Research on Identification Approach of Coherent Groups of Generators Based on Elbow Judgment

In the large-scale power system transient stability analysis, dynamic equivalence approaches can be adopted to simplify the system in order to reduce the amount of numerical simulation calculation. However, the traditional dynamic equivalence methods mostly judge the number of clusters of coherent generators based on experience. For this reason, according to the gap static algorithm (GSA), an approach of coherent groups of generators based on elbow judgment was proposed in this paper. This approach can effectively identify the optimal number of clusters of coherent generators, thereby providing the basis for dynamic equivalence. The results from PSD-BPA based simulation of IEEE 39 bus test system showed that the clustering results were reasonable. The equivalent system was able to fully reflect the dynamic characteristics of the original system, and the effect of dynamic equivalence was ideal, which verified the effectiveness of this approach.