Ice cold accumulation set, air conditioning system using same and controlling method thereof

In the invention, a supercooled ice cold-storage unit comprises an ice-storage device, a closed circulating pipeline and three external connection points. On the closed circulating pipeline passing through the ice-storage device there is a electronic expansion valve and three magnetic valves, and one magnetic valve is in parallel connection with the electronic expansion valve and the other magnetic valves are in parallel. The first external connection point is located on one side of the electronic expansion valve, the second one is located between the magnetic valve and the ice-storage device and the third one is located at once end of the magnetic valve.