Abstract: The grid connection of different types of generators helps to improve the utilization rate of equipment and relieve the power consumption difficulties of small power grid capacity and difficult start-up of high-power equipment during the construction period of mine project infrastructure. By fully considering the technical and economic feasibility，combined with engineering examples，the technical path of grid connection of diesel generators with different voltage levels，grounding forms and capacities is explored. By adding step-up transformers and installing special grounding transformers，the voltage and grounding mode of low-voltage and high-voltage generators are consistent，so as to meet the prerequisites for grid connection.

Key words: parallel diesel generator, neutral point solid grounding, high resistance grounding, grounding capacitive