Refrigerator and control method of refrigerator

Abstract

A refrigerator includes a storage compartment, an evaporator, a defrost heater provided around the evaporator, a compressor configured to compress a refrigerant discharged from the evaporator, and a fan configured to supply air cooled by the evaporator to the storage compartment. The refrigerator identifies an index value for detecting a defrost condition based on temperature information of the storage compartment and temperature information of the evaporator recorded at a first time point, and temperature information oaf the storage compartment and temperature information of the evaporator recorded at a second time point, and identifies whether the defrost condition is satisfied based on the index value, the operation information of the compressor, and the operation information of the fan; and operate the defrost heater based on identifying that the defrost condition is satisfied.

What is claimed is: 
     
         1 . A refrigerator comprising:
 a storage compartment;   an evaporator;   a defrost heater provided around the evaporator;   a compressor configured to compress a refrigerant discharged from the evaporator;   a fan configured to supply air cooled by the evaporator to the storage compartment;   at least one memory storing instructions and configured to record temperature information of the storage compartment, temperature information of the evaporator, operation information of the compressor, and operation information of the fan at defined time intervals; and   at least one processor,   wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to:
 identify an index value for detecting a defrost condition based on the temperature information of the storage compartment and the temperature information of the evaporator recorded at a first time point, and the temperature information of the storage compartment and the temperature information of the evaporator recorded at a second time point; 
 identify whether the defrost condition is satisfied based on the index value, the operation information of the compressor, and the operation information of the fan; and 
 operate the defrost heater based on identifying that the defrost condition is satisfied. 
   
     
     
         2 . The refrigerator of  claim 1 , wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to:
 identify a first value by assigning a defined first weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the first time point;   identify a second value by assigning a defined second weight to the difference value between the temperature value of the evaporator and the temperature value of the storage compartment recorded at the second time point; and   identify the index value based on the difference value between the first value and the second value.   
     
     
         3 . The refrigerator of  claim 1 , wherein the second time point is a past time point that satisfies a defined condition among time points before the first time point, and
 wherein the defined condition includes operation information of the compressor and operation information of the fan recorded at the past time point being identical to operation information of the compressor and operation information of the fan recorded at the first time point.   
     
     
         4 . The refrigerator of  claim 3 , wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to, based on a presence of a plurality of past time points that satisfy the defined condition, identify an oldest time point among the plurality of past time points as the second time point. 
     
     
         5 . The refrigerator of  claim 3 , wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to, based on an absence of a past time point that satisfies the defined condition, omit identifying the index value corresponding to the first time point. 
     
     
         6 . The refrigerator of  claim 1 , wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to delete oldest recorded information among the information recorded at the defined time intervals, based on a number of pieces of information recorded at the defined time intervals exceeding a defined number. 
     
     
         7 . The refrigerator of  claim 1 , wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to identify the index value at the defined time intervals, based on an elapse of a preset time from at least one of a time point at which an operation of the defrost heater ends or a time point at which power is applied to the refrigerator. 
     
     
         8 . The refrigerator of  claim 1 , wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to identify that the defrost condition is satisfied, based on the compressor being in operation for a preset time, a rotation speed of the fan being greater than a defined threshold rotation speed, and the index value corresponding to the first time point being greater than a threshold value. 
     
     
         9 . The refrigerator of  claim 1 , wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to identify that the defrost condition is satisfied, based on the compressor being in operation for a preset time, and a defined number of consecutive index values identified at the defined time intervals all being greater than a threshold value. 
     
     
         10 . The refrigerator of  claim 1 , wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to operate the defrost heater based on a cumulative operation time of the compressor exceeding a preset time, based on identifying that the defrost condition is not satisfied. 
     
     
         11 . A method for controlling a refrigerator comprising a storage compartment, an evaporator, a defrost heater provided around the evaporator, a compressor configured to compress a refrigerant discharged from the evaporator; and a fan configured to supply air cooled by the evaporator to the storage compartment, the method comprising:
 recording temperature information of the storage compartment, temperature information of the evaporator, operation information of the compressor, and operation information of the fan at defined time intervals;   identifying an index value for detecting a defrost condition based on the temperature information of the storage compartment and the temperature information of the evaporator recorded at a first time point, and the temperature information of the storage compartment and the temperature information of the evaporator recorded at a second time point;   identifying whether the defrost condition is satisfied based on the index value, the operation information of the compressor, and the operation information of the fan; and   operating the defrost heater based on identifying that the defrost condition is satisfied.   
     
     
         12 . The method of  claim 11 , wherein the identifying of the index value comprises:
 identifying a first value by assigning a defined first weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the first time point;   identifying a second value by assigning a defined second weight to the difference value between the temperature value of the evaporator and the temperature value of the storage compartment recorded at the second time point; and   identifying the index value based on the difference value between the first value and the second value.   
     
     
         13 . The method of  claim 11 , wherein the second time point is a past time point that satisfies a defined condition among time points before the first time point, and
 wherein the defined condition includes operation information of the compressor and operation information of the fan recorded at the past time point being identical to operation information of the compressor and operation information of the fan recorded at the first time point.   
     
     
         14 . The method of  claim 13 , further comprising:
 based on a presence of a plurality of past time points that satisfy the defined condition, identifying an oldest time point among the plurality of past time points as the second time point.   
     
     
         15 . The method of  claim 13 , further comprising:
 based on an absence of a past time point that satisfies the defined condition, omitting the identifying of the index value corresponding to the first time point.