ABSTRACT
Shunt reactors are used to control VAR loading. Series reactors are used to reduce short-circuit current by increasing impedance or to control power flow by changing transmission-line impedance.
Differential relays are used to detect failures quickly and to initiate isolation of failed oil-filled reactors and air-core shunt reactors. Tank sudden pressure relays may be used to provide an alternate means of detecting failures. Overcurrent or impedance relays can be used to provide backup protection. Air-core series reactors are usually considered to be in the zone of protection provided for the associated transmission line, distribution line, or transformer.
