Back Energisation relay

[kssschsekhar]

What is the purpose of Back Energisation relay for generator transformer (61 MVA, 220/11.5kv,Ynd11)protection?

Relay used is CAG37, make: GEC Alstom.

 

[davidbeach]

If that is what I know as an inadvertent energization relay, it is to avoid the disaster that happens when a generator that is not at synchronous speed is inadvertently connected to the system.

 

[kssschsekhar]

Can you please elaborate more on this topic. If possible can you please send the literature/ web site name for furthur information on this topic

 

[davidbeach]

Have you tried entering "inadvertent energization" into google?

 

[RRaghunath]

Back energisation is not same as Inadvertant energisation as we use in India. Back energisation refers to energising the generator transformer from HV side with generator connection (or Generator LVCB, if relevant) open.

The relay CAG 37 is Instantaneous OC relay, used for short-circuit protection. In this case, the relay can protect the system in case of faults on the HV side of the transformer, including the bushings and cable / overhead line.

Trust the above helps.