Assume that a 50-Hz, 50-kVA, star-delta transformer bank of vector group Yd11 is accidentally paralleled with...

Assume that a 50-Hz, 50-kVA, star-delta transformer bank of vector group Yd11 is accidentally paralleled with a 50-Hz, 50-kVA, star-star transformer bank of vector group Yy0. Both have a bank ratio of 2000/200-V. The equivalent impedances referred to the respective secondaries are ZΔ = 0.1106/60.2° Ω and ZY = 0.0369/60.2° Ω. (a) Assuming the load switch to be open, draw the connection diagram (3.0 marks). (b) Determine the magnitude of the current circulating in each transformer secondary (15.0 marks). (c) Express the current in (b) as a percent of the rated transformer current for each transformer (2.0 marks). Use the method of mesh analysis applied to the three-phase circuits (marks will not be awarded for using the single-phase equivalent method). show all your steps

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Manojponduru answered 2 years ago

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