Refrigerator

A refrigerator comprising:

• an evaporator configured to perform heat exchange;
• a defrost heater configured to operate to remove frost from the evaporator;
• a temperature sensor configured to detect an ambient temperature of the evaporator;
• and
• a controller configured to control the defrost heater,
• wherein, in response to a defrosting operation start time point arriving, the controller is configured to perform a defrost operation mode including a pre-defrost cooling mode, a heater operation mode, and post-defrost cooling mode, and
• perform a continuous operation mode in which the defrost heater is continuously turned on and a pulse operation mode in which the defrost heater is repeatedly turned on and off based on the heater operation mode, and
• in response to a cooling compartment door being opened during the continuous operation mode, turn off the defrost heater and supply predetermined level of cooling power in the post-defrost cooling mode,
• wherein the pre-defrost cooling mode includes:
• a first period in which cooling power of a first level is supplied,
• a second period in which cooling power of a second level higher than the first level is supplied,
• a third period in which cooling power is not supplied,
• a fourth period in which cooling power of the first level is supplied,
• wherein the fourth period is shorter than the first period, and the heater operation mode is performed after the fourth period,
• wherein the magnitude of the cooling power supplied in the post-defrost cooling mode is greater than the second level in the pre-defrost cooling mode.

A refrigerator comprising:

• an evaporator configured to perform heat exchange;
• a defrost heater configured to operate to remove frost from the evaporator;
• a temperature sensor configured to detect an ambient temperature of the evaporator;
• and
• a controller configured to control the defrost heater,
• wherein, in response to a defrosting operation start time point arriving, the controller is configured to perform a defrost operation mode including a pre-defrost cooling mode, a heater operation mode, and post-defrost cooling mode,
• perform a continuous operation mode in which the defrost heater is continuously turned on and a pulse operation mode in which the defrost heater is repeatedly turned on and off based on the heater operation mode, and
• change a magnitude of cooling power supplied in the post-defrost cooling mode based on an ON period of the defrost heater or a temperature of the cooling compartment in the pulse operation mode, and
• in response to the temperature of the cooling compartment in a previous defrost operation doing not reach a target temperature or in response to a defrost end temperature in the previous defrost operation being equal to or higher than a set temperature, the controller is configured to supply a predetermined level of cooling power in the post-defrost cooling mode,
• wherein the pre-defrost cooling mode includes:
• a first period in which cooling power of a first level is supplied,
• a second period in which cooling power of a second level higher than the first level is supplied,
• a third period in which cooling power is not supplied,
• a fourth period in which cooling power of the first level is supplied,
• wherein the fourth period is shorter than the first period, and the heater operation mode is performed after the fourth period,
• wherein the magnitude of the cooling power supplied in the post-defrost cooling mode is greater than the second level in the pre-defrost cooling mode.