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short circuit torque

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gaux

Mechanical
Joined
Jan 27, 2009
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48
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TR
I have a asyncronous generator 500 kw and 500 rpm speed, and i´´m designing a fly wheel for it, and the short circuit torque given by the manufacturer is 96 KNm, and i think that maybe is too much... how could i know if this is true..or no so true.... does somebody could help me.... I´´m not very confortable with this questions.... thanks.
 
You need to use the value given by the manufacturer, unless you have a lot of liability insurance.

You might ask them to verify, but in the end, you must use their value.
 
but in your opinions, what do you think? is too much?? and why it could be a high value..?
what are the elements that make it to be high? reactance?
thanks
 
I agree with dpc you have to follow the Manufacturer indications.
For a very rough appreciation let's take as follows:
Prime motor [DG or wind or else] rated torque as Generator rated torque: Trated= 60*1000/2/PI()*P/rpm=9549.3 Nm.
For a similar induction motor the inertia moment will be J= 60 Kg.m^2.Let's say the prime motor has the same inertia moment.
Let's suppose, up to generator breaker will trip time=0.07 sec and within this time the generator will positively stop.
The possible torque on the Generator shaft will be Te=(Jgen+Jmot)dw/dt+Trated
dw=(2*pi*rpm/60-0)= 52.36 rot/sec
Te=2*60*52.36/.07+9549.3=102000 Nm=102 kNm.
 
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