A 1200-V, 4-pole, de motor with 24 current paths, 200 coils and 50 turns per coil is rotating at 1000 rpm.Assume the total flux per pole is 0.02 Wb. and rotor circuit resistance is 1.8 Ohm.a) Find the voltage induced at its terminals.b) Find the current of the motor when it is connected to its rated voltage. Assume the brush voltagedrop is 28 V.c) Find the induced torque in the motor.d) Find the input electrical power supplied by the source.e) Find the electrical power delivered to the motor.f) If the core losses and mechanical losses are 3.2 kW, find the power delivered to the load.g) Find the motor efficiency (ignore the field losses). The de machine of Problem 1 is now rotating at 1200 rpm.a) Is it operating as a motor or generator? Find the induced voltage.b) Find the armature current assuming the same brush voltage drop.c) Find the induced torque.d) Find the machine efficiency assuming the same mechanical losses as Problem 1.

Q1DC Machine as a MotorPart 2: speed changes to 1200 rpm

Answered: A 1200-V, 4-pole, de motor with 24…

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 13RQ: A squirrel-cage induction motor is operating at 1175 RPM and producing a torque of 22 Ib-ft. What is...

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