A new approach for calculating the average frequency of power system based on the identification of regional inertia center nodes

The grid structure of the modern power system is complex and the space span is large. When the power system is disturbed to generate unbalanced power, the transient distribution process among the various synchronous units leads to the spatiotemporal distribution characteristics of the frequency response of the system. By measuring the generator Frequency and Inertia, the inertia center frequency can be calculated. Based on the two-generator system, the relationship between generator frequency and bus frequency is analyzed. A method for selecting the frequency inertia center node of the local power grid in the power system is proposed, and the inertia center frequency of the system is estimated based on the measured frequency at this point. Taking 10 machines and 39 nodes as an example, the simulation calculation is carried out to verify the effectiveness of the proposed method.