Authors

Abstract

In the steady-state contingency analysis, the traditional Newton-Raphson method suffers from non-convergenceissues when solving post-outage power flow problems, whichhinders the integrity and accuracy of security assessment. In thispaper, we propose a novel robust contingency analysis approachbased on holomorphic embedding (HE). The HE-based simulatorprovides theoretical convergence guarantee, which is desirablebecause it avoids the influence of numerical issues and providesa credible security assessment conclusion. In addition, basedon the multi-area characteristics of real-world power systems,a partitioned HE (PHE) method is proposed with an interfacebased partitioning of HE formulation. The PHE method does notundermine the numerical robustness of HE and significantly reduces the computation burden in large-scale contingency analysis.The PHE method is further enhanced by parallel or distributedcomputation to become parallel PHE (P2HE). Tests on a 458-bussystem, a synthetic 419-bus system and a large-scale 21447-bussystem demonstrate the advantages of the proposed methods inrobustness and efficiency.