Coordinated Distributed Service Restoration Strategy for Interconnected Distribution Networks under Main Transformer Fault

The main transformer fault will cause a complete blackout of the distribution network (DN) it supplies, with a wide range of power outages and significant losses. In this context, this paper proposes a coordinated distributed service restoration strategy for multiple interconnected DNs to respond to the main transformer fault. Through utilizing the tie-lines between the power outage and normal DNs, as well as the coordinated regulation of controllable resources in DNs, the proposed restoration strategy strives to reduce the scope of power outage of DNs. The normal DNs optimize the transmission capacity margin of the interconnected tie-lines between DNs and exchange the boundary variables with power outage DN. And then the power outage DN determines the internal load transfer scheme based on the boundary information to achieve the maximum load power restoration. Four IEEE 33-node systems connected by tie-lines are taken as an example in this paper to verify the effectiveness and feasibility of the proposed distributed service restoration strategy for interconnected DNs.