Refrigerator refrigerating system, refrigerator and refrigerating method

The invention provides a refrigerator refrigerating system, a refrigerator and a refrigerating method, relates to the technical field of refrigerating equipment, and solves the technical problems that in the prior art, the storage temperature of frozen food in a refrigerator is mostly below-20 DEG C, the evaporation pressure is low, the indoor temperature is high (the indoor heating temperature is high in winter), the condensing pressure is high, and the refrigerating efficiency is low. And the compressor needs to continuously work under the condition of a large pressure ratio, so that the load is large, and the service life is short. The refrigerating system comprises a refrigerant refrigerating system and a cold carrying system, the cold carrying system comprises a subcooler and an air cooler, the subcooler is connected with the refrigerant refrigerating system, and the air cooler is connected with the air cooler. By adjusting a control valve of the refrigerator refrigerating system, a refrigerant discharge