Uncertainty analysis of power system state estimates and reference bus selection

• The estimation quality may vary depending on the reference bus considered.
• A procedure to determine the optimal location of the reference bus is proposed.
• The 118-bus and 300-bus IEEE systems studied and the results are analyzed.
• The proposed technique is computationally efficient and numerically accurate.
• The developed algorithm is robust against perturbations.

The state estimation (SE) in an electric power system is subject to uncertainty, due to random measurement errors, inaccurate line parameters, etc. Specifically, the location of the reference bus may influence over the accuracy of some estimated states. This paper analyzes this effect and proposes an algorithm to select the reference bus, pursuing maximum overall accuracy. Two realistic case studies are analyzed and conclusions duly drawn.