State Estimation in Three-Phase Unbalanced Low Voltage Grids Using Uncertainty Intervals

Abstract:
Due to the sparse measurement configuration, state estimation in low voltage grids is affected by large uncertainties. An appropriate treatment of uncertainty is thus essential. This paper proposes the usage of uncertainty intervals to model pseudo-measurement errors, which strictly enclose the true value and all possible errors. Modeling the components of three-phase unbalanced low voltage grids and the required extension of the conventional state estimation method is particular scope of this contribution. The proposed concept is finally demonstrated using a real low voltage feeder from a German Distribution System Operator.