1996 Volume 116 Issue 11 Pages 1361-1367
This paper proposes an efficient algorithm for small signal stability analysis by means of the Arnoldi method with the S-matrix transformation. In the proposed algorithm, the Arnoldi method evaluates several eigenpairs of large scale matrix with less execution time, while the S-matrix transformation makes dominant eigenvalues corresponding to low damped oscillation modes. The combined use of these techniques enables to calculate only critical eigenvalues of large scale power systems efficiently. The Amoldi method has a specific feature that it can obtain eigenvalues successively from the outer part of their distribution. By making use of this characteristic, the spectral transformation can be simplified, thus improving calculation efficiency. The, proposed method is also useful to understand the shape of the spectrum by investigating all of the obtained eigenvalues including non-converged ones. The algorithm has been successfully applied to a large scale power system which has 220 generating units and 3000 state variables.