A distribution feeder of 1km length having resistance, but

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A distribution feeder of 1km length having resistance, but negligible reactance, is fed from both the ends by 400V, 50Hz balanced sources. Both voltage sources S₁ and S₁ are in phase. The feeder supplies concentrated loads of unity power factor as shown in the figure.

The contributions of S₁ and S₂ in 100A current supplied at location P respectively, are

1. 75A and 25A
2. 50A and 50A
3. 25A and 75A
4. 0A and 100A

Correct Option: D

Let I be current supplied by source – 1
‘r’ be resistance/length
400 = (400r) I + (200r) (I – 200) + (200r) (I – 300) + (200r) (I – 500) + 400
∴ 0 = 400rI + 200rI – 40000r + 200rI – 60000r + 200rI – 100000r
∴ 100Ir = 20000r
∴ I = 200A
Current in branch – B is I – 200 = 200 – 200 = 0
4 point p
source – 1 supplies 0A current
source– 2 supplies 100 A current