Electrical Machines
Induction Machines
Marks 1Marks 2
Synchronous Machines
Marks 1Marks 2Marks 5
1
GATE EE 2017 Set 2
MCQ (Single Correct Answer)
+1
-0.3
If a synchronous motor is running at a leading power factor, its excitation induced voltage (Er) is
A
equal to terminal voltage Vt
B
higher than the terminal voltage Vt
C
less than terminal voltage Vt
D
dependent upon supply voltage Vt
2
GATE EE 2014 Set 3
MCQ (Single Correct Answer)
+1
-0.3
In a synchronous machine, hunting is predominantly damped by
A
mechanical losses in the rotor
B
iron losses in the rotor
C
copper losses in the stator
D
copper losses in the rotor
3
GATE EE 2014 Set 1
Numerical
+1
-0
A star connected 400 V, 50 Hz, 4 pole synchronous machine gave the following open circuit and short circuit test results:
Open circuit test: VOC = 400 V (rms, line–to–line) at field current, If = 2.3 A
Short circuit test: ISC = 10 A(rms, phase) at field current, If =1.5 A
The value of per phase synchronous impedance in Ω at rated voltage is __________.
Your input ____
4
GATE EE 2011
MCQ (Single Correct Answer)
+1
-0.3
A three-phase, salient pole synchronous motor is connected to an infinite bus. It is operated at no load a normal excitation. The field excitation of the motor is first reduced to zero and then increased in reverse direction gradually. Then the armature current
A
Increases continuously
B
First increases and then decreases steeply
C
First decreases and then increases steeply
D
Remains constant
GATE EE Subjects
Electromagnetic Fields
Signals and Systems
Engineering Mathematics
General Aptitude
Power Electronics
Power System Analysis
Analog Electronics
Control Systems
Digital Electronics
Electrical Machines
Electric Circuits
Electrical and Electronics Measurement