Abstract: In view of the characteristics of radial distribution,weak loop operation and lack of real-time measurement of distribution networks with distributed photovoltaics,the paper proposes to expand the state estimator measurement by means of partial key node configuration PMU measurement and PV active output prediction.Using the collinearity test method based on the standardized Lagrangian multiplier,the PMU measurement node is configured to decompose the system,and the centralized state estimation is decomposed into two parts:sub-partition state estimation and coordination side state estimation.Network area distributed computing.Finally,the accuracy and superiority of the article proposed method are verified by the simulation test of the system.