1
GATE EE 2002
Subjective
+5
-0
A $$230V,$$ $$250$$ $$rpm.$$ $$100A$$ separately excited $$dc$$ motor has an armature resistance of $$0.5\,\Omega .$$ The motor is connected to $$230V$$ $$dc$$ supply and rated $$dc$$ voltage is applied to the field winding. It is driving a load whose torque speed characteristic is given by $${T_L} = 500$$$$ - 10\omega ,$$ where $$\omega $$ is the rotational speed expressed in $$rad/sec$$ and $${T_L}$$ is the load torque in $$Nm.$$ Find the steady state speed at which the motor will drive the load and the armature current drawn by it from the source. Neglect the rotational losses of the machine.
2
GATE EE 2002
MCQ (Single Correct Answer)
+2
-0.6
A 400V/200V/200V, 50 Hz three winding transformer is connected as shown in Figure. The reading of the voltmeter 'V' will be GATE EE 2002 Electrical Machines - Transformers Question 55 English
A
0 V
B
400 V
C
600 V
D
800 V
3
GATE EE 2002
MCQ (Single Correct Answer)
+1
-0.3
A 1 kVA, 230V/100V, single phase, 50 Hz transformer having negligible winding resistance and leakage inductance is operating under saturation, while 250 V, 50 Hz sinusoidal supply is connected to the high voltage winding. A resistive load is connected to the low voltage winding which draws rated current. Which one of the following quantities will not be sinusoidal?
A
Voltage induced across the low voltage winding
B
Core flux
C
Load current
D
Current drawn from the source
4
GATE EE 2002
MCQ (Single Correct Answer)
+2
-0.6
A 200 V, 2000 rpm, 10A, separately excited d.c. motor has an armature resistance of 2 $$\Omega$$. Rated d.c. voltage is applied to both the armature and field winding of the motor. If the armature drawn 5A from the source, the torque developed by the motor is
A
4.30 Nm
B
4.77 Nm
C
0.45 Nm
D
0.50 Nm