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For a given 4-pole machine, carrying armature current 56.82 A, with 846 conductors. The mean flux density in the air gap under the interpoles is 0.5 Wb/m2 on full load and radial gap length is 0.3 cm. Ampere-turns required for an interpole is ____________

For a given 4-pole machine, carrying armature current 56.82 A, with 846 conductors. The mean flux density in the air gap under the interpoles is 0.5 Wb/m2 on full load and radial gap length is 0.3 cm. Ampere-turns required for an interpole is ____________ Correct Answer 4198

Required ampere-turns are given by ATi = ATa (peak) +(Bi/µ0 )lgi . Substituting the ATi = +(0.5/4π*10-7 )* 0.3*10-2 =4198. Turns can be found by dividing with armature current.

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