A 460-V, 25-hp, 60-Hz, four pole, Y-connected induction motor has the following impedances in ohms per phase referred to the stator circuit: R1 = 0.641N R2 = 0.3320 X1 = 1.1060 X2 = 0.4640 XM = 26.30 The total rotational losses are 1100 W and are assumed to be constant. The core loss is lumped in with the rotational losses. For a rotor slip of 2.2 % at the rated voltage and rated frequency, find the motor's a) Speed b) Stator current c) Power factor d) Peony and Pout e) Tind and Toad f) Efficiency

A 460-V, 25-hp, 60-Hz, four pole, Y-connected induction motor has the following impedances in ohms per phase referred to the stator circuit: R1 = 0.641N R2 = 0.3320 X1 = 1.1060 X2 = 0.4640 XM = 26.30 The total rotational losses are 1100 W and are assumed to be constant. The core loss is lumped in with the rotational losses. For a rotor slip of 2.2 % at the rated voltage and rated frequency, find the motor's a) Speed b) Stator current c) Power factor d) Peony and Pout e) Tind and Toad f) Efficiency

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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A three-phase induction motor, operating at rated voltage and frequency, has a startingtorque of 1.35 times and a maximum torque of 2.2 times, both with respect to its rated-loadtorque. Ignoring the effects of the stator resistance and rotational losses and assumingconstant rotor resistance, determine the slip at the maximum torque;
a. A three-phase, 220-V, 60-Hz induction motor runsat 1,140 r/min. Determine the number of poles (forminimum slip), the slip, and the frequency of therotor currents.b. To reduce the starting current, a three-phasesquirrel cage induction motor is started byreducing the line voltage to Vs/2. By what factorare the starting torque and the starting currentreduced?
A three-phase induction motor, at rated voltageand frequency, has a starting torque of 140 percentand a maximum torque of 210 percent of full-loadtorque. Neglect stator resistance and rotational lossesand assume constant rotor resistance. Determinea. The slip at full load.b. The slip at maximum torque.c. The rotor current at starting as a percentage offull-load rotor current.
A three-phase 60 Hz induction motor connected to a three-phase bus at rated voltage isoperating at a low slip condition (i.e s < 20%) resulting in a steady state speed of 1090 rpm.(a) How many poles does the motor have?(b) What is the percentage slip at the operating speed?(c) What is the corresponding frequency, (fr) of the currents and voltages induced in therotor winding?
A 80 kW, 480-V, 60-Hz, six pole induction motor has a slip of 5 percent when operating at fullload conditions. At full-load conditions, the friction and windage losses are 300 W, and the core losses are 400 W. For full-load conditions, compute the induced torque,T-ind, in N-m.
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Design and develop equivalent circuit model of a single phase Induction motor with th consideration of core losses present with the parameter consideration of stator resistance R1 and reactance X1 and two rotor parameters which includes r2,x2 and magnetising reactance xm. (Illustration is required) Draw by hand please
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