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Previous GATE
0
votes
0
answers
1
GATE2015123
The primary mmf is least affected by the secondary terminal conditions in a Power transformer. Potential transformer. Current transformer. Distribution transformer.
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
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gate2015ee1
primarymmf
turnratio
0
votes
0
answers
2
GATE2014114
The undesirable property of an electrical insulating material is high dielectric strength High relative permittivity high thermal conductivity High insulation resistivity
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
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gate2014ee1
insulation
powersystemanalysis
conductingwires
0
votes
0
answers
3
GATE2014315
For a fully transposed transmission line positive, negative and zero sequence impedances are equal positive and negative sequence impedances are equal zero and positive sequence impedances are equal negative and zero sequence impedances are equal
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee3
transmissionline
sequences
0
votes
0
answers
4
GATE2014216
Shunt reactors are sometimes used in high voltage transmission systems to limit the short circuit current through the line. compensate for the series reactance of the line under heavily loaded condition. limit overvoltages at the load side under lightly loaded condition. compensate for the voltage drop in the line under heavily loaded condition.
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee2
transmission
system
seriesreactors
0
votes
0
answers
5
GATE20138
A singlephase load is supplied by a singlephase voltage source. If the current flowing from the load to the source is $10\angle 150^0\: A$ and if the voltage at the load terminals is $100\angle 60^0\: V$, then the Load ... Load absorbs real power and absorbs reactive power. Load delivers real power and delivers reactive power. Load delivers real power and absorbs reactive power.
asked
Feb 12, 2017
in
Power Systems
by
piyag476
(
1.5k
points)
gate2013ee
reactivepower
realpower
0
votes
0
answers
6
GATE2016121
Consider a system consisting of a synchronous generator working at a lagging power factor, a synchronous motor working at an overexcited condition and a directly gridconnected induction generator. Consider capacitive $VAr$ ... is a source and induction generator and synchronous generator are sinks of reactive power. All are sources of reactive power.
asked
Jan 30, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2016ee1
unitypowerfactor
sourceofreactivepower
load
0
votes
0
answers
7
GATE2014353
A threephase fully controlled bridge converter is fed through stardelta transformer as shown in the figure. The converter is operated at a firing angle of $300$. Assuming the load current ($I_0)$ to be virtually constant at $1$ $p.u$. and transformer to be an ideal one, the input phase current waveform is
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee3
starconnection
deltaconnection
0
votes
0
answers
8
GATE2015141
Consider the economic dispatch problem for a power plant having two generating units. The fuel costs in Rs/MWh along with the generation limits for the two units are given below: $C_{1}(P_{1})=0.01P^{2}_{1}+30P_{1}+10 ; 100MW \leq P_{1}\leq 150MW$ ... $200$ MW is _______.
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2015ee1
economicdispatch
incrementalcost
numericalanswers
0
votes
0
answers
9
GATE201526
A $3$phase balanced load which has a power factor of $0.707$ is connected to a balanced supply. The power consumed by the load is $5$ kW. The power is measured by the twowattmeter method. The readings of the two wattmeters are $3.94$ kW and $1.06$ kW $2.50$ kW and $2.50$ kW $5.00$ kW and $0.00$ kW $2.96$ kW and $2.04$ kW
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2015ee2
balancedoperation
powermeasurement
0
votes
0
answers
10
GATE2014316
A $183$bus power system has $150$ $PQ$ buses and $32$ $PV$ buses. In the general case, to obtain the load flow solution using NewtonRaphson method in polar coordinates, the minimum number of simultaneous equations to be solved is ___________.
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee3
slackbus
linelosses
numericalanswers
0
votes
0
answers
11
GATE2014119
Power consumed by a balanced $3$phase, $3$wire load is measured by the two wattmeter method. The first wattmeter reads twice that of the second. Then the load impedance angle in radians is $\pi /12$ $\pi /8$ $\pi /6$ $\pi /3$
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
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gate2014ee1
balancedsystem
load
impedance
0
votes
0
answers
12
GATE2015117
Base load power plants are P: wind farms. Q: runofriver plants. R: nuclear power plants. S: diesel power plants. P, Q and S only P, R and S only P, Q and R only Q and R only
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2015ee1
powerplants
powergeneration
0
votes
0
answers
13
GATE2014115
Threephase to ground fault takes place at locations $F_1$ and $F_2$ in the system shown in the figure If the fault takes place at location $F_1$, then the voltage and the current at bus $A$ are $V_{F1}$ and $I_{F1}$ respectively. If the fault takes place at location $F_2$, then the ... $I_{F1}$ and $V_{F2}$ leads $I_{F2}$ $V_{F1}$ lags $I_{F1}$ and $V_{F2}$ lags $I_{F2}$
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee1
singlelinediagram
powerfactor
0
votes
0
answers
14
GATE2015216
The synchronous generator shown in the figure is supplying active power to an infinite bus via two short, lossless transmission lines, and is initially in steady state. The mechanical power input to the generator and the voltage magnitude $E$ are constant. If one ... transient. Which one of the following waveforms of the rotor angle $\delta$ shows the transient correctly?
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2015ee2
powersystemprotection
sourceofreactivepower
0
votes
0
answers
15
GATE2015144
A sustained threephase fault occurs in the power system shown in the figure. The current and voltage phasors during the fault (on a common reference), after the natural transients have died down, are also shown. Where is the fault located? Location $P$ Location $Q$ Location $R$ Location $S$
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2015ee1
singlelinediagram
faultanalysis
0
votes
0
answers
16
GATE2016253
Two identical unloaded generators are connected in parallel as shown in the figure. Both the generators are having positive, negative and zero sequence impedances of $j0.4$ p.u., $j0.3$ p.u. and $j0.15$ p.u., respectively. If the prefault voltage is $1$ p.u., for a linetoground $(LG)$ fault at the terminals of the generators, the fault current, in p.u., is ___________.
asked
Jan 30, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2016ee2
sequenceimpedences
prefaultvoltage
numericalanswers
0
votes
0
answers
17
GATE2014314
In a long transmission line with $r$,$l$,$g$ and $c$ are the resistance, inductance, shunt conductance and capacitance per unit length, respectively, the condition for distortionless transmission is $rc=lg$ $r=\sqrt{l/c}$ $rg=lc$ $g=\sqrt{c/l}$
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee3
longtransmissionline
distortion
0
votes
0
answers
18
GATE2016236
In the balanced $3$phase, $50$ Hz, circuit shown below, the value of inductance $(L)$ is $10$ mH. The value of the capacitance $(C)$ for which all the line currents are zero, in millifarads, is ___________.
asked
Jan 30, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2016ee2
balancedsystem
line
currents
numericalanswers
0
votes
0
answers
19
GATE201426
Two identical coupled inductors are connected in series. The measured inductances for the two possible series connections are $380$ $μH$ and $240$ $μH$. Their mutual inductance in $μH$ is ________
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee2
passiveloads
seriesconnection
numericalanswers
0
votes
0
answers
20
GATE2014116
A $2$bus system and corresponding zero sequence network are shown in the figure. The transformers $T_1$and $T_2$ are connected as
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee1
sequencenetworks
bussystem
0
votes
0
answers
21
GATE2014240
A synchronous generator is connected to an infinite bus with excitation voltage $E_f$ = $1.3$ $pu$. The generator has a synchronous reactance of $1.1$ $pu$ and is delivering real power $(P)$ of $0.6$ $pu$ to the bus. Assume the infinite bus ... $pu$. Neglect stator resistance. The reactive power $(Q)$ in $pu$ supplied by the generator to the bus under this condition is _________.
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee2
infinitebus
realpower
numericalanswers
0
votes
0
answers
22
GATE2014215
A three phase starconnected load is drawing power at a voltage of $0.9$ $pu$ and $0.8$ power factor lagging. The three phase base power and base current are $100$ $MVA$ and $437.384$ $A$ respectively. The linetoline load voltage in $kV$ is ________.
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee2
powerfactor
starconnection
numericalanswers
0
votes
0
answers
23
GATE2015116
Consider a HVDC link which uses thyristor based linecommutated converters as shown in the figure. For a power flow of $750$ MW from System $1$ to System $2$, the voltages at the two ends, and the current, are given by: $V_{1} = 500 kV, V_{2} = 485 kV$ and $I = 1.5 kA$. If the direction ... $I= −1.5 kA$ $V_{1} = −500 kV, V_{2} = −485 kV$ and $I = −1.5 kA$
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2015ee1
hvdclines
powerflowanalysis
0
votes
0
answers
24
GATE2016240
At no load condition, a $3$phase, $50$ Hz, lossless power transmission line has sendingend and receivingend voltages of $400$ kV and $420$ kV respectively. Assuming the velocity of traveling wave to be the velocity of light, the length of the line, in km, is ____________.
asked
Jan 30, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2016ee2
losslesspowertransmissionline
travelingwave
numericalanswers
0
votes
0
answers
25
GATE201353
In the following network, the voltage magnitudes at all buses are equal to $1 p.u.$, the voltage phase angles are very small, and the line resistances are negligible. All the line reactances are equal to $j1$ $\Omega.$ If the base impedance and the linetoline ... respectively, then the real power in $MW$ delivered by the generator connected at the slack bus is $10$ $0$ $10$ $20$
asked
Feb 12, 2017
in
Power Systems
by
piyag476
(
1.5k
points)
gate2013ee
powerflowanalysis
buses
0
votes
0
answers
26
GATE2014220
While measuring power of a threephase balanced load by the twowattmeter method, the readings are $100$ $W$ and $250$ $W$. The power factor of the load is ______.
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee2
balancedloads
powerfactor
numericalanswers
0
votes
0
answers
27
GATE2014131
In an unbalanced three phase system, phase current $I_a=1\angle (90^{\circ})\: \text{pu}$ , negative sequence current $I_{b2}=4\angle (150^{\circ})\: \text{pu}$, zero sequence current $I_{c0}=3\angle 90^{\circ}\: \text{pu}.$ The magnitude of phase current $I_b$ in $\text{pu}$ is $1.00$ $7.81$ $11.53$ $13.00$
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee1
unbalancedsystem
sequencenetworks
0
votes
0
answers
28
GATE2014143
The overcurrent relays for the line protection and loads connected at the buses are shown in the figure. The relays are $IDMT$ ... setting for relay $R_B$ to be $0.1$ and $5A$ respectively, the operating time of $R_B$ (in seconds) is ______________
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee1
overcurrent
relays
line
protection
numericalanswers
0
votes
0
answers
29
GATE2014145
The Bode magnitude plot of the transfer function $G(s)=\dfrac{K(1+0.5s)(1+as)}{s(1+\frac{s}{8})(1+bs)(1+\frac{s}{36})}$ is shown below: Note that $6dB/octave = 20 dB/decade.$ The value of $\dfrac{a}{bK}$ is ________.
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee1
bodeplot
feedbacksystem
numericalanswers
0
votes
0
answers
30
GATE2015122
The self inductance of the primary winding of a single phase, $50$ Hz, transformer is $800$ mH, and that of the secondary winding is $600$ mH. The mutual inductance between these two windings is $480$ mH. The secondary winding of this transformer is short circuited ... neglected. In this condition, what is the effective inductance (in mH) seen by the source? $416$ $440$ $200$ $920$
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2015ee1
selfinductance
sinusoidalvoltagesource
0
votes
0
answers
31
GATE2016241
The power consumption of an industry is $500$ kVA, at $0.8$ p.f. lagging. A synchronous motor is added to raise the power factor of the industry to unity. If the power intake of the motor is $100$ kW, the p.f. of the motor is ___________.
asked
Jan 30, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2016ee2
synchronousmotor
powerfactor
powerintake
numericalanswers
0
votes
0
answers
32
GATE2014328
The function $f(x)=e^x1$ is to be solved using NewtonRaphson method. If the initial value of $x_0$ is taken as $1.0$, then the absolute error observed at $2^{nd}$ iteration is _______.
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee3
linelosses
iterativemethod
numericalanswers
0
votes
0
answers
33
GATE2016141
A $30 MVA$, $3$phase, $50 Hz$, $13.8 kV$, starconnected synchronous generator has positive, negative and zero sequence reactances, $15$%, $15$% and $5$% respectively. A reactance $(X_{n})$ is connected between the neutral of the generator and ground. A double ... $X_{n}$ (in p.u.) that will limit the positive sequence generator current to $4270$ A is ________.
asked
Jan 30, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2016ee1
slip
powersystemfaults
sequencenetworks
numericalanswers
0
votes
0
answers
34
GATE201333
For a power system network with $n$ nodes, $Z_{33}$ of its bus impedance matrix is $j0.5$ per unit. The voltage at node $3$ is $1.3\angle 10^{\circ}$ per unit. If a capacitor having reactance of $j3.5$ per unit is now added to the network between node $3$ and the ... unit is $0.325\angle 100^{\circ}$ $0.325\angle 80^{\circ}$ $0.371\angle 100^{\circ}$ $0.433\angle 80^{\circ}$
asked
Feb 12, 2017
in
Power Systems
by
piyag476
(
1.5k
points)
gate2013ee
busimpedancematrix
source
0
votes
0
answers
35
GATE2014324
A nonideal voltage source $V_s$ has an internal impedance of $Z_s$. If a purely resistive load is to be chosen that maximizes the power transferred to the load, its value must be $0$ real part of $Z_s$ magnitude of $Z_s$ magnitude of $Z_s$
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee3
nonidealvoltagesource
resistiveload
0
votes
0
answers
36
GATE2014241
There are two generators in a power system. Noload frequencies of the generators are $51.5$ $Hz$ and $51$ $Hz$, respectively, and both are having droop constant of $1$ $Hz$/$MW$. Total load in the system is $2.5$ $MW$. Assuming that the generators are operating under their respective droop characteristics, the frequency of the power system in $Hz$ in the steady state is ___________.
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee2
powersystemanalysis
powerproduction
numericalanswers
0
votes
0
answers
37
GATE2014139
A three phase synchronous generator is to be connected to the infinite bus. The lamps are connected as shown in the figure for the synchronization. The phase sequence of bus voltage is $RYB$ ... bus same as infinite bus and its frequency is more than infinite bus same as infinite bus and its frequency is less than infinite bus
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
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gate2014ee1
infinite
bus
synchronization
0
votes
0
answers
38
GATE2014142
The fuel cost functions of two power plants are Plant $P_1 : C_1=0.05Pg_1^2+APg_1+B$ Plant $P_2 : C_2=0.10Pg_2^2+3APg_2+2B$ where, $P_{g1}$ and $P_{g2}$ are the generated powers of two plants, and $A$ and $B$ are the constants. If the two plants optimally share $1000\:MW$ load ... cost of $100$ $Rs/MWh$, the ratio of load shared by plants $P_1$ and $P_2$ is $1:4$ $2:3$ $3:2$ $4:1$
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee1
power
plants
powergeneration
0
votes
0
answers
39
GATE2016140
A threephase cable is supplying $800 kW$ and $600 kVAr$ to an inductive load. It is intended to supply an additional resistive load of $100 kW$ through the same cable without increasing the heat dissipation in the cable, by providing a threephase bank of ... the line voltage is $3.3 kV$, $50 Hz$, the capacitance per phase of the bank, expressed in microfarads, is ________.
asked
Jan 30, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2016ee1
activepower
reactivepower
heatlosses
numericalanswers
0
votes
0
answers
40
GATE201436
The line $A$ to neutral voltage is $10\angle 15^0$ for a balanced three phase starconnected load with phase sequence $ABC$. The voltage of line $B$ with respect to line $C$ is given by $10\sqrt{3}\angle 105^0$ $10\angle 105^0$ $10\sqrt{3}\angle 75^0$ $10\sqrt{3}\angle 90^0$
asked
Feb 12, 2017
in
Power Systems
by
makhdoom ghaya
(
9.2k
points)
gate2014ee3
balancedthreephaseline
sequencenetworks
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