由于用电负荷日益增长,佛山地区电网的部分110kV变电站要在已有两台主变的基础上扩建第三台主变,为了提高供电的可靠性和连续性,在扩建的10kV母线和相邻的10kV母线之间需增加一套10kV分段备自投。这对3台主变变低侧的两套10kV分段备自投功能的配合提出了避免动作范围叠加的要求。本文叙述了使用两套典型的备自投装置实现三主变接线的10kV分段备自投功能的设计,提出解决两套10kV分段备自投之间的相互配合方案。 Due to increasing power load, part of the 110kV substation in Foshan power grid should expand the third main transformer on the basis of two main transformers. In order to improve the reliability and continuity of power supply, Of 10kV busbars need to add a set of 10kV sub-automatic switch. This 3 sets of low-side of the main transformer two sets of 10kV sub-automatic switch function with the proposed action to avoid overlapping range of requirements. This paper describes the design of two 10kV subassembly devices using two sets of typical self-throwing devices, and proposes a solution to the mutual cooperation between two sets of 10kV subarea devices.