عنوان مقاله [English]
Nowadays, Voltage stability is an important types of power system stabilities. To analysis of voltage stability, different static and dynamic boundaries such as maximum Loadability point (MLP) and bifurcation points such as saddle node bifurcation (SNB), hopf bifurcation (HB) and limit induced bifurcation (LIB) are introduced. Bifurcation theory that is based on the eigenvalue analysis is an effective method to evaluation of voltage stability and its boundaries. Moreover, load models, over-excitation limits of generators and auto-regulator of transformers will affect voltage stability. Therefore, in this paper, the Hopf bifurcation boundary of voltage stability feasible region is analyzed by combination of time domain simulation (TDS), bifurcation theory and modal analysis of dynamic Jacobian matrix of power system. Effect of different load models, reactive power generation limits of generators and excitation system parameters on voltage stability dynamic loading margin (especially HB) is evaluated.