Reference:
J. Fu,
G. Song, and
B. De Schutter,
"Influence of measurement uncertainty on parameter estimation and
fault location for transmission lines," IEEE Transactions on
Automation Science and Engineering, vol. 18, no. 1, pp. 337-345,
Jan. 2021.
Abstract:
Fault location algorithms for transmission lines use the parameters of
the transmission line to locate faults after the faults have occurred
along the line. Although these parameters can be estimated by the
phasor measurement unit(s) (PMU(s)) at the terminal(s) of the
transmission line continuously, the uncertainty in the measurements
will give rise to stochastic errors in the measured values. Thus, the
uncertainty in measurements definitely influences the estimations of
the parameters of the transmission line, which in its turn influences
the results of fault location algorithms. Inaccurate results of fault
location algorithms may lead to costly maintenance fees and prolonged
outage time. Therefore, in this paper, we estimate the parameters of
the transmission line considering the uncertainty in the measurements
so that a more accurate fault location can be derived. The uncertainty
in the measurements will be modeled as a stochastic distribution and
the maximum likelihood estimation (MLE) method will be adopted to
reduce the uncertainty in the measurements. In addition, as an
illustration, the telegrapher's equations will be used to calculate
the parameters of the transmission line and the two-terminals positive
sequence network fault location algorithm will be used to locate the
fault. In a simulation case study of a real-life transmission line the
influence of the uncertainty in the measurements on the transmission
line parameter estimations and the effectiveness of the MLE method for
estimations are simulated and analyzed. The results show that the
influence of the uncertainty in the measurements on the positive
sequence network fault location algorithm should not be neglected and
that the proposed method is very effective in significantly reducing
the influence of the uncertainty in the measurements.