Thursday 4 March 2021

Makaut(WBUT) 7th Sem Electrical Engineering (Power System III) Previous Year and Chapter Wise MCQ ⚡

Makaut(WBUT) 7th Sem Electrical Engineering Previous Year Question and Chapter Wise MCQ

👉SUBJECT----
📗   ELECTRIC DRIVE (EE-701)
📕   UTILIZATION OF  ELECTRIC POWER (EE-702)
📘   POWER SYSTEM - III (EE-703)
📙    RENEWABLE & NON-CONVENTIONAL ENERGY (EE-704)
📗   COMPUTER NETWORK (EE-705)

POWER  SYSTEM-III

ECONOMIC OPERATION OF ENERGY GENERATION SYSTEM
[Multiple Choice Type Questions]

1. Unit of regulation of speed governor is   [WBUT 2009]
a)Hz/MW   b)MW/Hz    c)Unit less   d)km/sec
Answer: (b)

2.The unit of transmission loss coefficient is   [WBUT 2009]
a)MW    b)(MW)^-1   c)(Mw)^-2    d) unit less   e)  None of these
Answer: (b)

3.If penalty factor of a plant is unity,its incremental transmission loss is  [WBUT 2009, 2016]
a) 1.0   b)-1.0  c) 0.0  d)2.0
Answer: (c)

4.A generating unit has as incremental production cost of Rs,60 per MWh. If the penalty factor for this unit is 1.2, the incremental cost of power delivered is   [WBUT 2010,2017]
(a)Rs.50 per Mwh  (b)Rs.72 per Mwh  (c)Rs.61.20 per Mwh  (d)Rs.48 per MWh
Answer: (a)

5.In a two plant system, the load is connected to plant no. 2. The loss coefficients [WBUT 2010] 
a)B11,B12,B22 are non-zero
b)B11 is non-zero but B12 and B22 are zero
c)B11 and B12 are non-zero but B22 is zero 
d)B11 and B12 are non-zero but B12 is zero
Answer:(b)

6.The unit of B-coefficient is  [WBUT 2010]
a)MW      b)MW^-1      c)Pure Number    d)None of these
Answer:(B)

8.ln a power station the cost of generation of power reduces most effectively when [WBUT 2011]
a)Diversity factor alone increases
b)Load factor atone increases
c)Both diversity and load factor increase
d)Both diversity and load factor decrease
Answer: (c)

9.Spinning reserve is [WBUT 2011] 
a)a part of the UCP                            
b)the difference between all unit productions to present load with losses
c)the difference between all unit productions to present load
d)None of these
Answer:(C)

10.The incremental cost characteristics of the two units in a plant are given by Ic1=Rs(0.1Pi + 8.0) per MWh and lc2 =Rs(0.15P2 + 3.0) per MWh. The optimum sharing of load by two generators when the total load is 100 MW, are                                                                               [WBUT 2012]
a)Pi = 60 MW and P2 = 40MW       b)Pi = 33.3 MW and  P2 = 66.7 MW
c)Pi = 40 MW and P2 = 60 MW      d)Pi = 66..7 MW and P2 = 33.3 MW
Answer:(c) 

12.The penalty factor   [WBUT 2012]
a)is always less than 1               b)is always more than 1
c)may be more or less than 1   d) is equal or less than 1
Answer: (d)

13.statement is true  [WBUT2014]
a)peak diversity factor and group diversity factor are always equal
b)peak diversity. factor always less than group diversity factor
c)peak diversity factor cannot be less .than group diversity factor
d)peak diversity factor may be more or less than group diversity factor
Answer: (b)

14.A generating unit has an incremental production cost of Rs.60.00 per MWh. If penalty factor for this unit is 1.2, what is the incremental cost of power? [WBUT 2015]
a) Rs.120.00 b) Rs.72.00 c) Rs.50.00 d) Rs.12.00
Answer: (c)

15.For economic measure in Power system, the generators of a power plant should operate at  [WBUT 2016]
a)equal loads  b) minimum loads   c) load proportional to the rating   d) equal incremental cost
Answer: (d)
 
16.The unit of Lagrange MultiPlier '  λ  ' used in economic dispatch solution is  [WBUT 2016]
a)Rs/hr b) Rs/MW  c) Rs/MWh  d) Rs/Mwh                                                        
Answer: (c)

17.Economic operation of  power system is carried out on the basis of  [WBUT 2017]
a)equal incremental fuel cost     b)equal area criterion
c) equal fuel cost                          d)all units sharing equal power
Answer: (a)

AUTOMATIC GENERATION CONTROL
[Multiple Choice Type Questions]

1.In AGC, the  Voltage and frequency is controlled by [WBUT 2009, 2017]
a)excitation control
b)turbine control
c)turbine speed control and turbine speed control respectively
d)excitation control and turbine speed control respectively  
Answer: (d) 

2.A synchronous condenser is a [WBUT 2009]
a)Synchronous generator b) Paper condenser
c)Synchronous motor       d)none of these
Answer: (c)

3.synchronous condenser is a/an  [2010, 2013, 2014]
a)d.c. generator                                   b)induction motor
c)overexcited synchronous motor     d) under excited synchronous motor
Answer: ( C )

4.For increasing the reactive power output of a synchronous generator [WBUT 2011, 2017]
a)field current has to be reduced
b) field current has to be increased  
c)generator speed has to be increased
d)generator speed has to be decreased
Answer: (b)

5.If the speed regulation is 5% and the rated frequency is 6oHz, then change in frequency  is [WBUT 2011]
a)3 Hz b) 6 Hz c) 5 Hz d) none of these
Answer:(a)
 
6.With  the motor load increase in supply frequency, power consumption of an induction [WBUT 2011]
a)decreases 
c)remains unchanged 
b)increases.
d)depends upon the motor winding connection
Answer: (a)

7.Unit of regulation for AGC is . . . (WBUT 2012, 2013]
a) MW/Hz  b) unit-less c) Hz/MW  d) r.p.s.
Answer: (a)

8.AGC is done by taking [WBUT 2012]
a)feedback  of frequency from o/p generator  
b)feedback of excitation 
c)feedback of frequency from o/p generator
d)feedback of frequency from load
Answer: (d)
 
9.A power system needs injection of VARs [WBUT 2012]
a)at peak loads
b)at off-peak load
c)both at peak load and off-peak load
d)when the load is neither too high nor too low 
Answer: (a)
 
10.Tie-line bias control is used to [WBUT 2012]
a)increase power exchange capacity through tie-line
b)decrease power exchange capacity through tie-line
c)minimize steady-state frequency deviation
d)both (a) and (c)
Answer: (c)
 
11.Load frequency control is achieved by properly matching the individual machine's[WBUT 2013]                                                                                            
a)reactive power b)  generated  power
c)turbine input  d) turbine and generator relays
Answer:(c)

12.The units of speed regulation of governor are [WBUT 2014]
a)Hz b)Hz per MVA c) Hz per MW d) None of these
Answer: (c)
 
13 The optimal scheduling Problem in the case of a thermal power plant is [WBUT 2014] 
a)static optimization problem
b)dynamic optimization problem
c)static as well as dynamic optimization problem
d)none of these
Answer: (a) 

14.In the ALFC loop,incremental frequency can be reduced using_______ controller. [WBUT 2014]
a)differential  b)integral c)proportional d) all of these
Answer: (b)
 
15.Dynamic response in a two-area system may be represented by a_______ order Transfer Function. [WBUT 2014]
a) first  b) second c)  third d) none of these
Answer: (b)

16.When a long transmission line is supplying peak load  [WBUT 2014]
a) shunt capacitance and charging current predominate  
b) the inductance of the line results in substantial voltage drop 
c) the resistance of the line causes large voltage drop 
d) voltage regulation may be negative 
Answer: (b) 

17.What is the unit of regulation in an AGC system? [WBUT 2015]
a) Hz/MW  b) MW/Hz  c) unit less  d) MW/Sec
Answer: (b) 

18.Which device is suitable to operate as a synchronous condenser? [WBUT 2015] 
a) synchronous generator  
b) Squirrel-cage induction motor 
c) under-excited synchronous motor 
d) over-excited synchronous moto
Answer:(d)

19.Two neighboring Power System network having different frequencies may be interconnected through  [WBUT 2015] 
a)800 KV HVDC link  b)400 KV AC link 
c)765 KV AC link        d) 1200 KV AC link 
Answer: (a) 

20.The ownership and coordination of Transmission and Grid Management under 
Deregulation must be  ··  [WBUT 2015] 
a) Government Monopoly 
b) Government and Private Operation 
c) Government, Private and Retail Operation 
d) Private Monopoly. 
Answer: (b) 

21.Steady-state stability of the power system is improved by [WBUT 2016] 
a) reducing fault clearing time 
b) using double circuit line instead of single circuit line 
c) single-pole switching 
d) decreasing generation inertia 
Answer:(b) 

22.AVR loop is assigned to control [WBUT 2016]
a) terminal voltage of generator   b) frequency 
c) reactive power                          d) real power output 
Answer: (a) 

 HIGH VOLTAGE AC & DC POWER TRANSMISSION  
[Multiple Choice Type Questions]

1.The highes transmission voltage used in india is [WBUT 2009]
a) 400 kV  b) 220 kV c) 132 kV   d) 765 kV
Answer: (d)  
 
2.Ferranti effect happens in transmission line when the line is  [WBUT 2009 2013] 
a) short and loaded   b)long and loaded 
c) long and unloaded   d) None of these
Answer: ( c)    
 
3. What is the suitable condition for Ferranti Effect to occur in a transmission line? [WBUT 2015]  
a) long and unloaded line        b) long and loaded line 
c) short length and loaded line  d) medium length unloaded line
Answer: (a) 

4. Two neighboring power system networks, having different frequencies, may be 
interconnected through  [WBUT 2016] 
a) 800 kV HVDC  b) 400 kV AC link 
c) 765 kV link       d) 1200 kV AC link 
Answer: (d) 

COMPENSATION IN POWER SYSTEM
[Multiple Choice Type Questions]

1.Load compensation is used to improve [WBUT 2010, 2017]
a) voltage profile and power factor
b) voltage profile and reactive power
c) reactive power and power factor
d) None of these
Answer: (b)
 
2.An uncompensated transmission line on open circuit leads to [WBUT 2010, 2017]
a)Ferranti effect
b) Line-charging current flowing into generators is more
c) Both (a) & (b)
d) None of these
Answer: (c)
 
3.Series compensation in transmission lines [WBUT 2010, 2011, 2017]
a) increases stability limit          b) decreases stability limit
c) has no effect on stability limit d) none of these
Answer: (a)

 
4.steady-state stability of the power system Is Improved by [WBUT 2010]
a)reducing fault clearing line
b)using double circuit line instead of single circuited line
c)single-pole switching
d) decreasing generation inertia
Answer: (b)

5.TCSC is a
a) shunt controller  b) series controller 
c) combination of (a) & (b)  d) none of these
Answer: (c) 

6.Shunt compensation in an EHV is resorted to 
a) improve the stability   
b) reduce the fault level 
c) improve the voltage profile 
d) as a substitute for synchronous phase modifier
Answer:(c)

7.The state variables in a power system are  [WBUT 2013, 2014] 
a) voltage and current
b) voltage and phase angle 
c) current and Phase angle 
d) reactive power and active power 
Answer: (b) 

8. The reactive power transfer over a line mainly depends on  [WBUT 2014, 2016] 
a) power angle  b) sending end voltage Vs 
c) receiving end voltage Vr  d) │Vs│-│Vr│
Answer: (d) 

9.What is the main function of series compensation in Transmission Lines? [WBUT 2015] 
a) to prevent Ferro-Resonance    b) to improve power factor 
c) to enhance stability limit  d) to prevent Ferranti effect 
Answer: (c) 

10.Series compensation in EHV line is used to  [WBUT 2015] 
a) improve voltage profile     b) reduce fault level 
c) improve efficienicy      d) reduce power factor 
Answer: (c) 

11. With the help of a reactive compensation, it is possible to have [WBUT 2016]
a) constant voltage operation only 
b) unity power factor operation only 
c) both constant voltage & unity power factor 
d) either constant voltage or unity power factor 
Answer: (d) 


POWER SYSTEM TRANSIENTS 
[Multiple Choice Type Questions]

1.The characteristics impedance of 250 km long overhead line is 400 ohms. For a line of 200 km length of the same line, the characteristics impedance will be  [WBUT 2009] 
a) 50 ohms  b) 400 ohms  c) 200 ohms  d) 800 ohms 
Answer: (b) 

2.The transient phenomenon lasts in a power system for a period ranging from   [WBUT 2009, 2012, 2017] 
a)few ms to 1s    b)1s to 2s 
c) 2s to 3s           d)greater than 3 seconds 
Answer: (a) 

3. An overhead transmission line is provided with earth wire for protection against  [WBUT 2009, 2017] 
a) switching surge                           b) lighting surge 
c) power frequency overvoltage    d) None of these  
Answer:(b) 

4. A valve type lightning arrestor in a substation should be placed  [WBUT 2009] 
a) closed to the circuit brake  b) close to the transformer 
c) away from the transformer  d) None of these 
Answer: (b) 

5. Lightning arrester should be located  [WBUT 2010, 2017] 
a) near the circuit breaker        c) near the transformer 
b) away from the circuit breaker   d) away from the transformer 
Answer: ( c) 

6.The propagation constant is given by  [WBUT 2010, 2013] 
a) γ= √(Z/Y)  b)γ= √(ZY)  c) γ= √(Z+Y)  d) γ= √(Z-Y) 
Answer: (b) 

7. For a line terminated by a load having resistance as characteristic impedance of line 
[WBUT 2011] 
a) there is no reflected wave. 
b) transmitted current wave is twice the reflected wave 
c) transmitted voltage wave is twice the reflected wave 
d) incident current wave is twice the reflected wave 
Answer: (c) 

8.Steady-state stability of the  Power system is improved by  [WBUT 2011]
a) reducing fault clearing  
b) using double circuit line instead of single circuited line
c) single-pole switching
d) decreasing generation inertia 
Answer: (b) 

9.In an open circuited transmission line, the voltage developed at the open end 
due to surge voltage ef is  [WBUT 2011] 
a) 4ef  b) 2ef  c) 1.5ef  d) ef
Answer: (b) 

10.Earth wire on overhead transmission line is provided to protect the line against  [WBUT 2011] 
a) Lightning surge b) Switching surge 
c) Excessive fault voltages d) corona effect
Answer: (a)  
 
11. An overhead transmission line having inductance L H/km and capacitance C F/km, the characteristic impedance of the line is given by  [WBUT 2012] 
a) LC  b)L/C  c) C/L  d) 1/LC 
Answer: (b) 

12. The capacitance and inductance per unit length of a line operating at 110 kV are   0.1 µF and 2 mH respectively. The surge impedance of the line is [WBUT 2010, 2013, 2017] 
a) 40 MVA b) 30 MVA  c) 25 MVA d) None of these 
Answer: (d) 

13. For a long uncompensated line, the limit to the line loading is governed by  [WBUT 2013, 2016] 
a) thermal limit  b) voltage drop
c) stability limit  d) corona loss 
Answer: (c) 
 

14. The coefficient of reflection for current for an open ended line is  [WBUT 2010]
a) 1.0  b) 0.5    c)-1.0   d) 0
Answer: (a) 

15.A valve-type lightning arrestor ins substation should be placed. [WBUT 2013] 
a) close to the circuit breaker  b) away from the circuit breaker 
c) close to the transformer  d) away from the transformer  
Answer: (c)

16.The reflection coefficient for the voltage wave in overhead transmission lines is given as [WBUT 2014]
a)Ro/Ro-RL b)RL/Ro-RL  c)RL-Ro/RL+Ro  d)RL+Ro/Ro-RL
Answer:(C) 

17.Statistically which type of cloud causes more stroke?  [WBUT 2014] 
a) negatively charged    b) positively charged 
c) both equal  d) unpredictable 
Answer: (a)

18.The transient phenomenon lasts in power system for how much time?  [WBUT 2015] 
a) a few microseconds only  b) a few milliseconds to one second 
c) a few minutes  d) instantaneous only 
Answer:(a) 

19.An overhead transmission line is provided with earth wire for protection against which type of disturbance?                                                                                                                        [WBUT 2015]
a) switching surge  c) lighting surge 
b) traveling wave   d) Ferro-resonance 
Answer:(c) 

20.The characteristic impedance of a 250 km line is 400 ohms. what is the characteristic impedance of 200 km length of the same line?  [WBUT 2015]  
a)320 ohms  b) 500 ohms 
c)200 ohms  d) 400 ohms 
Answer: (d)

21.A trayelling wave 400 x 1 x 50 means crest value of  [WBUT 2016] 
a) 400 V with rise time of 1 /50 sec 
b) 400 kV with rise time 1 sec & fall time 50 sec 
c) 490 kV with rise time 1 µ sec & fall time for 1/2 the crest value 50 µsec 
d) 400 MV with rise time 1 µsec & fall time S0 µsec 
Answer:(D) 

22.When a DC source is switched on a purely inductive  circuit, the  circuit response is 
[WBUT 2016] 
a)an exponentially rising curve
b) an exponentially decaying curve 
c) a straight line passing through the origin 
d) a straight line off-set from the origin 
Answer: (a)

23.If a is the angle of voltage wave at which an R-L circuit is switched on and 0 is the impedance angle of the R-L circuit, there will be no transient when the circuit is switched on, if[WBUT 2016] 
a) α =0        b) a = 90° - θ
c) α = 90° + θ     d) none of these 
Answer: (b)  

24. Permissible change in power frequency is. [WBUT 2017] 
a) 0.5 Hz   b) 1 Hz   c) 5 Hz d) 10 Hz 
Answer: (a)  

POWER STATIONS
[Multiple Choice Type Questions]

1.The generating station suitable to operate as peak load plant is  [WBUT 2009, 2011]
a) Thermal Power Station   
b) Nuclear Power Station 
c) Pumped Storage Power Station 
d) None of these  
Answer:(c) 




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