Cmps Paper Objective Paper

UNIT-1Bottom of Form1. If A=AT then the matrix is (A)Symmetrical (B)Skew-symmetric

(C)Hermitian(D)Skew-hermitian

2. If A,BandCare matrices with orders 33, 23 and 42 respectively, how many of the following matrix calculations are possible?4B,A+B, 3BT+C,AB,BTA, (CB)T,CBA(A)1(B)2

(C)3(D)0

3. IfA=andB=find the matrixXwhich satisfies the matrix equation

2A+XT= 3B.(A)(B)

(C)(D)

4. The matrixhas determinant, 1 -a+at. Use Cramer's rule to solve the following system of equation for C.

(A)(B)

(C)(D)

5. One unit of I1 uses 0.2 units of I1 and 0.6 units of I2. One unit of I2 uses 0.4 units of I1 and 0.2 units of I2. Find the associated Leontief inverse.(A)(B)

(C)(D)

6. For the commodity marketC=aY+bandI=cr+dFor the money marketMS=MS*andMD=k1Y+k2r+k3If both markets are in equilibrium, find the matrixAsuch thatAx=bwherex=andb=(A)(B)

(C)(D)

7. Find the cofactor,A23, of the matrixA=(A)0(B)7

(C)-7(D)23

8. Find the determinant of the matrix

(A)14(B)340

(C)364(D)100

9. Find the value ofaif the following matrix is singular

(A)0(B)3

(C)-3(D)-1/3

10. Which one of the following matrices has an inverse which is not listed?

A=, B=, C=, D=, E=(A)A(B)B

(C)C(D)D

11. Find AB if (A)(B)

(C)AB is undefined(D)

12. Find A-1, if

13. Determine whether or not the matrices are inverse of each other.

(A)Yes(B)No

14. Determine whether the matrix is invertible

(A)Yes(B)No

15. Compute the determinant of the matrix by cofactor expansion

(A)No(B)Yes

(C)(D)

16. If A=-AT then the matrix is (A)Symmetrical (B)Skew-symmetric(B)

(C)Hermitian(D)Skew-hermitian(D)


(A)1084(B)286

(C)-286(D)146


(A)0(B)-80

(C)80(D)-40

19. Compute the determinant of the matrix by cofactor expansion.

(A)-9(B)-36

(C)0(D)36


(A)-200(B)100

(C)-100(D)-50

21. If A= (A*)T then the matrix is (A)Symmetrical (B)Skew-symmetric(B)


22. If A= -(A*)T then the matrix is (A)Symmetrical (B)Skew-symmetric(B)


23. Which one of the following matrices reveals the topology of the power system network?(A)Bus incidence matrix(B)Primitive impedance matrix

(C)Primitive admittance matrix(D)Bus impedance matrix

24. The equivalent Thevenins bus admittance matrix of a two-bus system with identical generators on both buses is The generator reactance and interconnected line reactance will be respectively(A)j0.05 & j0.1(B)-j0.05 & j0.1

(C)-j0.05 & -j0.1(D)j0.1 & j0.05

UNIT-2

1. The bus admittance matrix of the network shown in the given figure, for which the marked parameters are pu impedances, is

(A)(B)

(C)(D)

2. A power system network consists of three elements 0-1, 1-2, 2-0 of pu impedances 0.2, 0.4 and 0.4 respectively. Its bus impedance matrix is given by(A)(B)

(C)(D)

3. Zbus for the following system is

(A)(B)

(C)(D)None of these

4. Ybus for the following system is:-(impedance is given)

(A)(B)

(C)(D)None of these


(A)(B)

(C)(D)None of these


(A)(B)

(C)(D)

7. Determine Zbus for the following system is

(A)Zbus=[j0.05](B)

(C)(D)Any of the above

8. Ybus for the following system is

(A)(B)

(C)(D)Any of the above

9. Ybus for the following system is Bottom of Form

(A)(B)

(C)(D)None of these

10. Ybus for the following system isBottom of Form

(A)(B) Bottom of Form

(C)(D)


(A)(B)

(C)(D)


(A)(B)

(C)(D)

13. Find Ybus for the following system is

(A)(B)

(C)(D)

14. Find Zbus for the following system is

(A)(B)

(C)(D)


(A)(B)

(C)(D)

16. Find Zbus for the following system is

(A)(B)

(C)(D)


(A)(B)

(C)(D)

18. Normally ZBUS matrix is a (A)Null matrix(B)Sparse matrix

(C)Full matrix(D)Unity matrix

19. If and I=AIs where I is equal to phase current vector, and IS is equal to symmetrical current vector, then which one of the following matrices is the symmetrical components transformation matrix A?

(A)

(B)

(C)

(D)

20. is the pe unit impedance on the power base and voltage base . What would be the per unit impedance on the new power base ?(A)

(B)

(C)

(D)

UNIT-3

1. For measuring positive, negative and zero sequence voltages in a system, the reference is taken as:(A)Neutral of the system only(B)Ground only

(C)For zero sequence neutral and for positive and negative the ground(D)None of the above

2. A shunt fault is characterized by:(A)Increase in current, frequency and p.f.(B)Increase in current, reduction in frequency and p.f.

(C)Increase in current, frequency and reduction in p.f.(D)None of the above

3. if Ia1 is the positive sequence current of an alternator and Z1, Z2 and Z0 are the sequence impedances of the alternator. The drop produced by the current Ia1 will be:(A)Ia1Z1(B)Ia1(Z1+Z2)

(C)Ia1(Z1+Z2+Z0)(D)Ia1(Z2+Z0)

4. For the system shown in diagram below, a LG fault on the line side of the transformer is equivalent to

(A)A LG fault on the generator side of the transformer(B)A LL fault on the generator side of the transformer

(C)A LLG fault on the generator side of the transformer (D)A LLL fault on the generator side of the transformer

5. Zero sequence currents can flow from a line into a transformer bank if the windings are in(A)Grounded star/delta(B)Delta/star

(C)Star/star grounded(D)Delta/delta

6. Consider the following statement regarding the fault analysis:i) The neutral grounding impedance Zn appears an 3Zn in zero sequence equivalent circuits.ii) For faults on transmission lines, 3-phase fault is the least severe amongst other faults.iii) The positive and negative sequence networks are not affected by method of neutral grounding.Which of the statements given above are correct?(A)2 and 3(B)2 and 1

(C)1 and 3(D)1, 2 and 3

7. If a sudden short circuit occurs on a power system (considered as R-L series circuit), the current wave-form consists ofi) A decaying a.c. currentii) A decaying d.c. current.Let the alternator reactance be X and the power system resistance R. which one of the following is correct?

(A)The decay in (1) is caused by the increase in X but in (2) is caused by R(B)The decay in (1) is caused by the increase in R but in (2) is caused by X

(C)The decay in both (1) and (2) is caused by R(D)The decay in both (1) and (2) is caused by increase in X

8. Steady state operating condition of a power system indicates(A)A situation when the connected load is absolutely constant(B)A situation when the generated power is absolutely constant

(C)A situation when both connected load and generated power are equal to each other and remain constant.(D)An equilibrium state around which small fluctuations in power, both in generation and load, occur all the time

9. In a power system, the 3-phase fault MVA is always higher than the single-line-ground fault MVA at bus(A)True(B)False

(C)Cant be determined(D)

10. For a fault at the terminal of a synchronous generator, the fault current is maximum for a Bottom of Form11. (A)3-phase fault(B)3-phase to ground fault

(C)Line-to-ground fault(D)Line-to-line fault

11. For an unbalanced fault, with paths for zero sequence currents, at the fault point(A)The negative and zero sequence voltages are minimum(B)The negative and zero sequence voltages are maximum

(C)The negative sequence voltage is minimum and zero sequence voltages are maximum(D)The negative sequence voltage is maximum and zero sequence voltages are minimum

12. The sequence components of the fault current are as follows: Ipositive=j1.5pu, Inegative= -j0.5pu, Izero= -j1.0pu. the type of fault in the system is(A)LG(B)LL

(C)LLG(D)LLLG

13. for a three phase to ground fault is(A)(B)

(C)(D)Not defined

14. for a three phase to ground fault is(A)(B)Where

(C)(D)


(C)(D)Not defined


(C)(D)

17. for a three phase fault is(A)(B)

(C)(D)Not defined

18. for a three phase fault is(A)(B)Where

(C)(D)


(C)(D)Not defined


(C)(D)

21. for a double phase to ground fault is(A)(B)

(C)(D)Not defined

22. for a double phase to ground fault is(A)(B)Where

(C)(D)


(C)(D)Not defined


(C)(D)

25. for a single phase to ground fault is(A)(B)

(C)(D)Not defined

26. for a single phase to ground fault is(A)(B)Where

(C)(D)


(C)(D)Not defined


(C)(D)

29. for a double phase fault is(A)(B)

(C)(D)Not defined

30. for a double phase fault is(A)(B)Where

(C)(D)


(C)(D)Not defined


(C)(D)

UNIT-4

1. In load flow studies of a power system, the quantities specified at a voltage controlled bus are _____ and ______.(A)(B)

(C)V, I(D)

2. In load flow analysis, the load connected at a bus is represented as(A)Constant current drawn from the bus(B)Constant impedance connected at the bus

(C)Voltage and frequency dependent source at the bus(D)Constant real and reactive power drawn from the bus

3. In load flow analysis, a voltage controlled bus is treated as in subsequent iteration for a reactive power limit is violated (A)True(B)False

(C)Cant be determined(D)

4. If reference bus is changed in two load flow runs with same system data and power obtained for reference bus taken as specified P & Q in the later run(A)The system losses will be unchanged but complex bus voltage will change(B)The system losses will change but complex bus voltage remains unchanged

(C)The system losses as well as complex bus voltage will change(D)The system losses as well as complex bus voltage will be unchange

5. The per unit voltage of two synchronous machines connected through a lossless line are 0.95 and 1.0. Match the two sides of the following(a)Real power of machine 1(p)Positive real power

(b)Reactive power of machine 1(q)Positive reactive power

(c)Power factor of machine(r)Negative real power

(s)Negative reactive power

(t)Leading power factor

(u)Lagging power factor

(A)a-p, b-s, c-u(B)a-p, b-r, c-u

(C)a-q, b-r, c-t(D)a-p, b-s, c-t

6. Two transposed 3- lines run parallel to each other. The equation describing the voltage drop in both lines given below

Compute the self and mutual zero sequence impedances of this system i.e. complete Z011, Z012, Z021, Z022 in the following equation V01=Z011I01+ Z012I02V02=Z021I01+ Z022I02Where V01, V02, I01, I02 are the zero sequence voltage drops and currents for the two lines repectively.(A)Z011= Z022=j0.59, Z012=Z021 =j0.44(B)Z011= Z022=j0.37, Z012=Z021 =j0.22

(C)Z011= Z022=j0.25, Z012=Z021 =j0.10(D)Z011= Z022=j0.59, Z012=Z021 =j0.22

7. A power system consists of 2 areas connected by a single tie line. It is required to carry out a load flow study on this system. While entering the network data, the tie line data is inadvertently left out. If the load flow program is run with this incomplete data.(A)The load flow will converge only if the slack bus is specified in area 1(B)The load flow will converge only if the slack bus is specified in area 1

(C)The load flow will converge only if the slack bus is specified in either area 1 or area 2(D)The load flow will not converge only if only one slack bus is specified

8. A power system consist of 300 buses out of which 20 buses are generator bus, 25 buses are one with reactive power support and 15 buses are the one with fixed shunt capacitors. All the other buses are load buses. It is proposed to perform a load flow analysis in the system using N-R jacobian matrix is(A)553 X 553(B)540 X 540

(C)555 X 555(D)554 X 554

9. The positive, negative and zero sequence impedances of a solidly grounded system under steady state condition always follow the relations:

(A)Z1>Z2>Z0 (B)Z1Z2(D)None of the above

10. Buses for load flow studies are classified as (i) the load bus, (ii) the generator bus and (iii) the slack busThe correct combination of the pair of quantities specified having their usual meaning for different buses is

11. in the solution of load flow equation, NR method is superior to the GS method, because the (A)Time taken to perform one iteration in the NR method is less when compared to the time taken in the GS method(B)Number of iteration required in the NR method is less when compared to that in the GS method

(C)Number of iteration required is not independent of the size of the system in the NR method(D)Convergence characteristic of the NR method are not affected by the selection of slack bus

12. Consider the following quantities:1Real power2Reactive power

3Power factor4Input current

5Bus voltage magnitude6Bus voltage phase angle

For the purpose of the load flow studies of a power system, each bus or node is associated with which one of the combination of above four quantities(A)1,3,4 & 5(B)1,2,3 &4

(C)2,3,5,& 6(D)1,2,5 & 6

13. At slack bus, which one of the following combinations of variables is specified?(A)(B)P,Q

(C)(D)

14. A voltage controlled bus is characterized by the specified(A)Real and reactive powers(B)Real powers and voltage phase angle

(C)Real power and voltage magnitude(D)Reactive power and voltage magnitude

15. Consider the following statement:Transient stability of a synchronous generator feeding power to an infinite bus through a transmission line can be increased byi) Increasing the steam supply to the turbine driving the generator during fault clearing.ii) Connecting resistors at the generator terminals during fault condition.iii) Employing a faster excitation system.iv) Quickly throwing off the generator load.Which of these statements are correct?(A)2 and 3(B)3 and 4

(C)1 and 2(D)2 and 4

16. In Gauss-Siedel method of power flow problem, the number of iterations may be reduced if the correction in voltage at each bus is multiplied by

(A)Gauss constant(B)Acceleration constant

(C)Deceleration constant(D)Blocking factor

17. Match list-1 (Bus types) with list-2 (Pairs of variables) and select the correct answer using the codes given below the lists:List-I(Bus types)List-II(Pairs of variables)

A. Load Bus1. P & V

B. Generator Bus2. P & Q

C. Slack Bus3. V &

Codes: A B C A B C

(A) 1 2 3(B) 2 3 1

(C) 1 3 2(D) 2 1 3

18. In load flow studies of a power system, the voltage control bus is specified by(A)Real and reactive power(B)Real power and voltage magnitude

(C)Voltage and voltage phase angle(D)Reactive power & voltage magnitude

19. The power angle characteristics of machine-infinite bus system is

It is operating at =30. Which one of the following is the synchronizing coefficient at the operating point?(A)1.0(B)

(C)2.0(D)

20. Possible faults that may occur on a transmission line are1.3-phase fault2.Double line to ground fault

3.Double line fault4.Line to ground fault

(A)1-2-3-4(B)1-4-3-2

(C)1-3-2-4(D)1-3-4-2

21. Consider the following statements:i) It is easier to construct the YBUS matrix as compared to ZBUS.ii) ZBUS is a full matrix while YBUS is sparse.iii) YBUS can be easily modified whenever the network changes as compared to the ZBUS.Which of these statements are correct?(A)1 and 2(B)2 and 3

(C)1 and 3(D)1, 2 and 3

22. The bus impedance matrix of a 4-bus power system is given by

A branch having an impedance of j0.2 is connected between bus 2 and the reference. Then the values of Z22, new and Z23,new of the bus impedance matrix of the modified network are respectively(A)j0.5408 and j0.4586(B)j0.1260 and j0.0956

(C)j0.5408 and j0.0956(D)j0.1260 and j0.1630

23. The network shown in the given figure has impedances in pu as indicated. The diagonal element Y22 of the bus admittance matrix YBUS of the network ise(A)-j19.8(B)j20.0

(C)+j0.2(D)-j19.95

24. The Gauss Siedel load flow method has following disadvantages. Tick the incorrect statement.(A)Unreliable convergence(B)Slow convergence

(C)Choice of slack bus affects convergence(D)A good initial guess for voltages is essential for convergence

25. For a power system the admittance and impedance matrices for the fault studies are as follows.

The pre-fault voltages are 1.0pu at all the buses. The system was unloaded prior to the fault. A solid 3-phase fault takes place at bus 2.The post fault voltages at buses 1 & 3 in pu are(A)0.24, 0.63(B)0.31, 0.76

(C)0.33, 0.67(D)0.67, 0.33

26. For a power system the admittance and impedance matrices for the fault studies are as follows.

The pre-fault voltages are 1.0pu at all the buses. The system was unloaded prior to the fault. A solid 3-phase fault takes place at bus 2.The per unit faults feed from generators connected to buses 1 and 2 respectively are(A)1.20, 2.51(B)1.55, 2.61

(C)1.66, 2.50(D)5.00, 2.50

27. Consider the two power systems shown in figure A below, which are operating in steady state at the same frequency. Separate load flow solutions are computed individually for the two systems, corresponding to this scenario. The bus voltage phasors so obtained are indicated on figure AThese two isolated systems are now interconnected by a short transmission line shown in figure B, and it is found that P1=P2=Q1=Q2=0

(A)10(B)25

(C)-30(D)30

28. For the Ybus matrix of a 4-bus system given in p.u., the buses having shunt elements are

(A)3 and 4(B)2 and 3

(C)1 and 2(D)1, 2 and 4

29. Consider two buses connected by an impedance of (0+j5). The bus 1 voltage is 10030, and bus 2 is 1000V. the real and reactive power supplied by bus 1, respectively are(A)1000W, 268VAR(B)-1000W, -134VAR

(C)276.9W, -56.7VAR(D)-276.9W, 56.7VAR

30. A three bus network is shown in the figure below indicating the p.u. impedance of each element.

The bus admittance matrix, Ybus, of the network is(A)(B)

(C)(D)

31. The bus admittance matrix of a three-bus three line system is

If each transmission line between the two buses is represented by an equivalent -network, the magnitude of the shunt susceptance of the line connecting bus 1 and 2 is(A)4(B)2

(C)1(D)0

32. A single phase load is supplied by a single pase voltage source. If the current flowing from load to the source is 10-150A and if the voltage at the load terminals is 10060V, then the(A)Loads absorbs real power and delivers reactive power(B)Loads absorbs real power and absorbs reactive power

(C)Loads delivers real power and delivers reactive power(D)Loads delivers real power and absorbs reactive power

33. For aa power system network with n nodes, Z33 of its bus impedance matrix is j0.5pu. the voltage at node 3 is 1.3-10pu. If a capacitor having reactance of j3.5pu is now added to the network between node 3 and the reference node, the current drawn by the capacitor pu is(A)0.325-100(B)0.325800

(C)0.371-100(D)0.43380

34. In the following network, the voltage magnitudes at all buses are equal to 1 pu, the voltage phase angles are very small, and the line resistances are negligible. All the line reactances are equal to j1.

The voltage phase angles in rad at buses 2 and 3 are(A)2= -0.1, 3= -0.2(B)2= 0, 3= -0.1

(C)2= 0.1, 3= 0.1(D)2= 0.1, 3= 0.2

35. In the following network, the voltage magnitudes at all buses are equal to 1 pu, the voltage phase angles are very small, and the line resistances are negligible. All the line reactances are equal to j1.

If the base impedance and the line to line base voltage are 100 and 100kV, respectively, then the real power in MW delivered by the generator connected at the slack bus is(A)-10(B)0

(C)10(D)20

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Cmps Paper Objective Paper