GATE EE 2024: Electrical Engineering
Text of page 1
Electrical Engineering (EE)
General Aptitude (GA)
Q.1 – Q.5 Carry ONE mark Each
Q.1 If ‘→’ denotes increasing order of intensity, then the meaning of the words
[talk → shout → scream] is analogous to [please → ________ → pander].
Which one of the given options is appropriate to fill the blank?
(A) flatter
(B) flutter
(C) fritter
(D) frizzle
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Electrical Engineering (EE)
Q.2 P and Q have been allotted a hostel room with two beds, a study table, and an
almirah. P is an avid bird-watcher and wants to sit at the table and watch birds
outside the window. Q does not mind that as long as his bed is close to the ceiling
fan.
Which one of the following arrangements suits them the most?
(A)
(B)
(C)
(D)
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Electrical Engineering (EE)
Q.3 The decimal number system uses the characters 0, 1, 2, …, 8, 9, and the octal
number system uses the characters 0, 1, 2, …, 6, 7.
For example, the decimal number 12 ( = 1 × 101 + 2 × 100 ) is expressed as
14 ( = 1 × 81 + 4 × 80 ) in the octal number system.
The decimal number 108 in the octal number system is
(A) 168
(B) 108
(C) 150
(D) 154
Q.4 A shopkeeper buys shirts from a producer and sells them at 20% profit. A customer
has to pay ₹3,186.00 including 18% taxes, per shirt. At what price did the
shopkeeper buy each shirt from the producer?
(A) ₹2,500.00
(B) ₹1,975.40
(C) ₹2,250.00
(D) ₹2,548.80
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Electrical Engineering (EE)
Q.5 If, for non-zero real variables x, y, and real parameter a > 1,
x: y = (a + 1) ∶ (a − 1),
then, the ratio (x 2 − y 2 ) ∶ (x 2 + y 2 ) is
(A) 2a ∶ (a2 + 1)
(B) a ∶ (a2 + 1)
(C) 2a ∶ (a2 − 1)
(D) a ∶ (a2 − 1)
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Q.6 – Q.10 Carry TWO marks Each
Q.6 In the given text, the blanks are numbered (i)−(iv). Select the best match for
all the blanks.
(i) (ii)
Following a row the shopkeeper the price of a frying pan, the
(iii) (iv)
cook stood a row to withdraw cash the ATM booth.
(A) (i) with (ii) over (iii) at (iv) with
(B) (i) at (ii) over (iii) over (iv) in
(C) (i) with (ii) over (iii) in (iv) at
(D) (i) over (ii) with (iii) over (iv) at
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Q.7 In the following figure,
CD = 5 cm, BE = 10 cm, AE = 12 cm,
∠DAB = ∠DCB, and ∠DAE = ∠DBC = 90°
Points AFCD create a rhombus.
The length of BF (in cm) is
(A) 3
(B) 2
(C) 4
(D) 6
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Q.8 The chart below shows the data of the number of cars bought by Millennials and
Gen X people in a country from the year 2010 to 2020 as well as the yearly fuel
consumption of the country (in Million liters).
Gen X Millenials Fuel Consumption
100 100000
Fuel Consumption (Million liters) Number of people buying cars
90 90000
80 80000
70 70000
60 60000
50 50000
40 40000
30 30000
20 20000
10 10000
0 0
2010 2015 2020
Year
Considering the data presented in the chart, which one of the following options is
true?
(A) The percentage increase in fuel consumption from 2010 to 2015 is more than the
percentage increase in fuel consumption from 2015 to 2020.
(B) The increase in the number of Millennial car buyers from 2015 to 2020 is less than
the decrease in the number of Gen X car buyers from 2010 to 2015.
(C) The increase in the number of Millennial car buyers from 2010 to 2015 is more than
the decrease in the number of Gen X car buyers from 2010 to 2015.
(D) The decrease in the number of Gen X car buyers from 2015 to 2020 is more than
the increase in the number of Millennial car buyers from 2010 to 2015.
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Q.9 The assembly shown below has three teethed circular objects (Pinions) and two
teethed flat objects (Racks), which are perfectly mating with each other. Pinions can
only rotate clockwise or anti-clockwise staying at its own center. Racks can
translate towards the left (←) or the right (→) direction.
If the object A (Rack) is translating towards the right (→) direction, the correct
statement among the following is
(A) Object B translates towards the right direction.
(B) Object B translates towards the left direction.
(C) Object R rotates in the anticlockwise direction.
(D) Object Q rotates in the clockwise direction.
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Q.10 A surveyor has to measure the horizontal distance from her position to a distant
reference point C. Using her position as the center, a 200 m horizontal line segment
is drawn with the two endpoints A and B. Points A, B, and C are not collinear. Each
of the angles ∠CAB and ∠CBA are measured as 87.8°. The distance (in m) of the
reference point C from her position is nearest to
(A) 2603
(B) 2606
(C) 2306
(D) 2063
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Q.11 – Q.35 Carry ONE mark Each
Q.11 Which one of the following matrices has an inverse?
(A) 1 4 8
[0 4 2]
0.5 2 4
(B) 1 2 3
[2 4 6]
3 2 9
(C) 1 4 8
[0 4 2]
1 2 4
(D) 1 4 8
[0 4 2]
3 12 24
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Q.12 The number of junctions in the circuit is
(A) 6
(B) 7
(C) 8
(D) 9
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Q.13 All the elements in the circuit are ideal. The power delivered by the 10 V source in
watts is
αΩ 2Ω
10 V 1Ω 10 A
(A) 0
(B) 50
(C) 100
(D) dependent on the value of α
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Q.14 The circuit shown in the figure with the switch S open, is in steady state. After the
switch S is closed, the time constant of the circuit in seconds is
S 1Ω 1H
1Ω 1H
1A
1H
1H
(A) 1.25
(B) 0
(C) 1
(D) 1.5
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Q.15 Suppose signal y(t) is obtained by the time-reversal of signal x(t), i.e.,
y(t) = x(−t), −∞ < t < ∞. Which one of the following options is always true
for the convolution of x(t) and y(t)?
(A) It is an even signal.
(B) It is an odd signal.
(C) It is a causal signal.
(D) It is an anti-causal signal.
Q.16 If u(t) is the unit step function, then the region of convergence (ROC) of the
Laplace transform of the signal
2
x(t) = e t [u(t − 1) − u(t − 10)]
is
(A) − Re( s)
(B) Re( s) 10
(C) Re( s) 1
(D) 1 Re( s) 10
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Q.17 A three phase, 50 Hz, 6 pole induction motor runs at 960 rpm. The stator copper
loss, core loss, and the rotational loss of the motor can be neglected. The percentage
efficiency of the motor is
(A) 92
(B) 94
(C) 96
(D) 98
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Q.18 Which one of the following options represents possible voltage polarities in a single
phase two winding transformer? Here, Vp is the applied primary voltage, Ep is the
induced primary voltage, Vs is the open circuit secondary voltage, and Es is the
induced secondary voltage.
(A)
+ + + +
Vp Ep Es Vs
− − − −
(B)
− − + +
Vp Ep Es Vs
+ + − −
(C)
+ − − +
Vp Ep Es Vs
− + + −
(D)
+ − − −
Vp Ep Es Vs
− + + +
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Q.19 The figure shows the single line diagram of a 4-bus power network. Branches b1 ,
b2 , b3 , and b4 have impedances 4z, z, 2z, and 4z per-unit (pu), respectively, where
z = r + jx, with r > 0 and x > 0. The current drawn from each load bus (marked
as arrows) is equal to I pu, where I ≠ 0. If the network is to operate with minimum
loss, the branch that should be opened is
b1 b2
I b3 b4 I
I
(A) b1
(B) b2
(C) b3
(D) b4
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Q.20 C(s)
For the block-diagram shown in the figure, the transfer function is
R(s)
_
R(s) + _ C(s)
G(s)
+
(A) G(s)
1 + 2G(s)
(B) G(s)
−
1 + 2G(s)
(C) G(s)
1 − 2G(s)
(D) G(s)
−
1 − 2G(s)
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2
ωn
Q.21
Consider the standard second-order system of the form 2 with the
s 2 +2ζωn s+ωn
poles p and p∗ having negative real parts. The pole locations are also shown in the
figure. Now consider two such second-order systems as defined below:
System 1: ωn = 3 rad/sec and θ = 60°
System 2: ωn = 1 rad/sec and θ = 70°
Which one of the following statements is correct?
jω
p×
θ
−ωn 0 σ
×
p∗
(A) Settling time of System 1 is more than that of System 2.
(B) Settling time of System 2 is more than that of System 1.
(C) Settling times of both the systems are the same.
(D) Settling time cannot be computed from the given information.
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Q.22 Consider the cascaded system as shown in the figure. Neglecting the faster
component of the transient response, which one of the following options is a first-
order pole-only approximation such that the steady-state values of the unit step
responses of the original and the approximated systems are same?
Input 1 s + 40 Output
s+1 s + 20
(A) 1
s+1
(B) 2
s+1
(C) 1
s + 20
(D) 2
s + 20
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Electrical Engineering (EE)
Q.23 The table lists two instrument transformers and their features:
Instrument Transformers Features
P) Primary is connected in parallel to the grid
X) Current Transformer (CT) Q) Open circuited secondary is not desirable
Y) Potential Transformer (PT) R) Primary current is the line current
S) Secondary burden affects the primary current
The correct matching of the two columns is
(A) X matches with P and Q; Y matches with R and S.
(B) X matches with P and R; Y matches with Q and S.
(C) X matches with Q and R; Y matches with P and S.
(D) X matches with Q and S; Y matches with P and R.
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Q.24 Simplified form of the Boolean function
F(P, Q, R, S) = P̅ Q̅ + P̅ QS + PQ̅ R̅ S̅ + PQ̅ RS̅
is
(A) P̅S + Q̅ S̅
(B) P̅Q̅ + Q̅ S̅
(C) P̅Q + RS̅
(D) PS̅ + QR̅
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Q.25 In the circuit, the present value of Z is 1. Neglecting the delay in the combinatorial
circuit, the values of S and Z, respectively, after the application of the clock will be
Z
Z D
Q
X=1 S = X⊕Y⊕Z
S
Clock Q̅
Y=0
Combinatorial D Flip-flop
Circuit
(A) S = 0, Z = 0
(B) S = 0, Z = 1
(C) S = 1, Z = 0
(D) S = 1, Z = 1
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Q.26 To obtain the Boolean function F(X, Y) = XY̅ + X̅, the inputs PQRS in the figure
should be
4:1 Multiplexer
P 0
Q 1
F(X, Y)
R 2
S 3 MSB LSB
S1 S0
S1 and S0 are the select lines.
X Y
(A) 1010
(B) 1110
(C) 0110
(D) 0001
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Q.27 If the following switching devices have similar power ratings, which one of them is
the fastest?
(A) SCR
(B) GTO
(C) IGBT
(D) Power MOSFET
Q.28 A single-phase triac based AC voltage controller feeds a series RL load. The input
AC supply is 230 V, 50 Hz. The values of R and L are 10 Ω and 18.37 mH,
respectively. The minimum triggering angle of the triac to obtain controllable output
voltage is
(A) 15°
(B) 30°
(C) 45°
(D) 60°
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Q.29 Let X be a discrete random variable that is uniformly distributed over the set
{−10, −9, ⋯ , 0, ⋯ , 9, 10}. Which of the following random variables is/are
uniformly distributed?
(A) X2
(B) X3
(C) (X − 5)2
(D) (X + 10)2
Q.30 Which of the following complex functions is/are analytic on the complex plane?
(A) f(z) = jRe(z)
(B) f(z) = Im(z)
(C) f(z) = e |z|
(D) f(z) = z 2 − z
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2
Q.31 Consider the complex function f(z) = cos z + e z . The coefficient of z 5 in the
Taylor series expansion of f(z) about the origin is ______ (rounded off to 1
decimal place).
Q.32 1 22
The sum of the eigenvalues of the matrix A= [ ] is ______ (rounded off to the
3 4
nearest integer).
Q.33 Let X ( ) be the Fourier transform of the signal
4
x(t) = e −t cos t, − ∞ < t < ∞.
The value of the derivative of X ( ) at = 0 is _______ (rounded off to 1 decimal
place).
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Q.34 The incremental cost curves of two generators (Gen A and Gen B) in a plant
supplying a common load are shown in the figure. If the incremental cost of
supplying the common load is Rs. 7400 per MWh, then the common load in MW is
_______ (rounded off to the nearest integer).
13000
12000
Incremental cost (Rs./MWh)
11000
10000
9000
8000
7000
6000
5000
0 20 40 60 80 100 120 140 160
Generation (MW)
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Q.35 A forced commutated thyristorized step-down chopper is shown in the figure.
Neglect the ON-state drop across the power devices. Assume that the capacitor is
initially charged to 50 V with the polarity shown in the figure. The load current (IL )
can be assumed to be constant at 10 A. Initially, ThM is ON and ThA is OFF. The
turn-off time available to ThM in microseconds, when ThA is triggered, is_________
(rounded off to the nearest integer).
ThM
IL = 10 A
+
10 μF
−
+ L
50 V Constant
−
Current
Load
ThA
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Q.36 – Q.65 Carry TWO marks Each
Q.36 Consider a vector u̅ = 2x̂ + ŷ + 2ẑ , where x̂, ŷ, ẑ represent unit vectors along the
coordinate axes x, y, z respectively. The directional derivative of the function
f(x, y, z) = 2 ln(xy) + ln(yz) + 3 ln(xz) at the point (x, y, z) = (1, 1, 1) in the
direction of u̅ is
(A) 0
(B) 7
5√2
(C) 7
(D) 21
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Q.37 The input x(t) and the output y(t) of a system are related as
t
y(t) = e −t ∫ e τ x(τ) dτ, − ∞ < t < ∞.
−∞
The system is
(A) nonlinear.
(B) linear and time-invariant.
(C) linear but not time-invariant.
(D) noncausal.
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Q.38 Consider the discrete-time systems T1 and T2 defined as follows:
{T1 x}[n] = x[0] + x[1] + ⋯ + x[n]
1 1
{T2 x}[n] = x[0] + x[1] + ⋯ + n x[n]
2 2
Which one of the following statements is true?
(A) T1 and T2 are BIBO stable.
(B) T1 and T2 are not BIBO stable.
(C) T1 is BIBO stable but T2 is not BIBO stable.
(D) T1 is not BIBO stable but T2 is BIBO stable.
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Q.39 If the Z-transform of a finite-duration discrete-time signal x[n] is X(z), then the Z-
transform of the signal y[n] = x[2n] is
(A) Y(z) = X(z 2 )
(B) 1
Y(z) = [X(z −1/2 ) + X(−z −1/2 )]
2
(C) 1
Y(z) = [X(z1/2 ) + X(−z1/2 )]
2
(D) 1
Y(z) = [X(z 2 ) + X(−z 2 )]
2
Q.40 A 3-phase, 11 kV, 10 MVA synchronous generator is connected to an inductive
load of power factor (√3/2) via a lossless line with a per-phase inductive reactance
of 5 Ω. The per-phase synchronous reactance of the generator is 30 Ω with
negligible armature resistance. If the generator is producing the rated current at the
rated voltage, then the power factor at the terminal of the generator is
(A) 0.63 lagging.
(B) 0.87 lagging.
(C) 0.63 leading.
(D) 0.87 leading.
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Q.41 For the three-bus lossless power network shown in the figure, the voltage
magnitudes at all the buses are equal to 1 per unit (pu), and the differences of the
voltage phase angles are very small. The line reactances are marked in the figure,
where α, β, γ, and x are strictly positive. The bus injections P1 and P2 are in pu. If
P1 = mP2 , where m > 0, and the real power flow from bus 1 to bus 2 is 0 pu, then
which one of the following options is correct?
bus 1 bus 2
P1 P2
jαx Ω
jβx Ω jγx Ω
bus 3
(A) γ = mβ
(B) β = mγ
(C) α = mγ
(D) α = mβ
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Q.42 A BJT biasing circuit is shown in the figure, where VBE = 0.7 V and β = 100. The
Quiescent Point values of VCE and IC are respectively
VCC = +12 V
R1 = 100 kΩ RC = 2 kΩ
IC
+
VCE
_
R2 = 50 kΩ RE = 1 kΩ
(A) 4.6 V and 2.46 mA
(B) 3.5 V and 2.46 mA
(C) 2.61 V and 3.13 mA
(D) 4.6 V and 3.13 mA
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Q.43 Let f(t) be a real-valued function whose second derivative is positive for
−∞ < t < ∞. Which of the following statements is/are always true?
(A) f(t) has at least one local minimum.
(B) f(t) cannot have two distinct local minima.
(C) f(t) has at least one local maximum.
(D) The minimum value of f(t) cannot be negative.
Q.44 Consider the function f(t) = (max(0, t))2 for −∞ < t < ∞, where max(a, b)
denotes the maximum of a and b. Which of the following statements is/are true?
(A) f(t) is not differentiable.
(B) f(t) is differentiable and its derivative is continuous.
(C) f(t) is differentiable but its derivative is not continuous.
(D) f(t) and its derivative are differentiable.
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Q.45 Which of the following differential equations is/are nonlinear?
(A) dx(t)
t x(t) + = t 2e t , x(0) = 0
dt
(B) 1 t dx(t)
e + x(t) = 0, x(0) = 0
2 dt
(C) dx(t)
x(t) cos t − sin t = 1, x(0) = 0
dt
(D) dx(t)
( )
x(t) + e dt = 1, x(0) = 0
Q.46 For a two-phase network, the phase voltages Vp and Vq are to be expressed in terms
Vp Vα
of sequence voltages Vα and Vβ as [ ] = S [V ]. The possible option(s) for matrix
Vq β
S is/are
(A) 1 1
[ ]
1 −1
(B) 1 1
[ ]
1 1
(C) 1 1
[ ]
1 0
(D) −1 1
[ ]
1 1
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Q.47 Which of the following options is/are correct for the Automatic Generation Control
(AGC) and Automatic Voltage Regulator (AVR) installed with synchronous
generators?
(A) AGC response has a local effect on frequency while AVR response has a global
effect on voltage.
(B) AGC response has a global effect on frequency while AVR response has a local
effect on voltage.
(C) AGC regulates the field current of the synchronous generator while AVR regulates
the generator’s mechanical power input.
(D) AGC regulates the generator’s mechanical power input while AVR regulates the
field current of the synchronous generator.
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Q.48 Two passive two-port networks P and Q are connected as shown in the figure. The
40 Ω 60 Ω
impedance matrix of network P is ZP = [ ]. The admittance matrix of
80 Ω 100 Ω
5S −2.5 S
network Q is YQ = [ ]. Let the ABCD matrix of the two-port
−2.5 S 1S
α β
network R in the figure be [ ]. The value of β in Ω is _____________ (rounded
γ δ
off to 2 decimal places).
Two-port Two-port
network network
P Q
Two-port network R
Q.49 For the circuit shown in the figure, the source frequency is 5000 rad/sec. The
mutual inductance between the magnetically coupled inductors is 5 mH with their
self inductances being 125 mH and 1 mH. The Thevenin’s impedance, Ztℎ ,
between the terminals P and Q in Ω is _________ (rounded off to 2 decimal places).
4Ω 2Ω
Zs
P
50 μF
Source Ztℎ 4Ω 125 mH
1 mH
Q
5 mH
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Q.50 In the circuit shown, Z1 = 50∠ − 90° Ω and Z2 = 200∠ − 30° Ω. It is supplied by
a three phase 400 V source with the phase sequence being R-Y-B. Assume the watt
meters W1 and W2 to be ideal. The magnitude of the difference between the readings
of W1 and W2 in watts is ___________ (rounded off to 2 decimal places).
cc _ W1
R +
pc _
+
Z1 Z2
pc +
B _
W2 cc _
Y +
Q.51 In the (x, y, z) coordinate system, three point-charges Q, Q, and αQ are located in
free space at (−1, 0, 0), (1, 0, 0), and (0, −1, 0), respectively. The value of α for the
electric field to be zero at (0, 0.5, 0) is ______________ (rounded off to 1 decimal
place).
Q.52 The given equation represents a magnetic field strength H ̅ (r, θ, φ) in the spherical
coordinate system, in free space. Here, r̂ and θ̂ represent the unit vectors along r
and θ, respectively. The value of P in the equation should be ____________
(rounded off to the nearest integer).
1
̅ (r, θ, φ) =
H (r̂ P cos θ + θ̂ sin θ)
r3
Q.53 If the energy of a continuous-time signal x(t) is E and the energy of the signal
2x(2t − 1) is cE, then c is _____ (rounded off to 1 decimal place).
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Q.54 A 3-phase star connected slip ring induction motor has the following parameters
referred to the stator:
Rs = 3 Ω, Xs = 2 Ω, Xr′ = 2 Ω, Rr′ = 2.5 Ω
The per phase stator to rotor effective turns ratio is 3:1. The rotor winding is also
star connected. The magnetizing reactance and core loss of the motor can be
neglected. To have maximum torque at starting, the value of the extra resistance in
ohms (referred to the rotor side) to be connected in series with each phase of the
rotor winding is _________ (rounded off to 2 decimal places).
Q.55 A 5 kW, 220 V DC shunt motor has 0.5 Ω armature resistance including brushes.
The motor draws a no-load current of 3 A. The field current is constant at 1 A.
Assuming that the core and rotational losses are constant and independent of the
load, the current (in amperes) drawn by the motor while delivering the rated load,
for the best possible efficiency, is ________ (rounded off to 2 decimal places).
Q.56 The single line diagram of a lossless system is shown in the figure. The system is
operating in steady-state at a stable equilibrium point with the power output of the
generator being Pmax sin δ, where δ is the load angle and the mechanical power
input is 0.5Pmax . A fault occurs on line 2 such that the power output of the generator
is less than 0.5Pmax during the fault. After the fault is cleared by opening line 2, the
power output of the generator is {Pmax /√2} sin δ. If the critical fault clearing angle
is π/2 radians, the accelerating area on the power angle curve is ______ times Pmax
(rounded off to 2 decimal places).
Line 1
Line 2
Generator Infinite
bus bus
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Electrical Engineering (EE)
Q.57 Consider the closed-loop system shown in the figure with
K(s 2 − 2s + 2)
G(s) = .
(s 2 + 2s + 5)
The root locus for the closed-loop system is to be drawn for 0 ≤ K < ∞. The angle
of departure (between 0° and 360°) of the root locus branch drawn from the pole
(−1 + j2), in degrees, is _________________ (rounded off to the nearest integer).
R(s) + C(s)
G(s)
_
Q.58 Consider the stable closed-loop system shown in the figure. The asymptotic Bode
magnitude plot of G(s) has a constant slope of −20 dB/decade at least till
100 rad/sec with the gain crossover frequency being 10 rad/sec. The asymptotic
Bode phase plot remains constant at −90° at least till ω = 10 rad/sec. The steady-
state error of the closed-loop system for a unit ramp input is ______________
(rounded off to 2 decimal places).
R(s) + C(s)
G(s)
_
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Electrical Engineering (EE)
Q.59 Consider the stable closed-loop system shown in the figure. The magnitude and
phase values of the frequency response of G(s) are given in the table. The value of
the gain KI (> 0) for a 50° phase margin is _______ (rounded off to 2 decimal
places).
ω in rad/sec Magnitude in dB Phase in degrees
0.5 −7 −40
1.0 −10 −80
2.0 −18 −130
10.0 −40 −200
R(s) + KI C(s)
G(s)
s
_
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Electrical Engineering (EE)
Q.60 In the given circuit, the diodes are ideal. The current I through the diode D1 in
milliamperes is ___________ (rounded off to two decimal places).
+10 V +3 V
1 kΩ D1 I
D2
1 kΩ
1 kΩ 1 kΩ
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Electrical Engineering (EE)
Q.61 A difference amplifier is shown in the figure. Assume the op-amp to be ideal. The
CMRR (in dB) of the difference amplifier is _________ (rounded off to 2 decimal
places).
10.5 kΩ 101 kΩ
+
vin1
_ _
9.5 kΩ +
+ vo
_
+
vin2 101.5 kΩ
_
Q.62 A single-phase half-controlled bridge converter supplies an inductive load with
ripple free load current. The triggering angle of the converter is 60°. The ratio of
the rms value of the fundamental component of the input current to the rms value
of the total input current of the bridge is _________ (rounded off to 3 decimal
places).
Q.63 A single-phase full bridge voltage source inverter (VSI) feeds a purely inductive
load. The inverter output voltage is a square wave in 180° conduction mode. The
fundamental frequency of the output voltage is 50 Hz. If the DC input voltage of
the inverter is 100 V and the value of the load inductance is 20 mH, the peak-to-
peak load current in amperes is _________ (rounded off to the nearest integer).
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Electrical Engineering (EE)
Q.64 In the DC-DC converter shown in the figure, the current through the inductor is
continuous. The switching frequency is 500 Hz. The voltage (Vo ) across the load is
assumed to be constant and ripple free. The peak inductor current in amperes is
_________ (rounded off to the nearest integer).
L = 2 mH
Ii Io
+ +
Vi = 20 V _ S Vo = 40 V _ 10 Ω
Q.65 A single-phase full-controlled thyristor converter bridge is used for regenerative
braking of a separately excited DC motor with the following specifications:
Rated armature voltage 210 V
Rated armature current 10 A
Rated speed 1200 rpm
Armature resistance 1Ω
Input to the converter bridge 240 V at 50 Hz
The armature of the DC motor is fed from the
full-controlled bridge and the field current is kept
constant.
Assume that the motor is running at 600 rpm and the armature terminals of the
motor are suitably reversed for regenerative braking. If the armature current of the
motor is to be maintained at the rated value, the triggering angle of the converter
bridge in degrees should be ____________ (rounded off to 2 decimal places).
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Electrical Engineering (EE)
Final Answer Key
Question
Q. No. Session Section Key/Range Mark
Type
1 8 MCQ GA A 1
2 8 MCQ GA A 1
3 8 MCQ GA D 1
4 8 MCQ GA C 1
5 8 MCQ GA A 1
6 8 MCQ GA C 2
7 8 MCQ GA MTA 2
8 8 MCQ GA C 2
9 8 MCQ GA B 2
10 8 MCQ GA A 2
11 8 MCQ EE C 1
12 8 MCQ EE A 1
13 8 MCQ EE A 1
14 8 MCQ EE A 1
15 8 MCQ EE A 1
16 8 MCQ EE A 1
17 8 MCQ EE C 1
18 8 MCQ EE MTA 1
19 8 MCQ EE C 1
20 8 MCQ EE D 1
21 8 MCQ EE B 1
22 8 MCQ EE B 1
23 8 MCQ EE C 1
24 8 MCQ EE A 1
25 8 MCQ EE C 1
26 8 MCQ EE B 1
27 8 MCQ EE D 1
28 8 MCQ EE B 1
29 8 MSQ EE B; D 1
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Text of page 2
30 8 MSQ EE D 1
31 8 NAT EE 0.0 to 0.0 1
32 8 NAT EE 29 to 29 1
33 8 NAT EE 0.0 to 0.0 1
34 8 NAT EE 35 to 35 1
35 8 NAT EE 50 to 50 1
36 8 MCQ EE C 2
37 8 MCQ EE B 2
38 8 MCQ EE D 2
39 8 MCQ EE C 2
40 8 MCQ EE A 2
41 8 MCQ EE A 2
42 8 MCQ EE A 2
43 8 MSQ EE B 2
44 8 MSQ EE B 2
45 8 MSQ EE B; D 2
46 8 MSQ EE A; D 2
47 8 MSQ EE B; D 2
48 8 NAT EE -19.90 to -19.70 2
49 8 NAT EE 5.32 to 5.34 2
50 8 NAT EE 692 to 693 2
51 8 NAT EE -1.7 to -1.5 2
52 8 NAT EE 2 to 2 2
53 8 NAT EE 2.0 to 2.0 2
54 8 NAT EE 0.26 to 0.29 2
55 8 NAT EE 27.19 to 27.39 2
56 8 NAT EE 0.10 to 0.12 2
57 8 NAT EE 4 to 8 2
58 8 NAT EE 0.09 to 0.11 2
59 8 NAT EE 1.11 to 1.13 2
60 8 NAT EE 1.64 to 1.70 2
61 8 NAT EE 39.50 to 41.50 2
62 8 NAT EE 0.940 to 0.970 2
63 8 NAT EE 50 to 50 2
64 8 NAT EE 13 to 13 2
65 8 NAT EE 113.00 to 116.00 2
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Source: GATE. Question paper published by GATE.