Refrigerator cooling system and method for defrosting refrigerator

A refrigerator cooling system, comprising:

• a refrigerant circulation flow path including a compressor, a condenser and an evaporator;
• a defrosting branch;
• and
• a three-way valve,
• wherein:
• the evaporator comprises a heat exchange core tube,
• the heat exchange core tube comprises a main inlet and a main outlet in communication with the compressor,
• a middle section of the heat exchange core tube is provided with at least one middle inlet, wherein the heat exchange core tube is divided into at least two heat exchange sections including a first heat exchange section between the main inlet and the at least one middle inlet and a second heat exchange section between the main outlet and the at least one middle inlet,
• at least two temperature sensors each positioned on a corresponding heat exchange section of the at least two heat exchange sections of the heat exchange core, respectively, and configured to detect a temperature of the corresponding heat exchange section,
• a first flow path section of the refrigerant circulation flow path is positioned between an exhaust port of the compressor and the main inlet of the evaporator,
• the condenser is located on the first flow path section,
• the defrosting branch is connected among the exhaust port of the compressor, the main inlet, and the at least one middle inlet,
• the three-way valve is configured to switch the defrosting branch to communicate the exhaust port of the compressor with the main inlet or the at least one middle inlet, to enter a defrosting working mode based on a temperature detected by the at least two temperature sensors,
• the defrosting branch is configured to defrost the heat exchange core tube when the exhaust port of the compressor communicates with the main inlet, and the defrosting branch is configured to defrost the second heat exchange section when the exhaust port of the compressor communicates with the at least one middle inlet;
• and
• the three-way valve is further configured to switch the first flow path section to be in a circulating state, to enter a cooling working mode;
• the defrosting working mode comprises a full defrosting mode and a partial defrosting mode;
• wherein the refrigerator cooling system is configured to:
• obtain a first working parameter in response to the refrigerator cooling system being in the cooling working mode;
• and
• switch the refrigerator cooling system to enter the full defrosting mode or the partial defrosting mode according to the first working parameter:
• wherein the first working parameter comprises a temperature of a heat exchange section of the at least two heat exchange sections and a working duration T of the refrigerator.