Research on the Impact of Grid-Forming Energy Storage on Inertia Distribution Characteristics of Power System Based on Frequency Trajectory

The proportion of new energy in the new power system is continuously increasing, which has changed the inertia distribution characteristics of the power system. Grid-forming (GFM) energy storage has the characteristics of active inertia, which can realize grid support and maintain power system stability. In order to quantitatively evaluate the inertia support capability of grid-forming energy storage and other asynchronous electromechanical sources, this paper first constructs an inertia response model for grid-forming energy storage on the basis of the grid-forming technology. Then, based on the principle of inertial dynamics equivalence, the concept of power system inertia is expanded, and an evaluation method based on frequency information is proposed to assess the inertia distribution characteristics of the power system. According to the evaluation method and inertia response model, the improvement effect of grid-forming energy storage on the inertia distribution characteristics of the power system is evaluated. Simulation results have verified the effectiveness and scalability of the proposed method, confirming the improvement effect of grid-forming energy storage on the inertia distribution characteristics of the power system.