A 20-pole alternator is having 180 identical stator slots

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A 20-pole alternator is having 180 identical stator slots with 6 conductors in each slot. All the coils of a phase are in series. If the coils are connected to realize single-phase winding, the generated voltage is V₁. If the coils are reconnected to realize three-phase star -connected winding, the generated phase voltage is V₂. Assuming full pitch, single-layer winding, the ratio V₁ / V₂ is

1. 1
  √3
2. 1
  2
3. √3
4. 2

Correct Option: D

Given poles, P = 20
Total slots = 180
4 Total no. of conductor = 180 × 6 = 1080
4 the ratio of voltage generated when the coils are connected in 1 – φ to when the coils are connected in 3 – φ, Y-connection.

i.e.	(V₁)_{1 – φ}	= 2
	(V₂)_{3 – φ}

	1
	√3