Q.296 Fast excitation system of the generator will…
A. improve the voltage control
B. improve the power factor
C. improve the reactive power control
D. improve the dynamic stability
Ans.: D
Q.297 The z matrix of 2 port network is given by [0.9 0.2; 0.2 0.6] The element of Y22 of the corresponding Y matrix of the same network is given by
A. 12
B. -0.4
c. 1.8
D. 0.4
Ans.: C
Q.298 The Y bus matrix is a spare matrix because
A. bus incident matrix is a spare matrix
B. Y primitive is a sparse matrix
C. lines are connected to less no. of buses
D. no of lines are less
Ans.: C
Q.299 In a power system network, At which bus the shunt is connected that can be known from
A. reactive power demand
B. type of bus
C. Y bus of the system
D. none of the this
Ans.: C
Q.300 Steady state Stability of a power system is improved by
A. reducing fault clearing time
B. using double circuit lines instead of single circuit line
C. by fast switching
D. decreasing generator inertia
Ans.: B
Q.301 In a thermal power plant, heat from the flue gases is recovered in
A. Economizer
B. Electric precipitator
C. Condenser
D. chimney
Ans.: A
Q.302 The line current in a three phase unbalanced load are Ir = 4+j6, Ib = 2-j2 and Ic = -3+j2, then zero sequence component of current will be
A. 3+j6
B. 9+j10
C. 1+j2
D. 3-j6
Ans.: C
Q.303 The surge impedance loading of the line will be_____ if the length of the line is doubled.
A. doubled
B. four times
C. remains same
D. became half
Ans.: C
Q.304 In case of a balanced three phase sinusoidal AC supply, because of the phase difference
A. neutral wire is not required, if load is balanced
B. rotating magnetic field is produced
C. neutral current is high if load is not balanced
D. all are correct
Ans.: D
Q.25 For formation of the Y bus matrix (using node voltage analysis) in power system network modeling __ is used
A. KVL
B. KCL
C. Faraday’s law
D. all are correct
Ans.: B
Q.306 The rating of given on the name plate of a transformer indicates the:
A. True power which it can supply
B. Apparent power which it draw from the supply mains
C. Apparent power which it can supply
D. True power which it draws from the supply mains
Ans.: C
Q.307 The magnitude of sum of two sinusoidal AC voltages is equal to the magnitude of each individual voltage. What must be the phase difference between voltages?
A. 60
B. 90
C. 120
D. 180
Ans.: C
Q.308 Power factor correcting elements is generally connected in…
A. series with load
B. parallel to the load
C. series with source
D. parallel to source
Ans.: B
Q.309 The PU impedance of a 1089 MVA, 33 KV generator is 1, the ohmic value of its impedance is
A. 1
B. 10
C. 0.5
D. 100
Ans.: A
Q.310 Select the wrong statement from the following in relation to power flow analysis
A. Y bus is required for power flow analysis
B. Approximation is used in FDLF method
C. jacobian is always required
D. No of iteration in N-R method cannot be more than 30 for any system
Ans.: C