Abstract: With the development of social economy,the power demand increases greatly,and the complexity of power system increases,which makes the transient stability analysis more difficult.Numerical simulation is usually used to analyze the stability of power system.In order to improve the reliability of numerical simulation,it is urgent to model the demand side and new energy components of large power grid.A refined modeling method for new energy access to large power grid was proposed based on the power system analysis software package（PSASP）,which is different from the traditional equivalent modeling. The traditional equivalent model and topology model were used to model a receiving power grid,and the voltage stability under different models was compared and analyzed.The proposed modeling method provides a reference basis for analyzing the dynamic characteristics of power grid considering high penetration of new energy resources.