Short-circuit contribution of induction generators
Short-circuit contribution of induction generators
(OP)
Hi all,
in the case of 1MW hydro powered induction generator, connected to the grid.
I know we should use subtransient reactance (13.3 to 16.7 %), for first cycle contribution, and 1.5xsub. transient reactance for interrupting time contribution (2 to 8 cycles).
My question is: is it correct to consider the contribution equal to 0 passed this point?
What will be the current after 10 or 15 cycles?
I looked in IEEE books and didn't find any infos about this.
Thanks for your answers/comments
JL
in the case of 1MW hydro powered induction generator, connected to the grid.
I know we should use subtransient reactance (13.3 to 16.7 %), for first cycle contribution, and 1.5xsub. transient reactance for interrupting time contribution (2 to 8 cycles).
My question is: is it correct to consider the contribution equal to 0 passed this point?
What will be the current after 10 or 15 cycles?
I looked in IEEE books and didn't find any infos about this.
Thanks for your answers/comments
JL






RE: Short-circuit contribution of induction generators
However, depending on capacitor instalation, it is possible to have some self excitation, but the lower the voltage at the induction generator, the lower it will be.
If you find out something better than what i gave I would like to know, as I will be contending with a few hydro units soon.
RE: Short-circuit contribution of induction generators
RE: Short-circuit contribution of induction generators
You can not ask the question without considering realted factors unless high level answers are required
RE: Short-circuit contribution of induction generators
Let's say the generator has a 500A sub. transient contribution for a line-ground fault at the utiliy's substation. With a current of this magnitude the utility's ground fault protection takes, say 0.25 sec. to operate.
Then, in case of a fault on a adjacent line in the substation, I don't have to worry about the generator contribution to trip the hydroplant line breaker. The generator contribution will decay to 0 long before the relay trips.
JL