A New Coherency-based Dynamic Equivalence Algorithm with Complex Network Theory

A new coherency-based dynamic equivalence algorithm is proposed in this paper based on the complex network theory. Firstly, the Laplace matrix is constructed for dynamic power grid, which is symmetrical and similar with the state matrix. Based on the Laplace matrix, the power grid is divided into two districts with the help of the spectral bisection method. The district, which contains the generator with least synchronizing weaken index, is chosen as the study district, while the other one is taken as the external district. Furthermore, the external district is separated into several equivalent areas taking advantage of aggregation method and modularity index. The simulation results on IEEE-39 bus system show that, the study district is distinguished automatically from the system, and the optimal division scheme is determined for external district with little computation.