A 3-phase, 400 V, 4 pole, 50 Hz star connected induction motor has the following parameters referred to the stator:
\( R_r' = 1 \, \Omega \), \( X_s = X_r' = 2 \, \Omega \)
Stator resistance, magnetizing reactance and core loss of the motor are neglected.
The motor is run with constant \( V/f \) control from a drive. For maximum starting torque, the voltage and frequency output, respectively, from the drive, is closest to: