A voltage source inverter is used to control the speed of a three-phase, 50 Hz squirrel cage induction motor. Its slip for rated torque is 4%. The flux is maintained at rated
value. If the stator resistance and rotational losses are neglected, then the impressed voltage to obtain twice the rated torque at starting should be

A

10 Hz

B

5 Hz

C

2 Hz

D

4 Hz