Identification of coherent generators using frequency response

The paper presents a new method for identifying coherent generators under various power-system disturbances. A coherency index, which is introduced by using frequency response of the simplified and linearised power-system model, is proposed for evaluating coherent generators. The method is applied to a power system constructed with ten machines and 39 busbars, and the efficiency of the method is investigated under various system disturbances. The results prove that the proposed method is highly effective in the identification of coherent generators under various system disturbances. Moreover, it is also recognised the case in which various regulator actions and flux that the proposed method may be easily applied to decays may be taken into account