The continuous expansion of the power supply grid scale and the high proportion of renewable energy access make the dynamic change characteristics of the grid load more and more significant, and the traditional power supply grid division method has been difficult to adapt to the complexity and variability of the power supply operation requirements. In this paper, the research of scientific planning method of power supply grid is carried out. By clarifying the definition of power supply unit, and based on the load transfer mode of the regional scope. Corresponding the planning area to different power supply grids, combined with the load characteristics, the grid planning process of power supply grids is designed. The trend extrapolation method is selected as the load forecasting method within the built-up area with high regional development level. Meanwhile, a gray Verhuslat model is established to correct the prediction data and improve the prediction accuracy. After obtaining the load characteristics of the grid, the division of power supply is carried out on the basis of power supply grid division, and the power supply unit division model is constructed. Considering the technical differences between inter-station and intra-station power supply unit division, a technical framework of power supply unit division order and iterative division is proposed. By optimizing the power supply units under dynamic load, the grid division within the power supply area is completed. By using this model to optimize the grid division of power supply in the W area, it is expected that the line insulation rate, the line power supply radius compliance rate and the power supply automation coverage rate will be increased to 100%, which can satisfy the load development demand and power supply reliability in the area.
