Calculation of Node Critical Inertia Compensation of Multi-machine System Based on Inertia Spatio-Temporal Distribution Characteristics

Aiming at the frequency distribution of different nodes of the new energy power system when perturbation occurs, the node computational inertia index is defined to characterize the ability of a single node in the grid to resist the system frequency change after perturbation, and to quantify the inertia distribution characteristics of the system. Considering the physical structure and parameters of the power grid, the expression of the node calculation inertia of the multi-machine system is deduced, and an example simulation is carried out through the IEEE39 node system, which verifies the correctness of the node calculation inertia, with an average error of 8.7%, and the lowest can reach 0.1%, and the simulation results show that the proposed node calculation inertia can accurately characterize the inertia distribution of the new energy power system, and the final calculation result proposes a new node inertia index for the multi-machine system based on the node inertia. Finally, a critical inertia compensation calculation method for multi-machine system is proposed based on the nodal inertia calculation results, and the results show that the proposed method can improve the level of nodal inertia very well.