GSU Transformer
GSU Transformer
(OP)
Hello,
I am putting together a specification for a 115/2400 GSU transformer and I was wondering if anyone on here may know if this type of transformer should follow IEEE Std. C57.116-2014: IEEE Guide for Transformers Directly Connected to Generators? Also, what is the difference between normal substation transformers and GSU transformers? From my understanding, the GSU Transformers experience much more thermal stress. I have heard that they may should be wye-delta connected??? Should anything different be stated in the GSU spec that is not in a normal transformer spec?
Any feedback and information will be appreciated.
Thank you!
I am putting together a specification for a 115/2400 GSU transformer and I was wondering if anyone on here may know if this type of transformer should follow IEEE Std. C57.116-2014: IEEE Guide for Transformers Directly Connected to Generators? Also, what is the difference between normal substation transformers and GSU transformers? From my understanding, the GSU Transformers experience much more thermal stress. I have heard that they may should be wye-delta connected??? Should anything different be stated in the GSU spec that is not in a normal transformer spec?
Any feedback and information will be appreciated.
Thank you!






RE: GSU Transformer
There could be many other aspects, which I do not readily recall.
RE: GSU Transformer
RE: GSU Transformer
RE: GSU Transformer
http://GeneralPAC.com - Awesome video tutorials for power systems PAC!
The Wye Wye Transformer Connection video: http://gpac.link/1GdGRSQ
RE: GSU Transformer
'Generously rated' in relation to the turbine rating - gas turbines like cold dry air, so it is possible for a machine to produce more output than its nameplate rating at standard conditions. Turbine capability rises faster than transformer capability as temperature drops, and most operators don't want their turbine constrained by the transformer capability so the transformer is typically 10% larger in rating than the alternator it is coupled to.
'Heavily braced' is usually necessary due to the very high assymetric peak currents during a fault close to the generator which imposes maximum stress on the bracing. Generator subtransient reactance isn't all that large in terms of limiting the fault, plus in a multi-machine station there is a lot of infeed from both the grid and neighbouring units without much system impedance to calm things down.
RE: GSU Transformer
May you grow up to be righteous, may you grow up to be true...
RE: GSU Transformer
RE: GSU Transformer
RE: GSU Transformer
That is one part of GSU range.Otherwise it is less than alternator rating as part of power will be taken by auxiliaries. Some special requirements will be there for GSUs for pumped storage hydro stations, or units with generator circuit breakers.
A 3L fault on GSU primary or generator terminals is remote as the connections are of isolated phase bus duct.
Transformer engineers believe that transformers designed with a core flux density of 1.7 T at rated voltage and frequency will withstand 110 % overfluxing continuously, 125 % for 1 minute and 140% for 5 sec. No one has tested it though. These are the extent of overfluxing noticed in thermal power stations with large generators and GSU specifications normally call for this range of overflux with stand capability.
RE: GSU Transformer
May you grow up to be righteous, may you grow up to be true...