A sensitivity analysis of eigenstructures [in power system dynamic stability]

The concepts of condition number, taken from numerical linear algebra combined with logarithmic sensitivity are applied to analyze the robustness for model uncertainty of power systems eigensets. Sensitivity matrices to facilitate the estimations of the eigenvalue sensitivities in relation to elements of the state matrix are proposed. Eigenvector derivatives are analyzed and it is evidenced the trend of power system eigenvectors to present large sensitivities. A case study of a realistic single machine with excitation system connected to an infinite bus example is presented. Lack of stability robustness and also of eigenvector robustness are demonstrated.