Improvement of order reduction approach for special modes in power system small signal stability analysis

Abstract

Precise results of eigenvalues can be obtained in order reduction approach for special modes. To improve calculation efficiency, the order reduction approach is analyzed in this paper. In the process of order reduction, every set made up of retained state variables is shared by different modes, which reduces calculation amount. Based on real number expression of complex matrix, the expression of outer iteration is reformed. Factor table formed by the sequence elimination can be used to solve inverse matrix quickly. The function of parallel computation in Open Multi-Processing is introduced to accelerate calculation on multi-core computers. The improved effect of retained sets, sparse technique and parallel computation is tested and analyzed by a 105-machine system.