For complex power transfer interfaces or load areas with multiple in-feeds, we present a method for phasor-measurement-based calculation of voltage stability margins. In the case of complex transfer paths with multiple injections, a radial system approach may not be sufficient for voltage stability analysis. Our approach provides voltage stability margins considering the full fidelity of the transfer paths. In this paper, we extend a previously proposed phasor-measurement-based approach and apply it to a voltage stability-limited power transfer interface using synchronized phasor measurements from loss-of-generation disturbance events. Previous work employed a simple radial system or modeled a power transfer interface using only one generator. In our approach, we use the PMU data to model multiple external injections that share the power transfer increase, and we employ a modified AQ-bus power flow method to compute the steady-state voltage stability margins. We demonstrate the method using real PMU data from disturbance events in the US Eastern Interconnection.

%B 2014 Power Systems Computation Conference (PSCC) %I IEEE %C Wrocław, Poland %P 1 - 6 %8 08/2014 %R 10.1109/PSCC.2014.7038431 %0 Report %D 2014 %T PMU Location and Study Region Selection %A Joe H. Chow %A Scott G. Ghiocel %K AA13-001 %K synchrophasor applications %K synchrophasors %K voltage stability %B Voltage Stability Applications using Synchrophasor Data %I Rensselaer Polytechnic Institute %8 01/2014 %0 Report %D 2013 %T Development of the Voltage Stability Analysis Framework %A Joe H. Chow %A Scott G. Ghiocel %K AA13-001 %K synchrophasor applications %K synchrophasors %K voltage stability %B Voltage Stability Applications using Synchrophasor Data %I Rensselaer Polytechnic Institute %8 12/2013 %0 Report %D 2013 %T State-of-the-Art Voltage Stability Analysis Survey %A Joe H. Chow %A Scott G. Ghiocel %K AA13-001 %K synchrophasor applications %K synchrophasors %K voltage stability %B Voltage Stability Applications using Synchrophasor Data %I Rensselaer Polytechnic Institute %8 03/2013 %0 Report %D 2013 %T Voltage Stability Applications using Synchrophasor Data: Reports 6, 7, and 8 %A Joe H. Chow %A Liehr, Maximilian %A Felipe Wilches-Bernal %K AA13-001 %K synchrophasor applications %K voltage stability %X This combined progress report includes the following: Report 6: Perform Voltage Stability Analysis Report 7: Development of Network Models for Wind Generation Sites Report 8: Real-Time Application Strategies %B Voltage Stability Applications using Synchrophasor Data %I Rensselaer Polytechnic Institute %8 12/2013 %0 Journal Article %J European Transactions on Electrical Power %D 2011 %T Transmission line parameter identification using PMU measurements %A Di Shi %A Daniel J. Tylavsky %A Koellner, Kristian M. %A Logic, Naim %E Joe H. Chow %K AARD %K phasor measurement units (PMUs) %K RM11-005 %X Accurate knowledge of transmission line (TL) impedance parameters helps to improve accuracy in relay settings and power flow modeling. To improve TL parameter estimates, various algorithms have been proposed in the past to identify TL parameters based on measurements from Phasor Measurement Units (PMUs). These methods are based on the positive sequence TL models and can generate accurate positive sequence impedance parameters for a fully transposed TL when measurement noise is absent; however, these methods may generate erroneous parameters when the TLs are not fully transposed or when measurement noise is present. PMU field-measure data are often corrupted with noise and this noise is problematic for all parameter identification algorithms, particularly so when applied to short TLs. This paper analyzes the limitations of the positive sequence TL model when used for parameter estimation of TLs that are untransposed and proposes a novel method using linear estimation theory to identify TL parameters more reliably. This method can be used for the most general case: short/long lines that are fully transposed or untransposed and have balanced/unbalance loads. Besides the positive/negative sequence impedance parameters, the proposed method can also be used to estimate the zero sequence parameters and the mutual impedances between different sequences. This paper also examines the influence of noise in the PMU data on the calculation of TL parameters. Several case studies are conducted based on simulated data from ATP to validate the effectiveness of the new method. Through comparison of the results generated by this novel method and several other methods, the effectiveness of the proposed approach is demonstrated. %B European Transactions on Electrical Power %V 21 %P 1574 - 1588 %8 05/2011 %N 4 %! Euro. Trans. Electr. Power %R 10.1002/etep.522