With the expanding scale of the power system

the distributed state estimation is one of the effective ways to overcome the difficulties of the centralized state estimation

such as too high calculation dimensions and large measurement data processing. This paper adopts the Cabuture Kalman filter to do the local estimation

and employs the least square estimation fusion to coordinate the estimates of the boundary bus states in the coordination center. According to the coordinated estimates of the boundary bus states

each subarea can further correct the local estimates of the internal bus states through the Kalman filter algorithm. Finally

the simulation results show that the estimated precision of the proposed method is close to the centralized method

and the proposed method has a better real-time property. Moreover

the proposed method only need less communication data

which is easy to be implemented.This work is supported by National Natural Science Foundation of China(No. 51177049)and National Science Funds for Excellent Young Scholars of China(No. 51322702).