CTs in isophase bus ducts
CTs in isophase bus ducts
(OP)
how are the CTs mounted installed in the isophase bus ducts? my thought is to provide a transition compartment where the CTs are mounted thru the bus.
i am not in practice with MV power generation so I cannot visualize this situation.
thanks for your comments.






RE: CTs in isophase bus ducts
RE: CTs in isophase bus ducts
This may not directly address your question, but alternatives are described in IEEE Std C37.102-1995 …AC Generator Protection, it seems that use of generator- and GSU-transfomer-mounted CTs may be suitable for bus protection, and possibly more cost-effective compared to isophase-bus mounting. Two schemes are described.
87U Differential relay for overall unit and transformer.
87T Differential relay. Primary protection for the GSU or UAT transformer. May be used to provide phase fault backup for the generator in some station arrangements. The zone may be extended to cover the generator bus using cts from the generator and Unit Auxiliary Transformer when lowside cts are not available.
RE: CTs in isophase bus ducts
Busbar's comments represent typical practice on IPBs associated with large generator conenctions to their associated step-up grid transformers. The is always a discontinuity at the end of an IPB, so introducing a CT there does not further degrade the performance. You also have more chance of getting access to a CT mounted in a bushing cubicle than one installed mid-way along an IPB.
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RE: CTs in isophase bus ducts
thanks again to all the postings! gives me valuable info.