Centrifugal compressor rotor structure

The utility model belongs to the technical field of centrifugal compressors, and particularly relates to a centrifugal compressor rotor structure. A centrifugal compressor rotor main shaft is sleeved with a plurality of impellers, spacer bushes installed on the rotor main shaft in a sleeved mode are arranged between the impellers, shaft sections, corresponding to the spacer bushes, of the rotor main shaft are provided with annular grooves respectively in the circumferential direction, and the widths of the annular grooves in the axial direction are smaller than the lengths of the corresponding spacer bushes. By means of the centrifugal compressor rotor structure, the centrifugal compressor rotor mechanical property is optimized, the rotor weight is lightened, a bearing and shaft-end seal are selected in a downshift mode, and meanwhile the whole machine can be compact in structure.