Power Grid Development Planning Based on Small World Model

There are two main directions of the further development of power grid. One is the construction of higher voltage power grid. The other is strengthen power grid by keeping the original voltage grade. The current research of the two power grid directions focuses on comparing of specific project. The essence laws of power grid and its boundary conditions are less researched. In view of the above problems, this paper proposes a development simulation method of power grid based on small world evolution model. The method is based on the small world characteristics of power grid. And adaptability index for power grid are built. They can reflect adaptability of power grid to boundary conditions of essence laws. The grid development direction is established based on the adaptability index. It is fit to power grid situation and external environment. The simulation results of power system development show that proposed method is effective. Introduction At present, most of China's power grid has formed a 500 kV backbone grid. In developed areas such as East China and South China, 500 kV power grid has developed rapidly. Some local saturation phenomena such as short-circuit current exceeding the standard have appeared. How to determine the next stage of development direction of 500 kV power grid is one of the hot issues of current research [1-3]. Reference [4] puts forward a scheme to solve the saturation problem of 500 kV power grid by constructing UHV AC power grid, and demonstrates the rationality and security of the scheme. Reference [5] further discusses some controversial issues in the field of UHV transmission in China, and draws a conclusion that the development and application of UHV transmission and transformation technology in China must be strengthened. However, literature [6] thinks that 500 kV power grid can solve the saturation problem of 500 kV power grid technically by improving the regional backbone grid and other measures on the basis of the existing grid structure. And this case has more economic advantages. Above all, there are two main development directions in the next stage of 500kV power grid. One is to upgrade to high voltage level. The other is to maintain the original voltage level to optimize and strengthen. At present, the two directions of development are often discussed from their respective perspectives. The research content is mostly focused on the analysis of specific technical aspects. While the research on the essential law of power grid development is less. For different areas of the grid, the grid structures are different. These grid all are large-scale artificial network which belongs to the category of complex networks. They are in line with the general law of complex networks [7]. With the expansion of the grid scale, it will generally evolve into a small world network. Documents [8-10] confirm this trend and point out that some power grids in China, the western United States, Italy and Brazil have developed into small-world networks. References [11] and [12] considered the characteristics of the small-world network of the power grid based on the small-world model. The above studies confirm the small-world nature of the grid. But the above studies are mostly limited to the performance analysis of the specific state of the grid. While, the small-world dynamic evolution of the grid is seldom studied. In view of the above problems, this paper first establishes the evolution model of small-world network. Then, the two main directions of the evolution of small-world network are compared and