Dynamic bifurcations in a power system model exhibiting voltage collapse

Bifurcations are studied for a power system dynamic model which has previously been used to illustrate voltage collapse. It is found that for this model, the nominal operating point undergoes dynamic bifurcations prior to the static bifurcation to which voltage collapse has been attributed. These dynamic bifurcations result in a reduced stability margin in parameter space. Moreover, a short oscillatory voltage transient typically occurs prior to voltage collapse for this model. In addition, it is found that the model admits large-amplitude bifurcations, including cyclic fold and period-doubling bifurcations; the latter leading to period-doubling cascades and the resulting chaotic behavior