Post-contingency equilibrium analysis of power systems

This paper presents alternative methods to compute the equilibrium condition immediately following a disturbance to an electric power system. The first uses the brute force method of simply integrating the dynamic model until it reaches steady state. The second uses the straightforward analytical choice of setting all time derivatives of the dynamic model to zero and solving the remaining algebraic equations for the equilibrium values of the dynamic states. This method requires the creation of new commercial software to solve the large-scale network algebraic equations simultaneously with the dynamic equilibrium equations. The third uses a method that takes advantage of existing commercial load flow software to perform the major portion of the solution process. These load flow solutions then iterate with the de-coupled algebraic equations for each generator.