Q1) A 460-V, 25-hp, 60-Hz, four-pole, Y-connected induction motor has the following impdances in ohms per phase referred to the stator circuit: R1 = 0.641 Q, X1 = 1.106 N, R2'=0.332 N, X2' = 0.464 2, Xo = 26..3 Q The total rotational losses are 1100 Wand are assumed to be constant. The core loss is Jumped in with the rotational losses. For a rotor slip of 2.2 percent at the rated voltage and rated frequency, find the motor's 1) Input current & Efficiency 2) Sketch the complete torque-speed characteristic of an induction machine and indicate the three modes of oneration

Q1) A 460-V, 25-hp, 60-Hz, four-pole, Y-connected induction motor has the following impdances in ohms per phase referred to the stator circuit: R1 = 0.641 Q, X1 = 1.106 N, R2'=0.332 N, X2' = 0.464 2, Xo = 26..3 Q The total rotational losses are 1100 Wand are assumed to be constant. The core loss is Jumped in with the rotational losses. For a rotor slip of 2.2 percent at the rated voltage and rated frequency, find the motor's 1) Input current & Efficiency 2) Sketch the complete torque-speed characteristic of an induction machine and indicate the three modes of oneration

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter33: Four-speed, Two-winding (consequent Pole) Motor Controllers

Section: Chapter Questions

Problem 7SQ: Why are different motor connections shown for what appears to be the same motor in the various...

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59 ۱۱:۶۳ ص | ۲۰۰۸ك.بث | A 460 V.pdf A 460 V, 60 Hz, Star connected, 870 r.p.m., Eight poles, Three-Phase Induction Motor has the following per phase parameters: R1 = 0.07, R2 = 0.05, X1 = X2 = 0.2, Xm = 6.5, Draw the approximate equivalent circuit and determine the following: 1. III. IV. V. VI. VII. Starting Torque Maximum Torque Rated Torque Stator Current Power Factor Input Power Magnetizing Current †
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