Analyzing dynamic performance of power systems over parameter space using normal forms of vector fields. II. Comparison of the system structure

Summary form only given. For pt. I see ibid., p. 1301 (2001). Part I proposed an approach to identify unfavorable operating regions by searching for resonance and near-resonance. The results show that near-resonance among critical inertial modes and control modes may contribute to the unsatisfactory behavior of the system. In this paper, the effect of strong nonlinear modal interactions on machine states is quantified. A new index is derived to measure the relative severity of the near-resonance. The linear and nonlinear characteristics of the system are separated and correlated to the transient stability of the system.