Aiming at the key factors affecting the dominant behavior characteristics and synchronization stability of new energy power supply synchronization stability, this paper takes new energy power supply as the research object, aiming to extract the main characteristics of new energy power supply synchronization stability from a large number of simulation data, and clarify the relevant influencing factors of synchronization stability. Firstly, the synchronization control strategy of the existing new energy power supply is divided into the synchronous control of the grid-connected type and the grid-connected type, and the principle of single-machine grid-connected synchronization stability of these two types of new energy power supply is summarized. Secondly, a k-nearest neighbors (KNN) algorithm is proposed to realize the classification of simulation data under different grid strength or new energy penetration. Finally, the power supply simulation system of grid-connected and grid-connected new energy is built on the Matlab/Simulink simulation platform, and the influence of grid strength and new energy permeability on the synchronous stability of new energy power supply is analyzed.