Line parameter estimation using phasor measurements by the total least squares approach

Transmission line parameters can be estimated from PMU data at the end of two lines. Both linear least squares and total least squares approaches have been suggested in the literature. This paper further develops the TLS approach for estimating positive sequence line parameters. We present an algorithm for appropriate selection of phasor samples (similar to down sampling) so as to contain independent information for better filtering action. Results of parameter estimation will be erroneous if the CVT accuracy is compromised. We propose a Durbin Watson test to detect serial correlation in errors to flag biased CVT measurements. Finally, we compare and contrast TLS and LS estimators and demonstrate superiority of TLS approach using ATP-EMTP simulations.