A certain de shunt motor has R.= 0.5 ohm, Rr= 80 ohms. and kr= 0.02 s/rad (kr Ir= ka D). Under steady state operation from 120 V dc supply, I. = (a) Determine the speed and torque. = 20 A. (b) The field resistance is increased so that Ir= 1.0 A, with the shaft torque and the terminal voltage remaining constant. Evaluate the armature current and electromagnetic torque (i) (ii) Immediately after the field current changes. In the new steady state orks

A certain de shunt motor has R.= 0.5 ohm, Rr= 80 ohms. and kr= 0.02 s/rad (kr Ir= ka D). Under steady state operation from 120 V dc supply, I. = (a) Determine the speed and torque. = 20 A. (b) The field resistance is increased so that Ir= 1.0 A, with the shaft torque and the terminal voltage remaining constant. Evaluate the armature current and electromagnetic torque (i) (ii) Immediately after the field current changes. In the new steady state orks

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 6RQ: Name three factors that determine the torque produced by an induction motor.

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