Electrical Machines
Induction Machines
Marks 1Marks 2
Synchronous Machines
Marks 1Marks 2Marks 5
1
GATE EE 2023
MCQ (Single Correct Answer)
+1
-0.33

The following columns present various modes of induction machine operation and the ranges of slip

A B
Mode of operation Range of Slip
a. Running in generator mode p) From 0.0 to 1.0
b. Running in motor mode q) From 1.0 to 2.0
c. Plugging in motor mode r) From $$-$$1.0 to 0.0

The correct matching between the elements in column A with those of column B is

A
a-r, b-p, and c-q
B
a-r, b-q, and c-p
C
a-p, b-r, and c-q
D
a-q, b-p, and c-r
2
GATE EE 2023
MCQ (Single Correct Answer)
+1
-0.33

The four stator conductors (A, A', B and B') of a rotating machine are carrying DC currents of the same value, the directions of which are shown in the figure (i). The rotor coils $$a$$-$$a'$$ and $$b$$-$$b'$$ are formed by connecting the back ends of conductors '$$a$$' and '$$a'$$' and '$$b$$' and '$$b'$$', respectively, as shown in figure (ii). The e.m.f. induced in coil $$a$$-$$a'$$ and coil $$b$$-$$b'$$ are denoted by $${E_{a - a'}}$$ and $${E_{b - b'}}$$, respectively. If the rotor is rotated at uniform angular speed $$\omega$$ rad/s in the clockwise direction then which of the following correctly describes the $${E_{a - a'}}$$ and $${E_{b - b'}}$$?

GATE EE 2023 Electrical Machines - D.C Machines Question 3 English

A
$${E_{a - a'}}$$ and $${E_{b - b'}}$$ have finite magnitudes and are in the same phase
B
$${E_{a - a'}}$$ and $${E_{b - b'}}$$ have finite magnitudes with $${E_{b - b'}}$$ leading $${E_{a - a'}}$$
C
$${E_{a - a'}}$$ and $${E_{b - b'}}$$ have finite magnitudes with $${E_{a - a'}}$$ leading $${E_{b - b'}}$$
D
$${E_{a - a'}}$$ = $${E_{b - b'}}$$ = 0
3
GATE EE 2023
Numerical
+1
-0

A separately excited DC motor rated 400 V, 15 A, 1500 RPM drives a constant torque load at rated speed operating from 400 V DC supply drawing rated current. The armature resistance is 1.2 $$\Omega$$. If the supply voltage drops by 10% with field current unaltered then the resultant speed of the motor in RPM is ____________ (Round off to the nearest integer).

Your input ____
4
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).
Your input ____
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