Abstract: Flexible multi-state switch is a new kind of intelligent distribution device. Considering the functional characteristics， the requirement of partitioning distribution network with flexible multi-state switches is proposed. According to the theoretical framework of the multi-level graph partitioning， a partitioning method which contains of three stages of coarsening， partitioning and refinement is proposed. In the coarsening stage， a method aiming at minimum electrical distance is given. After the initial partitioning is completed by the greedy growing graph partitioning algorithm， the preliminary splitting boundary will be refined by the path searching algorithm. The proposed method can not only optimize the operation indices of the distribution network， but also increase the flexibility and controllability of the distribution network. IEEE 118-node test system is used to demonstrate and validate the effectiveness of the splitting strategy. As for the partitioning result， further analysis is made while considering the regulation of flexible multi-state switch. The result shows the partitioning method can not only improve the average feeder load balance index， but also improve the feeder load balance and voltage distribution cooperated with the regulation of flexible multi-state switch.

Key words: flexible multi-state switch, partitioning method, multi-level graph partitioning, feeder load balance index, distribution network