Modeling pulse reflections due to multiple discontinuities on electric fence structures

This paper presents a mathematical model through which the propagation characteristics of high voltage (HV) transient pulses along a multi-wire electric fence line that has discontinuities due to loads, faults, and branches, can be accurately predicted. The fence line, which has an earth return path, is modeled in frequency domain to facilitate an analytical solution for the propagation of HV pulses along the line. The discontinuities are modeled by dividing the fence into sections at the discontinuities and representing each section between two discontinuities as an N-port network. The boundary conditions for each section are derived in relations to the other sections and initial conditions to realize a solution in the frequency domain. The frequency domain solution is then transformed into time domain through a numerical Laplace inversion algorithm to determine the propagation characteristics of the line at a given location and time. As confirmed by simulations of power systems computer aided design (PSCAD), the proposed fence model is accurate, and can be considered as an invaluable tool at the design phase of electric fence energizers.