I haven't had much if any experience with protective relays. Can someone explain what directional relays are typically used for?
I haven't had much if any experience with protective relays. Can someone explain what directional relays are typically used for?
This type of relay operates in on direction of current flow and blocks in the opposite direction. Three conditions must be satisfied for its operation: current magnitude, time delay and directionality. The directionality of current flow can be identified using voltage as a reference of direction.
Directional relays are commonly used to protect against generator motoring, such as preventing excess power flow from a small generating station into a larger system. They can also be used to protect systems with networks and/or closed bus ties.
Check out this cutsheet for a GE ICW power directional relay, it gives a good overview of it's theory and various applications. https://www.gedigitalenergy.com/prod...chures/icw.pdf
Last edited by SecondGen; June 25, 2015 at 07:15 PM.
GE's Art & Science of Protective Relay
downloadable PDF
http://www.gedigitalenergy.com/multi...sci/artsci.pdf