Which of the following equation represents the reluctance torque of a salient pole synchronous machine?(a) Te(av) = 1/4 Im^2(Ld-Lq)sin2δ(b) Te(av) = 2 Im^2(Ld-Lq)sinδcosδ(c) Te(av) = 1/8 Im^2(Ld-Lq)(d) Te(av) = 1/8 Im^2(Ld-Lq)sin2δThe question was asked during an internship interview.This interesting question is from Elementary Synchronous Machines topic in chapter Basic Concepts in Rotating Machines of Electrical Machines

Which of the following equation represents the reluctance torque of a

1.	Which of the following equation represents the reluctance torque of a salient pole synchronous machine?(a) Te(av) = 1/4 Im^2(Ld-Lq)sin2δ(b) Te(av) = 2 Im^2(Ld-Lq)sinδcosδ(c) Te(av) = 1/8 Im^2(Ld-Lq)(d) Te(av) = 1/8 Im^2(Ld-Lq)sin2δThe question was asked during an internship interview.This interesting question is from Elementary Synchronous Machines topic in chapter Basic Concepts in Rotating Machines of Electrical Machines
Answer» The CORRECT CHOICE is (d) Te(AV) = 1/8 Im^2(Ld-Lq)sin2δ To elaborate: Te(av) = 1/8 Im^2(Ld-Lq)sin2δ+1/2 IfImMmaxsinδ If field current If is REDUCED to ZERO, the reluctance torqueTe(av) = 1/8 Im^2(Ld-Lq)sin2δ.

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