Spare power automatic switching device and system

The invention discloses a spare power automatic switching device and system, and belongs to the field of transformer substation multi-terminal communication. The spare power automatic switching device is provided with more than one communication interface, and the communication interface obtains operation data of a corresponding transformer substation; the processing unit comprehensively judges the operation conditions of the connected transformer substation and the transformer substation according to the operation data of the connected transformer substation and the operation data of the processing unit, and analyzes the position of a power grid fault point according to the operation conditions; according to the scheme, the problem that an existing single-end spare power automatic switching device cannot achieve the spare power automatic switching function of interconnection of a plurality of power supply stations is solved. 本发明公开了一种备自投装置和系统，属于变电站多端通讯领域，该备自投装置通过设置一个以上的通讯接口，通讯接口获取对应变电站的运行数据，处理单元根据所连接的变电站的运行数据