A New Algorithm for Distributed Power System State Estimation Based on PMUs

In order to implement a functional control scheme for a system, the current state of the system must be known. Otherwise, even the most complicated control system will be handicapped. State estimate is a well-known function in transmission network analysis. In this paper, based on the placement of phasor measurement units (PMUs), a new algorithm for distributed power system state estimation is presented. In the first part of this algorithm, with the placement of PMUs based on the improved method of bordered block diagonal form (BBDF), the large system can be divided into many small systems. In the second part, Using the data of PMUs between subsystems as boundary condition, the problem of distributed power system state estimation with weighted least square turns to the optimization problem with equality constraint. At last, the effectiveness of the proposed algorithm is verified with numerical simulation on 6-machine 25-bus power system, and the computational speed is fast and the result is accurate.