Spare power automatic switching control method of double-loop network type power distribution network

The invention relates to a spare power automatic switching control method of a double-loop network type power distribution network, belongs to the technical field of power distribution network relay protection, and solves the problem that the existing switching station spare power automatic switching step-by-step matching mode is not suitable for double-loop network wiring. In the invention, when a line on a main line and/or a switch station bus has a fault, the method comprises the following steps: performing fault isolation; respectively judging whether each power-losing switching station bus of a non-fault section meets an island operation condition or not, if so, controlling to operate in an island mode, and locking a segmented spare power automatic switching device; if not, controlling to execute a self-healing action, and locking the segmented spare power automatic switching device; when the self-healing fails, the segmented spare power automatic switching device of the switching station is controlled t