PMU Placement to Reduce State Estimation Bias Considering Parameters Uncertainty

In this paper, a novel analysis is performed to determine the bias of Weighted Least Squares (WLS) power system state estimator to find out how much different placements of Phasor Measurement Unit (PMU) will affect the state estimator’s bias behavior whereas the network parameters are subjected to different quantities of uncertainties for a given measurement uncertainty. The lack of unbiasedness is an important defect of state estimators hence, for each network parameters uncertainty the bias of state estimator is computed. To determine how much the state estimator is biased, using the classical hypothesis test approach a threshold is assigned. The analysis is simulated on IEEE 14-Bus power network test case. To have an idea about the visualization of bias test concept, the bias of voltage magnitude and phase angle errors versus the parameters uncertainty are shown for a PMU placement. Then, for different PMU placements, the values of parameters uncertainty that the state estimator is less biased are shown. The novelty of this analysis is that it finds the location of PMUs to have the state estimator less biased, considering different network parameters uncertainties.