Question

Synchronous-induction coupled motors are required for ____________

(a) high starting torque applications

(b) high pull out torque applications

(c) high running torques applications

(d) none of the mentioned

I have been asked this question in an interview for internship.

The origin of the question is Machine Applications in division Electrical Machine Applications/Armature Reaction and Commutation of Electrical Machines

Answer 1

Right answer is (a) high starting torque applications

To elaborate: Induction motor provides high starting torque with proper values of slip ring terminal resistance. Coupled along with the synchronous motor it acts as an independent set and be employed in high torque application.