Calculate the equivalent resistance between A & B using star-delta conversion

Calculate the equivalent resistance between A & B using star-delta conversion
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Answer :

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Solution : 

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Converting Inner star in to delta- 


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Resistances 4 and 6 are in parallel in all branch so


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A 4000 kVA, 11 kV/132 kV delta-star connected 3-phase transformer has reactance, x1 = 0.12 p.u.

Description : A 4000 kVA, 11 kV/132 kV delta-star connected 3-phase transformer has reactance, x1 = 0.12 p.u. The actual value of x1 referred to the low voltage side is (A) 0.85 Ω (B) 3.63 Ω (C) 36.3 Ω (D) 252 Ω

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