Towards Faster Givens Rotations Based Power System State Estimator

Nunierically stable and computationally efficient Power System Statc Estimation (PSSE) algorithms are designed using Orthogonalization (QR decomposition) approach. They u3e Givens rotations for orthogonalization which enables sparsity exploitation during factorization of large sparse auginentecl Ja,cobian. Apriori row and column ordering is usiially performed to reduce intermediate a.nd and overall fills. Column ordering methods, usually based on Minimum Degree .4lgorithm (T\ID.4), have matured. However, t,heir exists a significa.rit scopc for improving the quali t,y of row ordering. This paper introduces a new row ordering technique for Givens rotat*ions based power system staw est,imators. The proposed row processing method (IT-4IR) requires a shift, from conventionally used row orieiited QR decomposition impl6mentation to a column orierl:.ed QR decomposit,ion implement,ation. It is deII-lonstrht.rd that, the proposed colur in oriented Q R decompositio,i algorithm which uses iZ/ID:i for column ordering and VP.1 IR for row ordering can lead t,o a. milch faster PSSE. These aspects are justified by simulations on large power systems.