The reactance relay is a fast relay. This relay comprises of two components an overcurrent component and a present voltage directional component. The present component created positive torque and a present voltage created directional component which contradicts the present component relying upon the stage point amongst current and voltage.
Reactance relay is an overcurrent relay with directional constraint. The directional component is masterminded to create greatest negative torque when its present slack behinds its voltage by 90°. The induction cup or twofold induction loop structures are most appropriate for impelling reactance type distance relays.
In this way the reactance type distance relay needs a directional unit that is out of commission under load conditions. Reactance type relay is exceptionally reasonable as a ground relay for ground blame since its compass isn't influenced by fault impedance.
Because ground resistance can be so variable, a ground distance relay must be practically
unaffected by large variations in fault resistance. Consequently, reactance relays are
generally preferred for ground relaying.
For phase-fault relaying, each type has certain advantages and disadvantages. For very
short line sections, the reactance type is preferred for the reason that more of the line can
be protected at high speed. This is because the reactance relay is practically unaffected by
arc resistance which may be large compared with the line impedance, as described
elsewhere in this chapter. On the other hand, reactance-type distance relays at certain
locations in a system are the most likely to operate undesirably on severe synchronizing
power surges unless additional relay equipment is provided to prevent such operation.*##**##*
