Frequency stability in modern power network from complex network viewpoint

Abstract

Grid-connected operation of Renewable Energy and Storage (RES) nodes make the dynamics of modern power grid to be more complex. A model of power grid, considering RES nodes, is being proposed to address frequency synchronization and stability analysis. First, a unified dynamical model of four different types of nodes are established according to the swing equation, including the RES nodes with power-frequency droop inverter controllers, and the storage nodes with charging and discharging states. Second, based on the multi-agent linear time-varying protocol, the stability of the frequency synchronization solution of power system is given by a theorem, which is significant for theoretical progress and practical engineering applications. Third, verification and validation are carried out by simulation experiments and case study in local grid such as Western System Coordinating Council and the Shaanxi North Power Grid model.