Abstract:With the gradual increase of the penetration rate of new energy mainly dominated by scenery, the impact of the uncertainty of its output on the power grid is also gradually increasing. To solve this problem, this paper proposes a method to divide the penetration rate of new energy in regional power grid by stages. First of all, this paper expounds the principle of dividing the development stage of regional power grid including new energy in time, and divides it according to the flexible supply and demand relationship. Then, a quantitative evaluation of power grid flexibility resources is carried out to comprehensively consider the flexibility supply and demand of different forms. The ability of regional power grid to absorb new energy access is obtained by analyzing the example of 10-machine system. When the penetration rate of new energy reaches a certain threshold, the development of power grid has entered the stage of high permeability of new energy, and regional saturation may occur. The study found that the threshold was also different in different grids. The method proposed in this paper can provide reference for power system planning and operation, so as to improve the stability and reliability of power grid.