Chaotic phenomena and small signal stability region of electrical power systems

In this paper, chaos phenomena and its influence on the power system small signal stability region (SSSR) are studied. We first review the studies on the SSSR, and point out that it is very important to make clear whether the re exist some chaotic components on the boundary of the SSSR. Next, with so me analytic skills of nonlinear dynamic system, we give a complete bifurcat ion diagram of a chaos existing in a sample power system, from a limit cycl e (period-1) to chaotic state through cascading period-doubling bifurcation . The characteristics of the system energy varying in the continuous bifurc ation are also shown. Thus a conclusion that chaos is always out of the Hop f bifurcation components (HB) on the SSSR's boundary. Based on this conclus ion and some further studies, we confirm that, from the viewpoint of power system engineering, we do not need to consider the existence of chaos in th e SSSR and its boundary. Therefore greatly simplifying the study of SSSR. M oreover, some aspects of the attractive regions of chaos and limit cycle ar e also studied, which is helpful to understanding some mistakes in some pre vious articles.