Fault Location on Transmission Lines considering Parameter Variations
and Current Transformer Saturation
Abstract
The fault location on a transmission line plays a very important role in
power system operation. The accurate and fast fault location results on
the transmission lines are particularly important in minimizing
operating costs and maximizing power system reliability. In this paper,
the fault location problem is proposed to transform into the
optimization problem solved by optimization algorithms. It is realized
that most fault location procedures highly depend on transmission line
parameters which are always time-varying under various operation
conditions. The inaccuracy of the transmission line parameters greatly
affects the fault location results. Thus, these parameters are proposed
to estimate for variations. Moreover, when faults occur near the
transmission line terminals, the fault currents are high. Then, a
current transformer (CT) saturation and a secondary current distortion
happen in the transmission system also affecting the accuracy of the
fault location results. Instead of measuring the currents affected by
the CT saturation, the currents are proposed to estimate for inputting
the fault location procedure. In this paper, advanced artificial bee
colony (ABC) algorithms are proposed to estimate the parameters and
currents at the two terminals of the transmission line; and finally,
locate faults on the transmission lines. The advanced ABC algorithms are
the variants of the ABC algorithm proposed to improve its exploitation
ability. This results in the enhancement of the convergence value and
reduction of the iterations required. The numerical results and
comparisons confirm the effectiveness of the proposal.