Relay is Used for Busbar Applications

Hi,

Busbar Protection schemes are widely used in EHV, UHV as well as in critical HV systems. These will detect the faults in busbar and act very fast to trip all the feeders connected with the faulty bus. Bus bar differential protection are widely used for this kind of protection and in case, if you have double bus bar systems, when a fault occurs in Bus-A, all the feeders connected to Bus-A will be tripped without interrupting other feeders connected in healthy bus. Bus bar protection relays will be getting the current input from all the incomers and outgoing feeders which all connected to the protected bus. According to kirchoff law, incoming current= outgoing current. So if any fault occurs in the bus, incoming current will be higher than outgoing. So the relay will sense the difference and trips.

Hope it helps!

-Vijay

thanks for your reply. but i do not understand yet because as you told relay will trip if one of busbars be fault and relay will only trip busbars that be fault and two of busbars still operate normally but the three phase motor will not operate if the system only have two healthy phases, I do not understand this problem that you told me

oh my man.. I think you are basically from electrical background. Bcoz 'bus ' means it always comprises three phases. kindly go through the basic electrical designs of substations.

Yes! Io agree with Vijay. Bus 'A' means R, Y & B Phase Bus bars in Bus Section 'A' and Bus 'B' means R, Y & B Phase Bus bars in Bus Section 'B'.

By the by, just to share with you, why a BUS is called a BUS?

It is derived from the Latin Word "Omnibus" meaning Universal Conveyance. (True with public transportaion too, you know!).

I thank to Vijay. I understand this problem. I think I must learn more things