A large coil of wire designed to introduce inductive reactance into a power system. Series reactors limit short-circuit fault currents to levels that circuit breakers can safely interrupt. Shunt reactors connect across transmission lines to absorb reactive power and prevent voltage rise during light load conditions.
We need to switch in the shunt reactor to pull the line voltage down before the evening load drops off completely.
Unlike transformers which transfer power between circuits, reactors are single-winding devices built specifically to oppose changes in alternating current.
Related terms
Reactive power
Power that surges back and forth between the source and the fields of inductors and capacitors, doing no net work.
Impedance
Total opposition a circuit offers to alternating current, combining resistance and reactance, in ohms.
Short circuit
Unintended low-impedance path between conductors at different potentials, bypassing the load.