Coordinated Planning Method of Distribution Transformer and Distribution Line for Seasonal Load

Taking into account power supply reliability, this paper proposed an optimal planning method adapting to seasonal load for distribution transformer network in order to improve equipment utilization efficiency in rural coal-to-electricity conversion areas. The main idea was firstly to establish low-voltage tie-line between distribution transformers, and according to seasonal load characteristics, some distribution transformers could withdraw from operation in low-load season by switching the tie-line operation state and mode. In this method, a bi-level programming model of distribution transformer network was constructed to minimize the overall cost. Voronoi method was used to plan the distribution transformer at the upper level; Prim algorithm was used to plan the low-voltage power supply line at the lower level, and genetic algorithm was used to seek the optimal solution. Finally, the feasibility of the method was verified by the distribution planning of typical power supply areas, and it can reduce the distribution transformer loss and improve the reliability and economy of power supply.