A new eigen-analysis method of steady-state stability studies for large power systems: S matrix method

The authors discuss an advanced version of the S matrix method, an eigenvalue technique for the analysis of the steady-state stability (or the stability against small signals) of large power systems. The dynamic characteristics of power systems can be linearly approximated with a set of differential equations. The technique transforms the matrix A into the matrix S and then determines several eigenvalues with the largest absolute values from matrix S that correspond to the dominant eigenvalues of matrix A. In the process of identifying the appropriate eigenvalues, the method uses the refined Lanczos process, which makes high-speed calculation possible through the use of the sparsity and the structural uniformity of matrices