Refrigerator and method for controlling the same

Abstract

A refrigerator may include: a storage compartment; a cooling sink (CS); a thermoelectric element including a cooling layer contacting the CS, the thermoelectric element configured to, based on a voltage pulse applied to the thermoelectric element, cool the cooling layer and thereby cool the CS; a fan controllable to generate an airflow to be cooled by the CS; a cooling duct covering the CS and fan, and configured to guide the airflow from the storage compartment to the CS and to accommodate defrost water generated by water, frozen by the CS, being defrosted; a temperature sensor to detect a temperature of the CS; and a processor configured to: control the cooling fan to evaporate the defrost water, and perform an anti-freezing control so that the defrost water does not freeze, the anti-freezing control including adjusting a duty ratio of the voltage pulse based on the detected temperature of the CS.

1 . A refrigerator, comprising:
 a storage compartment;   a cooling sink;   a thermoelectric element including a cooling layer in contact with the cooling sink, the thermoelectric element configured to, based on a voltage pulse applied to the thermoelectric element, cool the cooling layer and thereby cool the cooling sink;   a cooling fan controllable to generate a flow of air from the storage compartment to the cooling sink to be cooled by the cooling sink;   a cooling duct covering the cooling sink and the cooling fan, and configured to guide the flow of air from the storage compartment to the cooling sink and to accommodate defrost water generated by water, frozen by the cooling sink, being defrosted;   a temperature sensor configured to detect a temperature of the cooling sink; and   a processor configured to:
 control the cooling fan to evaporate the defrost water accommodated in the cooling duct, 
 perform an anti-freezing control so that the defrost water accommodated in the cooling duct does not freeze, the anti-freezing control including adjusting a duty ratio of the voltage pulse based on the temperature of the cooling sink detected by the temperature sensor. 
   
     
     
         2 . The refrigerator of  claim 1 , wherein the processor is further configured to determine the duty ratio based on the temperature of the cooling sink detected by the temperature sensor over a time interval so that the temperature of the cooling sink detected by the temperature sensor is maintained within a temperature range which prevents the defrost water accommodated in the cooling duct from freezing. 
     
     
         3 . The refrigerator of  claim 1 , wherein
 the processor is further configured to:
 reduce the duty ratio based on the temperature of the cooling sink detected by the temperature sensor being lower than or equal to a first threshold temperature; and 
 increase the duty ratio based on the temperature of the cooling sink detected by the temperature sensor being greater than or equal to a second threshold temperature that is greater than the first threshold temperature. 
   
     
     
         4 . The refrigerator of  claim 1 , wherein
 the processor is further configured to:
 maintain the duty ratio based on the temperature of the cooling sink detected by the temperature sensor being greater than a first threshold temperature and lower than a second threshold temperature, and 
 the first threshold temperature is lower than the second threshold temperature. 
   
     
     
         5 . The refrigerator of  claim 1 , wherein the processor is further configured to, based on a door of the refrigerator being opened for a threshold time, not apply the voltage pulse to the thermoelectric element and control the cooling fan to not generate the flow of air so that the defrost water accommodated in the cooling duct does not overflow the cooling duct. 
     
     
         6 . The refrigerator of  claim 1 , further comprising:
 an evaporator outside the storage compartment and configured to cool air to be supplied to the storage compartment; and   a compressor configured to supply a refrigerant to the evaporator,   wherein the processor is further configured to, based on refrigerant not being supplied to the evaporator by the compressor, not apply the voltage pulse to the thermoelectric element and control the cooling fan to not generate the flow of air.   
     
     
         7 . The refrigerator of  claim 1 , further comprising:
 an evaporator outside the storage compartment and configured to cool air to be supplied to the storage compartment; and   a return duct configured to guide air to be cooled from the storage compartment to the evaporator.   
     
     
         8 . The refrigerator of  claim 7 , further comprising:
 an evaporator fan configured to move air cooled by the evaporator to the storage compartment,   wherein the processor is further configured to temporarily control the cooling fan to not generate the flow of air so that moisture in the storage compartment is allowed to move to the evaporator through the return duct by operation of the evaporator fan, based on elapse of an evaporation time for evaporating the defrost water after the cooling fan is controlled to generate the flow of air.   
     
     
         9 . The refrigerator of  claim 1 , wherein the processor is further configured to temporarily stop the anti-freezing control based on a priority operation condition of the thermoelectric element being satisfied. 
     
     
         10 . A method for controlling a refrigerator including a storage compartment, a cooling sink, a thermoelectric element including a cooling layer in contact with the cooling sink, the thermoelectric element configured to, based on a voltage pulse applied to the thermoelectric element, cool the cooling layer and thereby cool the cooling sink, the refrigerator further including a cooling fan controllable to generate a flow of air from the storage compartment to the cooling sink to be cooled by the cooling sink, a cooling duct covering the cooling sink and the cooling fan, and configured to guide the flow of air from the storage compartment to the cooling sink and to accommodate defrost water generated by water, frozen by the cooling sink, being defrosted, a temperature sensor configured to detect a temperature of the cooling sink, and a processor, the method comprising:
 by the processor,   controlling the cooling fan to evaporate the defrost water accommodated in the cooling duct;   performing an anti-freezing control so that the defrost water accommodated in the cooling duct does not freeze, the anti-freezing control including adjusting a duty ratio of a voltage pulse based on the temperature of the cooling sink detected by the temperature sensor.   
     
     
         11 . The method of  claim 10 , wherein the performing of the anti-freezing control further includes, by the processor, determining the duty ratio based on the temperature of the cooling sink detected by the temperature sensor over a time interval so that the temperature of the cooling sink detected by the temperature sensor is maintained within a temperature range which prevents the defrost water accommodated in the cooling duct from freezing. 
     
     
         12 . The method of  claim 10 , wherein
 the performing of the anti-freezing control further includes:
 reducing the duty ratio based on the temperature of the cooling sink detected by the temperature sensor being lower than or equal to a first threshold temperature, and 
 increasing the duty ratio based on the temperature of the cooling sink detected by the temperature sensor being greater than or equal to a second threshold temperature that is greater than the first threshold temperature. 
   
     
     
         13 . The method of  claim 10 , wherein
 the performing of the anti-freezing control further includes:
 maintaining the duty ratio based on the temperature of the cooling sink detected by the temperature sensor being greater than a first threshold temperature and lower than a second threshold temperature, and 
 the first threshold temperature is lower than the second threshold temperature. 
   
     
     
         14 . The method of  claim 10 , further comprising:
 by the processor, based on a door of the refrigerator being opened for a threshold time, not applying the voltage pulse to the thermoelectric element and controlling the cooling fan to not generate the flow of air so that the defrost water accommodated in the cooling duct does not overflow the cooling duct.   
     
     
         15 . The method of  claim 10 , wherein
 the refrigerator includes:
 an evaporator outside the storage compartment and configured to cool air to be supplied to the storage compartment, and 
 a compressor configured to supply a refrigerant to the evaporator, and 
   the method further includes, by the processor, based on refrigerant not being supplied to the evaporator by the compressor, not applying the voltage pulse to the thermoelectric element, and controlling the cooling fan to not generate the flow of air.