A Method for Dynamic Security Assessment of Power Systems with Simultaneous Consideration of Hopf and Saddle-Node Bifurcations

This paper presents a methodology to identify the stability margin in the safety region due to Hopf (HB) and Saddle-Node (SNB) Bifurcations. The safety region due to the HB corresponds to the limit of damping of 5% for all eigenvalues of the linear model of the power system, and the safety margin due to the SNB corresponds to 96% of the load of the SNB point. The proposed methodology is based on linear models. In order to improve the convergence of the algorithm, parallel computation, pre-conditioning of the initial conditions of the variables and a method to handle the sparsity of the linear model was used. The proposed methodology was applied in the IEEE 39 bus benchmark power system considering the load base case and the N-1 contingency criterion of transmission line disconnection.