1
GATE EE 2022
Numerical
+1
-0.33

A 280 V, separately excited DC motor with armature resistance of 1 $$\Omega$$ and constant field excitation drives a load. The load torque is proportional to the speed. The motor draws a current of 30 A when running at a speed of 1000 rpm. Neglect frictional losses in the motor. The speed, in rpm, at which the motor will run, if an additional resistance of value 10 $$\Omega$$ is connected in series with the armature, is __________. (round off to nearest integer).

2
GATE EE 2018
Numerical
+1
-0
A separately excited dc motor has an armature resistance R$$a$$ = 0.05⁡Ω. The field excitation is kept constant. At an armature voltage of 100 V, the motor produces a torque of 500 Nm at zero speed. Neglecting all mechanical losses, the no-load speed of the motor (in radian/s) for an armature voltage of 150 V is _____ (up to 2 decimal places).
3
GATE EE 2016 Set 1
+1
-0.3
A 4-pole, lap-connected, separately excited dc motor is drawing a steady current of 40 A while running at 600 rpm. A good approximation for the waveshape of the current in armature conductor of the motor is given by
A
B
C
D
4
GATE EE 2015 Set 2
+1
-0.3
A 4-pole, separately excited, wave wound DC machine with negligible armature resistance is rated for 230 V and 5 kW at a speed of 1200 rpm. If the same armature coils are reconnected to form a lap winding, what is the rated voltage (in volts) and power (in kW) respectively at 1200 rpm of the reconnected machine if the field circuit is left unchanged?
A
230 and 5
B
115 and 5
C
115 and 2.5
D
230 and 2.5
EXAM MAP
Medical
NEET