Chaotic and subharmonic oscillations of a nonlinear power system

In order to analyze complex oscillations with a large deviation for a nonlinear nonautonomous power-transmission system, heteroclinic and subharmonic bifurcations are discussed by technically computing Melnikov functions with the residue of a complex function and elliptic integrals, which gives a condition of parameters for chaotic oscillation and one for periodic oscillation. We describe the three-dimensional geometric structures of these parameter regions and the geometric relations among them. According to these regions, numerical simulations are implemented to demonstrate chaotic phenomena and subharmonic oscillations.