A New Decomposition and Coordination Algorithm for State Estimation in Interconnected Power System

A new distributed state estimation approach based on decomposition and coordination is presented to solve the state estimation(SE) of interconnected multi-area power grid.According to the weighted mean of power residual error obtained by SE of subsystems at both ends of virtual buses,the computation center of interconnected power grid calculate the varying quantities of injected power in each several virtual buses of subsystems.By means of the sensitivity matrix of nodal state variables to the injected power of subsystems and that of estimated power value to nodal state variables,the SE results of subsystems are modified to obtain the solution of SE for interconnected power grid.Simulation results show that the distributed SE algorithm is an accurate and fast approach for SE of interconnected power grid,and can calculates partial observable results of interconnected power grid maximally and accurately when the computation center cannot obtain data of partial subsystems.