Identification of Dominant Mode of Grid-forming Inverter System Based on Prony Algorithm

The power system has gradually developed into a new power system with a high proportion of new energy and a high proportion of power electronic equipment. A large number of new energy sources are connected to the grid through power electronic shunt converters, which makes the system prone to broadband oscillation. Grid-forming converters can suppress broadband oscillation and become a key development direction. This paper studies the identification of oscillation modal parameters in the grid-connected scenario of grid-forming converters. First, the basic principle of grid-connected converters is introduced, and the corresponding model is built based on the Matlab/Simulink simulation platform; then the extended prony algorithm is used to extract oscillation characteristics, and the setting method of algorithm parameters is discussed; finally, the accuracy of the method in this paper is verified by comparing the results of the eigenvalue analysis method.