A refrigerant circulation system comprises a control system and an electronic expansion valve. The control system comprises a central processing module (26), a step drive control module (27), and a drive module (28). The running of the electronic expansion valve in the refrigerant circulation system comprises an initialization running stage and a flow adjustment running stage, motion speeds in the stages are adjustable, in the flow adjustment running stage, the maximum motion speed is less than or equal to the maximum motion speed in the initialization running stage, and in the flow adjustment running stage, the minimum motion speed is less than or equal to the minimum motion speed in the initialization running stage, so that stable and fast adjustment of the system can be implemented, and the system keeps stable running.
