Transformers Inrush above Available S.C.
Transformers Inrush above Available S.C.
(OP)
Looped medium voltage cable system feeds multiple transformers totaling to approximately 21MVA. The voltage is 25kV and utility available short circuit current at the primary gear is about 3kA. My questions is with respect to transient state during momentary source outage.
The 8 to 12 times FLA of all transformers is above the available short-circuit level. My concern is that due to the weak system, the inrush will be limited below the available short circuit level, but the time required for the units to reach steady state could be above the assumed 0.1sec (6-cycles) period. I am just curious to see how some of you have dealt with modeling or solving this issue. My concern is tripping of loop cable protective device upstream of transformers and their protective device. Are there any recommendations or papers on this subject.
The 8 to 12 times FLA of all transformers is above the available short-circuit level. My concern is that due to the weak system, the inrush will be limited below the available short circuit level, but the time required for the units to reach steady state could be above the assumed 0.1sec (6-cycles) period. I am just curious to see how some of you have dealt with modeling or solving this issue. My concern is tripping of loop cable protective device upstream of transformers and their protective device. Are there any recommendations or papers on this subject.
"Throughout space there is energy. Is this energy static or kinetic! If static our hopes are in vain; if kinetic — and this we know it is, for certain — then it is a mere question of time when men will succeed in attaching their machinery to the very wheelwork of nature". – Nikola Tesla






RE: Transformers Inrush above Available S.C.
RE: Transformers Inrush above Available S.C.
"Throughout space there is energy. Is this energy static or kinetic! If static our hopes are in vain; if kinetic — and this we know it is, for certain — then it is a mere question of time when men will succeed in attaching their machinery to the very wheelwork of nature". – Nikola Tesla
RE: Transformers Inrush above Available S.C.
RE: Transformers Inrush above Available S.C.
"Throughout space there is energy. Is this energy static or kinetic! If static our hopes are in vain; if kinetic — and this we know it is, for certain — then it is a mere question of time when men will succeed in attaching their machinery to the very wheelwork of nature". – Nikola Tesla
RE: Transformers Inrush above Available S.C.
RE: Transformers Inrush above Available S.C.
"Throughout space there is energy. Is this energy static or kinetic! If static our hopes are in vain; if kinetic — and this we know it is, for certain — then it is a mere question of time when men will succeed in attaching their machinery to the very wheelwork of nature". – Nikola Tesla