Synchrophasor Applications in Power Systems Operation

Abstract

The Phasor Measurement Unit (PMU) is considered to be one of the measuring devices for delivering the vision of smart transmission grid operation due to its ability of enabling faster sampling and accurately extracting phasor information. This thesis investigated aspects of two power system transmission applications enabled through PMU infrastructure: Oscillation Monitoring and State Estimation applications. Many modal analysis algorithms have been proposed based on the implementations of PMU and advanced computation technology. However, bad parameter tuning or sampling at inappropriate intervals, though satisfying Nyquist -Shannon Criterion, can result into inaccurate estimation of oscillating frequencies and their associated damping factors. Hence, the first part of the thesis introduced an optimal parameter tuning procedure and investigated simulated annealing rules for selecting the optimal sampling interval for Prony analysis and Kalman filter . Sequential Monte Carlo simulations were proposed to assess the adequacy of WAMS sampling. In addition, a review of power system oscillations and its detect ion using Prony analysis and Kalman filter was also presented. The second part of the thesis focused on the application of PMUs for power system state estimation. Two specific algorithms that include phasor measurements in WLS state estimator were reviewed. Due to the high capital cost of PMUs, an appropriate methodology for optimal placement of PMUs for complete observability of a power system under normal operation was presented. The application of this method has been demonstrated using the IEEE 14-bus test system.