Question

The rotor of a 4-pole ac generator is wound with a 200 turns coil. If the flux per pole is 5 m Wb and the rotor runs at a speed of 1500 rpm, the rms value of the induced voltage for this ac generator is nearly
1. 140 V
2. 157 V
3. 164 V
4. 222 V

Answer 1

Correct Answer - Option 4 : 222 V

Synchronous speed \({N_s} = \frac{{120f}}{P}\)

\( \Rightarrow 1500 = \frac{{120 \times f}}{4}\)

Frequency = 50 Hz

Induced voltage = 4.44fT_phϕ

= 4.44 × 50 × 200 × 0.005

Induced voltage = 222 V