Consider two buses connected by an impedance of (0 + j5)Ω.

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Consider two buses connected by an impedance of (0 + j5)Ω. The bus 1 voltage is 100 ∠30° V, and bus 2 voltage is 100 ∠0° V. The real and reactive power supplied by bus 1, respectively are

1. 1000 W, 268 VAr
2. – 1000 W, – 134VAr
3. 276.9 W, – 56.7 VAr
4. – 276.9 W, 56.7 VAr

Correct Option: A

P + jQ = VI* = 100 ∠30°		100∠30° - 100∠0°
		5j

= 100 ∠30° {20∠-60 - 20∠- 90°}*
=100 ∠30° {(10 - j17.32) + 20j}*
=100 ∠30° . 10.35 ∠- 15°
= 1035 ∠15° = P + jQ
∴ P = 1035 cos 15 = 1000W
and Q = 1035 sin 15 = 268 VAr.