Induction motor fault current contribution vs motor load
Induction motor fault current contribution vs motor load
(OP)
I was always under the impression that the asymmetrical current contribution of an induction motor to a system fault is due to the stored energy in the magnetic field between the rotor and stator (airgap flux). The way I see it this does not depend on the motor load, so whether a motor is 80% or 10% loaded the fault contribution is essentially the same.
Maximum fault contribution is given by LRA/FLA ~ 6p.u.
Is this correct?
Thanks.
Maximum fault contribution is given by LRA/FLA ~ 6p.u.
Is this correct?
Thanks.






RE: Induction motor fault current contribution vs motor load
I may be wrong but my understanding is that the frequency must drop before the motor makes a contribution. But, stored magnetic energy and regeneration may both be factors.
Bill
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"Why not the best?"
Jimmy Carter
RE: Induction motor fault current contribution vs motor load
"Will work for (the memory of) salami"
RE: Induction motor fault current contribution vs motor load
I am quite certain that the motor load at time of fault does not affect the contribution of the motor to the fault but am open to other insights on this.
Regards.
RE: Induction motor fault current contribution vs motor load
It's good to keep in mind that nearly all of the circuit analysis that is done in power engineering involves a lot of simplifying assumptions. The accuracy is sufficient for our purposes. It will never be "exact" unless we want to start from Maxwell's equations every time.
RE: Induction motor fault current contribution vs motor load