DYNAMICAL ANALYSIS OF VOLTAGE COLLAPSE IN LONGITUDINAL SYSTEMS

In this paper an analysis of the voltage collapse phenomenon in longit udinal systems is presented. The analysis is performed through a small signal perturbation approach where the nonlinear multimachine dynamic model is linearized around a steady-state operating point, and the st ability of the system is evaluated through the eigenvalues of the Jaco bian matrix of the dynamic state equations. The analysis clarifies the difference between the maximum loadability point and the voltage stab ility limit. In addition, a voltage collapse proximity indicator, taki ng into account the dynamic of the system, is proposed and tested in t hree different networks.