WLS State Estimation Method of Distribution Network Topology Partition Based on Phase Measurement Unit

In view of the problem that the complex structure of distribution network and the low measurement data cause the low accuracy of distribution network state estimation, a distribution network weighted least square state estimation method based on phase measurement unit and network topology partitions is proposed.Firstly, based on the analysis of the network connectivity and the equilibrium degree of each partition, the topology partition model of the distribution network is established, and the distribution network is divided into several sub-regions to reduce the Jakobi matrix scale. Secondly, the synchronous phase measurement device is introduced to enrich the state estimation measurement types, improve the accuracy of measurement, and simplify the Jakobi matrix in each sub-region.Finally, through the power distribution system of IEEE33, the validity of the proposed method is verified from the aspects of state estimation accuracy, calculation time and convergence. The results show that the proposed method combines the advantages of network topology partition and phasor measurement unit, and improves the accuracy of state estimation while reducing the time of state estimation.