QA.3a)b)c)A 380 V, 50 Hz, 6-pole, 960 rpm, star connected inductionmotor has the following parameters: stator and rotorresistances are 1.25 each, and stator and rotor leakagereactance are 1.5 each (magnetising reactance can beneglected). The motor is controlled by simultaneous statorvoltage and frequency variation. Voltage boost is not usedand the motor is controlled using V/f = constant law. Themotor is supplied from a three-phase voltage source inverter.The motor operates at 30 Hz. Calculate the ratio of themaximum torque at this frequency with respect to the one atrated frequency, for both motoring and generation.For the same 30 Hz operating frequency, calculate ratio ofthe starting current at this frequency with respect to thestarting current at rated frequency.Assume that the voltage boost of 20 V (phase voltage) isused. Calculate new value of the phase voltage that wouldbe applied in this case for the operating frequency of 30 Hz.Repeat part b) with this new voltage applied. Induction motor torque dependence on the slip can be given for rated frequency, rated voltageoperation as:RrSTe(s) = =3PV₂2²2πfn2(R₁ + Rr)² + (X₁s + Xır) ²Maximum torque under the same conditions can be expressed as:3P1Tem Te(s = ±Sm)-· V₂2².4πfnRs ± √√R² + X²V

Answered: Image /qna-images/answer/3f33033b-7db7-4d29-812f-2a766192895a.jpg

QA.3 A 380 V, 50 Hz, 6-pole, 960 rpm, star connected induction motor has the following parameters: stator and rotor resistances are 1.25 each, and stator and rotor leakage reactance are 1.5 each (magnetising reactance can be neglected). The motor is controlled by simultaneous stator voltage and frequency variation. Voltage boost is not used and the motor is controlled using V/f = constant law. The motor is supplied from a three-phase voltage source inverter. The motor operates at 30 Hz. Calculate the ratio of the maximum torque at this frequency with respect to the one at rated frequency, for both motoring and generation.

QA.3 A 380 V, 50 Hz, 6-pole, 960 rpm, star connected induction motor has the following parameters: stator and rotor resistances are 1.25 each, and stator and rotor leakage reactance are 1.5 each (magnetising reactance can be neglected). The motor is controlled by simultaneous stator voltage and frequency variation. Voltage boost is not used and the motor is controlled using V/f = constant law. The motor is supplied from a three-phase voltage source inverter. The motor operates at 30 Hz. Calculate the ratio of the maximum torque at this frequency with respect to the one at rated frequency, for both motoring and generation.

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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