Question

What happens to the current in the windings during the sudden short circuits at the line terminals?

(a) the current reduces to 15 times the full load current

(b) the current increases to 15 times the full load current

(c) the current reduces to 10 times the full load current

(d) the current increases to 10 times the full load current

I have been asked this question in final exam.

Asked question is from Construction of Hydro-Generators in chapter Design of Synchronous Machines of Design of Electrical Machines

Answer 1

Right answer is (b) the current increases to 15 times the full load current

For explanation I would say: The current in the windings during short circuit at the line terminals increases to about 15 times the full load current. It can also increase to higher level depending on the direct axis sub-transient reactance.