A study on the multiswing instability region using Hopf bifurcation theory considering energy threshold

Transient stability is treated as one of the important constraints for calculating available transfer capability (ATC), especially in Japan. Therefore, to improve the time required for ATC calculation, development of high‐speed transient stability analysis is required. For this analysis, a screening method that can recognize the serious case of fault will be greatly effective to solve the problem. Many screening methods on the first swing instability are proposed these days. However, a method based on multiswing instability has not been developed and its characteristic is not understood clearly. In this paper, the relationship between the nonlinear limit cycle and the energy function of a power system is examined using the Hopf bifurcation theory. A calculation method, which gives the critical transfer capability considering multiswing instability, is proposed. © 2006 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.