Analysis of low frequency oscillation in multi-area power system based on incomplete elliptic integral

The stability of power system is an important index for safe operation of the system. With the expansion of interconnection scale of power system and the increasing transmission line power, the low frequency oscillation has gradually become a significant cause of the system instability. In this paper, based on incomplete elliptic integral, a new nonlinear method for low frequency oscillation frequency computation and analysis is presented, which can be useful for prediction and evaluation of the anti-disturbance ability in multi-area power system. By the equivalent simplification and construction of Hamilton energy function, an exact expression of the low frequency oscillation frequency is obtained. Simulation studies of the proposed method are conducted in the New England 10-generator 39-bus system and the influence of different disturbances is discussed to verify the correctness and effectiveness of the method. Comparative analysis with traditional linearization method demonstrates that the performance of the new approach is inspiring, and it is of higher processing efficiency as well as reliability.