A three-phase, four-pole induction motor, connected at ∆, 220V, 60Hz, presents rotational losses of 300W when operating with a slip of 2.5%. It is known that the motor has the following parameters per phase: r1 = r2′ = 0.5Ω, x1 = x′2 = 1jΩ, rc = 107Ω xφ = 10jΩ. Under these conditions, calculate: (a) The line current supplied by the mains to the motor. (b) Engine efficiency. (c) Assume the motor starts at a standstill, find the starting line current.

A three-phase, four-pole induction motor, connected at ∆, 220V, 60Hz, presents rotational losses of 300W when operating with a slip of 2.5%. It is known that the motor has the following parameters per phase: r1 = r2′ = 0.5Ω, x1 = x′2 = 1jΩ, rc = 107Ω xφ = 10jΩ. Under these conditions, calculate: (a) The line current supplied by the mains to the motor. (b) Engine efficiency. (c) Assume the motor starts at a standstill, find the starting line current.

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter39: Synchronous Motor Operation

Section: Chapter Questions

Problem 14SQ: Induction motors and welding transformers require magnetizing current, which causes a. lagging power...

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