Expansion Planning of the Target Connection Mode in Medium Voltage Distribution Network with Complex Connection

The previous studies have not identified an effective solution to the complex connection of the distribution network and how to transition the distribution network to the target connection mode in the case of complex contact. In order to solve the above problem, this paper presents a multi-period distribution network expansion planning (MDNEP) with complex connection. Firstly, distribution network connections are divided into five categories based on its characteristics: invalid, bottleneck, critical, multiple, and standard connection, and proposes corresponding planning strategies for elimination, transformation, construction, simplification and solidification. Secondly, the target connection constraint of the proposed MDNEP is represented by the number of interconnected line groups, and the benefits of grid refinement are integrated in the objective. Then, the dynamic programming algorithm based on parallel state reduction is proposed to solve the model, which improves the solving efficiency. Finally, the effectiveness and feasibility of the proposed method are verified by the improved Portugal54 bus system.