Abstract: Distributed power stations are interconnected to form a distributed power station network. In a distributed power station network, there are also different compositional structures. These structures are small subnets, which is called distributed power station subnets. Firstly, the three basic structures including linear structure, circular structure and star structure are studied in distributed power grid network. Next each subnet of the three different structures is respectively connected to IEEE30 and IEEE57 system. It is found that in the three distributed power station subnets, when the central node of the star distributed power station subnet is connected to the power grid, the network average distance is the smallest and the network synchronizability is the best, which shows that the star structure is best suited as a substation structure of a distributed power station subnet. Subsequently, the distributed power stations are connected as a star-like BA distributed power station subnet and are connected to the grid. It is found that with the expansion of the subnet scale of the distributed power stations, the average distance of the network will increase and the synchronizability of the power grid will be weakened. Meanwhile with the increasing of edges between the distributed power station subnet and the power grid, the network average distance decreases and the network synchronizability gets better and finally tends to a stable value.

Key words: distributed power station, distributed power station network, network average distance, synchronizability, critical coupling strength