Question

A three phase induction motor is connected to 400V, 50 hz supply. If the stator to rotor turn ratio is 2, the standstill rotor induced voltage per phase is?

(a) 115.5 V

(b) 231 V

(c) 346 V

(d) 200 V

I had been asked this question during an interview for a job.

The query is from Rotor EMF, Current and Power in division Induction Machines of Electrical Machines

Answer 1

Right choice is (a) 115.5 V

To elaborate: Emf at secondary per phase = (400/1.73)/2 = 115.47 V.