The Application Of A Generator Coherency Identification Method Based On Linearization In Complex Power System

The paper introduces a practical generator coherency identification method based on the linearization of non-equilibrium points. The oscillation modes between generators can be obtained using the eigenvalues of coefficient matrix of linearized models. In both cases all the eigenvalues are non-positive or not, the dominant oscillation mode affecting rotor angle trajectories are determined. Then a concept of coherency index is defined according to the eigenvector corresponding to the dominant oscillation mode and the detailed procedure of generator grouping is presented based on the coherency index. Using this approach, we can identify generator coherent groups continuously along the trajectory. Finally, simulations on IEEE 39-bus and IEEE 118-bus test systems verify the practicability and validity of the proposed method.