100 is turned off to stop cooling before the refrigerator is ready to start defrosting. After the refrigerator is stopped for a period of time and the temperature of the evaporator 300 is slightly increased, the defrosting process is further entered to prevent the evaporator 300 from suddenly rising in temperature, causing damage to the evaporator 300.

The invention also provides a refrigerator defrosting control method, and FIG. 3 is a schematic diagram of a refrigerator defrosting control method according to an embodiment of the invention, the method generally comprising the following steps:

In step S302, during the cooling operation of the refrigerator, it is detected that the refrigerator reaches the defrosting condition. After the air-cooled refrigerator runs for a period of time, the evaporator 300 may have a frosting condition, which affects its operating efficiency. Therefore, the refrigerator needs to perform a defrosting operation on the evaporator 300 after a certain period of cooling. In the embodiment of the present invention, the defrosting condition may be that the surface temperature of the evaporator 300 is lowered to a certain extent, or the number of opening of the refrigerator door body reaches a certain number of times. In other embodiments of the invention, the defrosting condition may also be that the surface of the evaporator 300 is frosted to a certain thickness.

Step S304, the electromagnetic defrosting device is turned on to start defrosting, and each defrosting module operates at a preset initial power. When the refrigerator reaches the defrosting condition, it indicates that the refrigerator needs to be defrosted, and at this time, the electromagnetic defrosting device 400 is turned on to start the defrosting process. At the beginning of the defrosting, all the defrosting modules are operated according to a preset initial power. In the present embodiment, the initial power can be set to 500w.

Step S306, continuously detecting the surface temperature of the evaporator and the power of the defrosting module located at the bottom. The electromagnetic defrosting device 400 is turned on to start defrosting, and continuously detects the surface temperature of the evaporator 300 of the refrigerator and the power of the defrosting module at the bottom of the electromagnetic defrosting device 400. During the defrosting process, the surface temperature of the evaporator 300 of the refrigerator and the power of the third defrosting module 403 are detected in real time, and according to the numerical values of the above two data, whether to reduce the power of the three defrosting modules and the end of the defrosting Time point.

In step S308, it is determined whether the surface temperature of the evaporator 300 reaches a preset temperature. In this embodiment, the preset temperature is 0 ° C, that is, the freezing point temperature.

Step S310, if the result of the determination in step S308 is YES, the power of the corresponding defrost module is adjusted according to the change of the surface temperature of the evaporator and the position of each defrost module. When the surface temperature of the evaporator 300 exceeds 0 ° C, the power of each defrosting module is appropriately lowered to prevent the evaporator temperature from rising too fast, which affects the subsequent refrigerator cooling. Since the degree of frosting of the evaporator 300 at different positions is different, in the embodiment, the power of the plurality of defrosting modules can be respectively reduced according to different positions of the plurality of defrosting modules.

In step S312, it is determined that the power at the bottommost defrosting module reaches the target power. In the present embodiment, in order to more accurately determine whether the frosting is completely removed, the power detecting module 410 further detects the power of the electromagnetic defrosting device 400 at the bottommost defrosting module. According to the foregoing description, the operating power of the defrosting module changes according to the degree of frosting of the evaporator 300, that is, the working power of the defrosting module has a certain correspondence with the degree of frosting, and the target power represents the surface temperature of the evaporator 300. The power of the bottommost defrosting module (ie, the third defrosting module 403) is 0 ° C and the evaporator 300 is free of frost. As the defrosting process progresses, the power at the bottommost defrosting module gradually increases, and when the defrosting module rises to the target power, it indicates that the frost on the surface of the evaporator 300 has completely been removed. In the present embodiment, the surface temperature of the evaporator 300 and the operating power of the defrosting module are combined to determine the defrosting end time point, and it is possible to more accurately determine when the defrosting is ended. The defrosting of the evaporator 300 is prevented from being insufficient, which affects the subsequent cooling of the evaporator 300. Further, by providing the target power, it is possible to prevent the power of the electromagnetic defrosting device 400 from being excessively large, and it is possible to protect the electromagnetic defrosting device 400 and improve the service life of the electromagnetic defrosting device 400.

In step S314, if the decision result in the step S312 is YES, the electromagnetic defrosting device 400 is turned off to end the defrosting. When the surface temperature of the evaporator 300 reaches 0 ° C and the power of the bottom defrosting module reaches the target power, the defrosting process of the refrigerator evaporator 300 is ended, and after waiting for a certain period of time, the refrigerator re-opens the compressor 100 for cooling.

4 is a flow chart of a method for controlling defrosting of a refrigerator according to an embodiment of the present invention, which performs the following steps in sequence:

In step S402, the surface temperature of the evaporator 300 is continuously detected when the refrigerator is powered on for the first time. When the refrigerator is first powered on, as the cooling process continues, the temperature of the evaporator 300 will gradually decrease from above 0 °C.

In step S404, it is determined whether the surface temperature of the evaporator 300 reaches a preset temperature. In this embodiment, the preset temperature is 0 °C.

In step S406, if the result of the determination in step S404 is YES, the electromagnetic defrosting device 400 is turned on and continues to operate for 30 s. When the temperature of the evaporator 300 is lowered to 0 ° C, the surface thereof begins to frost, at which time the electromagnetic defrosting device 400 is turned on, and the electromagnetic defrosting device 400 is controlled to continue to operate for 30 s.

Step S408, during the continuous operation of the electromagnetic defrosting device 400, calculate the average power in the last 5s of the third defrosting module 403 as the target power. When the electromagnetic defrosting device 400 is turned on, its power value may fluctuate somewhat. After the power of the electromagnetic defrosting device 400 tends to be stable, the power value of the third defrosting module 403 is recorded. Specifically, the power detection module 410 detects the average power value of the third defrosting module 403 within 30 seconds of the operation of the electromagnetic defrosting device 400. The average power value is the power value corresponding to the third defrosting module 403 when the surface of the evaporator 300 is 0 ° C and there is no frost.

In step S410, the continuous running time of the refrigerator and the cumulative opening times of the door body of the refrigerator during the continuous running time are recorded.

Step S412, determining whether the continuous running time of the refrigerator reaches a preset cumulative running time, and the cumulative opening time of the door body exceeds a preset number of times. In general, the degree of frost on the surface of the evaporator 300 is related to the cumulative running time of the refrigerator and the cumulative number of open doors of the refrigerator. The longer the running time of the refrigerator, the lower the temperature of the evaporator 300, the easier it is to frost. At the same time, each time the user opens the door, the moisture of the external environment of the refrigerator enters the air duct, and it is easy to form frost on the surface of the evaporator 300. The more the cumulative opening of the door body, the more easily the evaporator 300 is frosted. When the accumulated running time of the refrigerator and the number of times the door body is opened exceeds a certain level, the refrigerator starts the defrosting process.

In step S414, if the result of the determination in step S412 is YES, the electromagnetic defrosting device 400 is turned on to start defrosting, and the surface temperature of the evaporator 300 of the refrigerator and the power of the electromagnetic defrosting device 400 are continuously detected. In the present embodiment, when the refrigerator accumulates the cooling operation for M hours and the number of door opening times reaches N times, it is determined that the refrigerator reaches the defrosting condition, and the electromagnetic defrosting device 400 turns on the defrosting. The above M and N are set according to the specific conditions of the refrigerator.

In step S416, it is determined that the surface temperature of the evaporator 300 reaches a preset temperature. In this embodiment, the preset temperature can be set to 0 °C. When the evaporator temperature surface reaches 0 ° C, the frost on the surface of the evaporator has been substantially removed. When the evaporator temperature surface reaches 0 ° C, the power of each defrosting module is appropriately lowered to prevent the evaporator temperature from rising too fast.

Step S418, if the result of the determination in step S416 is YES, calculate the temperature increment of the evaporator surface with respect to the preset temperature.

Step S420, respectively reducing the power value of each defrosting module according to the position of each defrosting module and the temperature increment of the evaporator. In this embodiment, each time the surface of the evaporator 100 is raised by 1 ° C, the power conditioning module 404 controls the power of each defrosting module to decrease by a certain value. Since the degree of frost at the bottom of the evaporator is greater than the degree of frost at the top, the power conditioning module 404 primarily reduces the power value of the defrosting module located at the top. That is to say, the power reduction values of the plurality of defrosting modules are sequentially decreased in order from the top to the bottom of the defrosting module, so that the evaporator 300 is uniformly defrosted. In this embodiment, the power reduction value of the third defrosting module 403 is the largest, and the second defrosting module 402 is second, and the power reduction value of the first defrosting module 401 is the smallest. Specifically, the first defrosting module 401 reduces the power by 30w every time the evaporator 300 is raised by 1 ° C; the second defrosting module 402 reduces the power by 15 w for each 1 ° C increase of the evaporator 300; The third defrosting module 403 does not reduce its own power as the temperature of the evaporator 300 increases, that is, the third defrosting module 403 maintains the initial power. The method of the embodiment can continue high-power defrosting on the bottom of the evaporator 300 with a high degree of frosting, and at the same time slow down the defrosting speed of the top of the evaporator with a low degree of frosting, thereby making the evaporator 300 uniform and evenly defrosted. There is no frost residue at the bottom of the evaporator, and the temperature at the top of the evaporator is prevented from rising too high. Further, in the present embodiment, the above temperature increase has an upper limit value, and when the surface temperature of the evaporator 300 exceeds 5 ° C, the power of all the defrosting modules does not decrease as the temperature of the evaporator 300 rises.

Step S422, determining whether the power of the third defrosting module 403 reaches the target power. The power of the electromagnetic defrosting device 400 is continuously monitored to determine the point in time at which the defrosting is terminated.

In step S424, if the result of the determination in step S422 is YES, the electromagnetic defrosting device 400 is turned off, and the defrosting is ended.

In this regard, it will be appreciated by those skilled in the <RTIgt;the</RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; The content directly determines or derives many other variations or modifications consistent with the principles of the invention. Therefore, the scope of the invention should be understood and construed as covering all such other modifications or modifications.

Claims

A defrosting control method for a refrigerator, the refrigerator comprising an electromagnetic defrosting device for electromagnetically defrosting an evaporator of the refrigerator, the electromagnetic defrosting device comprising a plurality of arranging along the height direction of the evaporator a defrosting module, each defrosting module performing electromagnetic radiation defrosting to the corresponding evaporator section, the method comprising:

During the cooling operation of the refrigerator, detecting that the refrigerator reaches a defrosting condition;

Turning on the electromagnetic defrosting device to start defrosting, and each of the defrosting modules operates at a preset initial power;

Continuously detecting the surface temperature of the evaporator and the power of the defrosting module at the bottom;

Determining whether the surface temperature of the evaporator reaches a preset temperature;

If yes, adjusting the power of the plurality of defrosting modules according to a change in surface temperature of the evaporator and a position of each of the defrosting modules;

Determining whether the power of the defrosting module located at the bottom reaches the target power;

If so, the electromagnetic defrosting device is turned off to end the defrosting.
The defrosting control method according to claim 1, wherein the step of separately adjusting the power of the plurality of defrosting modules according to a change in surface temperature of each of the evaporator sections and a position of each of the defrosting modules includes :

Calculating a temperature increase of the evaporator surface relative to the preset temperature;

Decreasing the power value of each defrosting module according to the position of each of the defrosting modules and the temperature increment of the evaporator; wherein

The power reduction values of the plurality of defrosting modules are sequentially decreased according to the position of the defrosting module from high to low, and the power of the defrosting module at the bottom remains unchanged.
The defrosting control method according to claim 1, wherein before the step of detecting that the refrigerator reaches the defrosting condition, the method further comprises:

The target power is determined when the refrigerator is first powered on.
The defrosting control method according to claim 2, wherein when the refrigerator is powered on for the first time, the step of determining the target power comprises:

Detecting a surface temperature of the evaporator;

Determining whether the surface temperature of the evaporator reaches the preset temperature;

If yes, turning on the electromagnetic defrosting device and continuously running for a first preset time period;

During the continuous operation of the electromagnetic defrosting device, the average power of the defrosting module at the bottom of the last second predetermined time period is calculated as the target power.
The defrosting control method according to claim 1, wherein the step of detecting that the refrigerator reaches a defrosting condition comprises:

Recording the continuous running time of the refrigerator and the cumulative opening times of the door body of the refrigerator during the continuous running time;

Determining whether the continuous running time of the refrigerator reaches a preset cumulative running time, and the cumulative opening times of the door body exceeds a preset number of times;

If so, it is determined that the refrigerator reaches the defrosting condition.
A refrigerator comprising:

a refrigeration cycle system consisting of a compressor, an evaporator and a condenser;

An electromagnetic defrosting device disposed toward the evaporator, configured to heat the evaporator by radiating electromagnetic waves to the evaporator to defrost the evaporator; comprising a plurality of rows arranged along a height direction of the evaporator a defrosting module, wherein each defrosting module performs electromagnetic radiation defrosting to the corresponding evaporator section;

a temperature detecting device disposed on the surface of the evaporator and configured to detect a surface temperature of the evaporator;

a power detection module, connected to the bottommost defrosting module, configured to detect the operating power of the defrosting module at the bottom;

The electromagnetic defrosting device is configured to be turned on when the refrigerator is detected to reach a defrosting condition during the cooling operation of the refrigerator to start defrosting; in the defrosting process, according to the surface of the evaporator The temperature change and the position of each of the defrost modules respectively adjust the power of the plurality of defrost modules; and are further configured to reach a preset temperature at a surface temperature of the evaporator, and the bottommost defrost module The power is turned off when the target power reaches the target power, and the defrosting is ended.
The refrigerator according to claim 6, wherein the electromagnetic defrosting device further comprises:

a power adjustment module configured to calculate a temperature increment of the evaporator surface relative to the preset temperature; respectively reducing a power of each defrosting module according to a position of each of the defrosting module and a temperature increment of the evaporator value.
A refrigerator according to claim 6, wherein

The power detection module is further configured to determine the target power when the refrigerator is powered on for the first time.
A refrigerator according to claim 7, wherein

The electromagnetic defrosting device is further configured to open and continue to operate for a first preset time period when the surface temperature of the evaporator reaches the preset temperature when the refrigerator is first powered on;

The power detection module is further configured to calculate, during the continuous operation of the electromagnetic defrosting device, an average power of the defrosting module at the bottom of the last second predetermined time period as the target power.
The refrigerator according to claim 6, further comprising:

a runtime detecting device configured to record a continuous running time of the refrigerator; and

a door opening and closing detecting device is disposed on the door body or the box of the refrigerator, and configured to record the number of times the door body is opened during the continuous operation of the refrigerator;

The electromagnetic defrosting device is configured to be turned on when the continuous running time of the refrigerator reaches a preset cumulative running time, and the cumulative opening number of the door body exceeds a preset number of times.