Synchronized Phasor Measurements in a Dual Layer Hybrid State Estimator

Original scientific paper The architecture of the proposed Dual Layer Hybrid State Estimator starts with the linear state estimator that only takes synchrophasors as inputs and calculates states of the buses with the deployed Phasor Measurement Units (PMUs) and their adjacent buses. These states are used to obtain the pseudomeasurements that are processed together with conventional SCADA measurements. As the relationship between the conventional measurements and the state variables is nonlinear, in this layer the iterative weighted least squares method is applied to estimate state of the complete power system. The developed formulation was tested on the IEEE systems as well as on the Croatian transmission power system model. The obtained results are compared with the classical solution that uses the conventional measurements and with another hybrid model. The hybrid state estimator based on the proposed architecture offers more accurate state estimation with enhanced filtering of measurements errors and with improved convergence capabilities.