6. To keep the flux-density peak in the air gap at the rated value, why do the voltage magnitudes, at a given frequency of operation, depend on the torque being supplied by the motor? 7. At start-up, why should small-frequency voltages be applied initially? What determines the rate at which the frequency can be ramped up? 8. At speeds below the rated value, what is the limit on the torque that can be delivered, and why? 9. At speeds above the rated value, what is the limit on the power that can be delivered, and why? What does it mean for the torque that can be delivered above the rated speed?

6. To keep the flux-density peak in the air gap at the rated value, why do the voltage magnitudes, at a given frequency of operation, depend on the torque being supplied by the motor? 7. At start-up, why should small-frequency voltages be applied initially? What determines the rate at which the frequency can be ramped up? 8. At speeds below the rated value, what is the limit on the torque that can be delivered, and why? 9. At speeds above the rated value, what is the limit on the power that can be delivered, and why? What does it mean for the torque that can be delivered above the rated speed?

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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Reducing the supply voltage so that Vnew = Vold / V3 reduces the maximum torque of the motor so that Tmaxnew= ...Tmaxold . * .... ...
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