A generalized method of power oscillation characteristic analysis for multi‐VSC grid‐connected system

Abstract The grid‐connection of high‐permeability new energy through voltage‐source converters (VSCs) brings new oscillation risks to the power system, which seriously threatens the stable operation of the system. Therefore, an evaluating method based on modal analysis is proposed to investigate the power oscillation characteristics in a multi‐VSC grid‐connected system. Initially, based on the analogy method, the output admittance model of voltage‐source controlled VSCs (VC‐VSCs) and current‐source controlled VSCs (CC‐VSCs) is established. Subsequently, the output admittance model of a multi‐VSC grid‐connected system is constructed. Then, the modal analysis method is introduced to investigate the power oscillation characteristics of VC‐VSCs and CC‐VSCs, and the influence factors of power oscillation and its variation law are analysed. Next, a sensitivity analysis is also employed, which helps to identify the origin of each oscillation mode and determine the contribution of each component to the power oscillation. Finally, simulation and experiment are carried out to verify the effectiveness of the above analysis method.