Blue sky bifurcations caused by unstable limit cycle leading to voltage collapse in an electric power system.
This paper deals with the study of bifurcations which lead to voltage collapse in an electric power system. The electric power system considered in this paper, is the single-machine infinite-bus system including the load connected to the intermediate point of the transmission line. The load is composed of the induction motor, the constant reactive power load, and the capacitor in parallel with the load. For smaller values of the capacitor, voltage collapse has been identified as a chaotic blue sky bifurcation, which is caused by the unstable limit cycle. The limit cycle generated by a supercritical Hopf bifurcation of a stable equilibrium vanishes with the unstable limit cycle by a cyclic fold bifurcation. For medium values of the capacitor, voltage collapse is caused by this cyclic fold bifurcation. Moreover, a variety of nonlinear phenomena, including chaotic attractors and coexisting limit cycles, is observed.
scientific article; zbMATH DE number 2026961