Identification of Weak Nodes Based on the Norm of Inertia Distribution of Power Grid Nodes

Due to the uneven distribution of generators in the actual geographical location of the power grid, and the high proportion of new energy infiltration in the New power system, not only does it reduce the system inertia but also leads to a more uneven distribution of the system inertia. After the disturbance occurs, the frequency of the power grid also shows a significant spatiotemporal distribution characteristic. Therefore, This paper proposes an inertia evaluation method for power grid nodes based on the inertia distribution norm and applies it to identify weak nodes in the power system. Firstly, considering the frequency distribution characteristics and inertia distribution characteristics, and combining them with the L2 norm, recognize the key node in the power system. Then, collect and compare the frequencies of each node and key node from the disturbance to the addition of primary frequency modulation, and normalize them to form the node inertia evaluation index. Finally, an improved IEEE14 node system simulation model was built using MATLAB/Simulink, and the inertia levels of each node were evaluated using the proposed method. The weak nodes of the system were identified, validating the feasibility of the proposed method. This also provides reference for the subsequent development of control strategies for inertia support and frequency regulation capabilities of power system.