Gas storage system and gas taking method

The invention relates to a gas storage system and a gas taking method. The system comprises a storage tank group, a compressor unit with a preset order of magnitude and a control device connected with the compressor unit. Each storage tank in the storage tank group is independently connected with an inlet main pipeline of each stage of compressor unit; the control device is used for controlling the compressor unit to take gas from the storage tank set in a stepped gas taking mode. And each storage tank can be independently connected with the compressor unit of each grade, so that the device is suitable for a traditional gas taking mode and is also suitable for a stepped gas taking mode, and the gas taking mode is more flexible. In addition, the pressure of each storage tank can be changed independently and is not affected by other storage tanks, it can be guaranteed that gas with multiple levels of pressure exists in the system, and the adjusting capacity of the system is improved. According to the system, th