A Identification Method of Inertia Distribution Based on Disturbance Propagation Characteristics

Inertia is an inherent property of power systems that enables them to withstand external disturbances and maintain stability. With the integration of large-scale renewable energy sources into the grid through power electronic devices, the effective inertia of the system decreases, leading to an increased risk of frequency stability incidents. Therefore, assessing the adequacy of inertia and its distribution in the grid has become necessary. In this study, a mathematical model is established based on the propagation characteristics of electromechanical disturbances, and a mapping relationship between disturbance propagation velocity and system inertia is derived. Furthermore, a method is proposed to calculate the propagation velocity of disturbances in different regions based on the location of disturbance occurrence and the time difference of disturbance propagation. On this basis, a non-intrusive method for identifying the inertia distribution in large-scale power system is proposed. The effectiveness of the proposed method is validated using an actual large-scale power grid model in western China.