Abstract
The paper discusses an optimal placement for UPFCs and an optimal method for the selection of global measurements in a wide-area controlled network for the purpose of damping power system oscillations. Both the placement and signal selection methods are optimized to damp interarea oscillations. Optimal UPFC placement is identified by comparing different candidate placements based on the total damping they produce. Optimal selection of output measurements is based on the projection of the right eigenvectors on outputs. After the selection of the desired output measurements, observer gains are designed by LMI approaches. Test results from the IEEE 57 bus test system indicate good potential in terms of selecting UPFC placements and output signals.