Refactored bi-iteration: a high performance eigensolution method for large power system matrices

Small-signal stability analysis of interconnected power systems involves the computation of many eigenvalues/eigenvectors of very large unsymmetric matrices. A new numerical linear algebra method for the partial eigensolution of large sparse matrices is described in this paper. The method converges to as many eigenvalues as the number of trial vectors utilized, in a reduced number of iterations. The results presented are limited to the study of low frequency oscillations in electrical power systems, but the proposed method is completely general.