A 1100 kVA, 4600V, 60HZ, three-phase, four-pole synchronous motor is (c) to be driven from a variable-frequency, three-phase, constant V/Hz inverter rated at 1250KVA. The synchronous motor has a synchronous reactance of 1.18 per unit and achieves rated open-circuit voltage at a field current of 85 A. i) With the motor operating at rated voltage and speed and an input power of 1000-kW, calculate the field current required to achieve unity-power- factor operation. ii) The input power in partc (i) varies as the speed to the power of 2.5 (input power x speed2). With the motor field-current held fixed, the inverter frequency is reduced such that the motor is operating at a speed of 1300 rpm. The inverter provides a constant V/F supply to the motor. Calculate the inverter frequency and the motor input power and power factor.

A 1100 kVA, 4600V, 60HZ, three-phase, four-pole synchronous motor is (c) to be driven from a variable-frequency, three-phase, constant V/Hz inverter rated at 1250KVA. The synchronous motor has a synchronous reactance of 1.18 per unit and achieves rated open-circuit voltage at a field current of 85 A. i) With the motor operating at rated voltage and speed and an input power of 1000-kW, calculate the field current required to achieve unity-power- factor operation. ii) The input power in partc (i) varies as the speed to the power of 2.5 (input power x speed2). With the motor field-current held fixed, the inverter frequency is reduced such that the motor is operating at a speed of 1300 rpm. The inverter provides a constant V/F supply to the motor. Calculate the inverter frequency and the motor input power and power factor.

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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