Abstract
This paper presents the behaviour of the distance
protection relays on a series compensated transmission line
under fault conditions. Series compensation presents distance
protection elements with unorthodox line impedance and as a
result the relays may operate incorrectly. Sub-harmonic
oscillations and non-linearity of the line impedance are some of
the challenges introduced by series compensation of transmission
lines. The study is carried out in a Digsilent power factory
environment and results pertaining to the response of the
distance relay on a 400 kV series compensated line under fault
conditions are presented