MCQ in Power Plant Engineering Part 3 | REE Board Exam

This is the Multiple Choice Questions Part 3 of the Series in Power Plant Engineering as one of the Electrical Engineering topic. In Preparation for the REE Board Exam make sure to expose yourself and familiarize in each and every questions compiled here taken from various sources including but not limited to past Board Exam Questions in Electrical Engineering field, Electrical Engineering Books, Journals and other Electrical Engineering References.

Continue Practice Exam Test Questions Part 3 of the Series

⇐ MCQ in Power Plant Engineering Part 2 | REE Board Exam

Choose the letter of the best answer in each questions.

101. Running cost of a hydro plant with respect to that of a thermal plant is

a. More

b.  Less

c.  Varying from installation to installation

d. equal

102. Pick up the odd plant from the following

a. Steam

b. Hydro

c. Tidal

d. Nuclear

103. Pick up the odd plant from the following:

a.  Steam

b. Wind turbine generator plant

c. Tidal

d. Solar

104. The role of the economiser is to pre-heat

a.  Pulverised coal

b. Boiler feed water

c. Air used for combustion

d. provide clean air

105. Superheater & reheater are used to

a.  improve the condition of steam

b.  heat air used for combustion

c.  heat boiler feed water

d.  decrease efluent

106. Governor is used with the steam turbine to regulate

a.  Steam temperature

b. Steam pressure

c. Power output

d. Speed

107. Cooling of 500 MW turbo-generators is usually done by the following coolants

a.  Nitrogen & hydrogen

b.  Hydrogen & water

c.  Carbon dioxide & hydrogen

d. Water only

108. The specific speed of a hydro turbine depends on

a. Actual speed

b.  Head of operation

c.  Output power

d.  Actual speed ,head of operation & output power

109. The most common type of hydro turbine with a moderate value of the specific speed is

a. Pelton

b. Francis

c. Kaplan

d. wind

110. Pumped storage hydroelectric plant can be operated with

a.  Upstream reservoir only

b.  downstream reservoir only

c.  a and b

d.  none of these

111. Hydro-generators are usually

a.  Round rotor machines

b.  Salient pole machines

c.  Homopolar machines

d. Bipolar machine

112. Heavy water in a nuclear reactor is used for

a.  Cooling & moderation

b.  Cooling and shielding radiation

c.  Moderation & shielding radiation

d.  Moderation only

113. The size and weight per unit power of a fast breeder reactor in comparison to a reactor of any of the thermal types is

a.  Much less

b.  Much more

c.  more or less the same

d.  always zero

114. Compared to turbines in the conventional coal-fired thermal stations, nuclear power plant turbines use steam at

a.  higher pressure & temperature

b.  lower pressure & temperature

c.  higher temperature & lower pressure

d. higher power factor

115. Gas turbine temperature corresponds to

a.  Boiling water temperature of 100°C

b.  Superheated steam temperature of 550°C

c.  Around 1000°C

d.  Around 66000°C

116. Gas turbine works on

a. Rankine cycle

b.  Brayton cycle

c. Carnot cycle

d. Roel cycle

117. The HVDC converter

a.  Does not consume reactive power

b.  Consumes as much reactive power as real power

c.  Consumes 50% of the real power

d.  Is not economical

118. A back to back HVDC link can be advantageous compared to AC primarily because

a.  It is cheaper

b.  Of stability considerations

c.  Of controlled power glow

d.  It is costly

119. A 12-pulse bridge is preferred in HVDC because

a.  It eliminates certain harmonics

b.  It results in better power factor

c.  Series connection of converters on D.C. side is better

d.  cheaper

120. Fault on a two terminal DC link is removed by

a.  Breakers on DC side

b.  Breakers on AC side

c.  Current control of converters

d. Current chopping

121. From the economic point of view , a power system should have a load factor

a.  About 0.12

b.  About 0.5

c.  About1

d. zero

122. From the economic point of view , a power system should have a diversity factor

a.  Much less than 1

b.  Nearly equal to but less than one

c. Always constant

d.  Greater than one

123. Peak load hydro power plants compared to base load thermal plants have plant capacity factor

a. Much lower

b.  Much higher

c.  Almost equal

d.  Always constant

124. Run-of-river plants are used for

a.  Base load operation

b.  Peak load operation

c.  Near base load

d.  Regulating plant

125. The two-part tariff is based on

a.  MW and MVar

b.  MW and MVA

c.  MWH and MVA

d. MVArH

126. SF6 gas has excellent heat transfer properties because of its:

a.  Higher molecular weight.

b.  High gaseous viscosity.

c. Low density

d. Low cost

127. In order to have lower cost of electrical energy generation:

a.  The load factor and diversity factor should be low.

b.  The load factor should be low but diversity factor should be high.

c.  The load factor should be high but diversity factor low.

d.  The load factor and diversity factor should be high.

128. For stability and economic reasons we operate the transmission line with power angle in the range:

a.  10 deg. to 25 deg.

b.  30 deg. to 45 deg.

c.  60 deg to 75 deg.

d.  65 deg. to 80 deg.

129. For an existing a. c. transmission line the string efficiency is 80%. Now if d.c. voltage is supplied for the same set up, the string efficiency will be:

a. 80%.

b.  More than 80%.

c.  Less than 80%.

d. 100%.

130. Effect of increase in temperature in overhead transmission lines is to:

a.  Increase the strength and length.

b.  Decrease the strength and length.

c.  Decrease the stress but increase the length.

d.  None of these.

131. For economic operation, the generator with highest positive incremental transmission loss will operate at:

a.  The lowest positive incremental cost of production.

b.  The lowest negative incremental cost of production.

c.  The highest positive incremental cost of production.

d.  None of these.

132. An alternator is delivering the load current; its percent regulation is found to be zero. The type of load it delivers is:

a. Capacitive.

b. Inductive.

c. Resistive.

d. admittance

133. The incremental transmission loss of a plant is:

a. Positive always.

b. Negative always.

c.  Can be positive or negative.

d. zero

134. Load flow study is carried out for:

a. Fault calculations.

b. Stability studies.

c. System planning.

d.  Load frequency control.

135. If the penalty factor of a plant is unity, its incremental transmission loss is:

a. 1.0.

b. –1.0.

c. Zero.

d. 10.0

136. If the load of an isolated generator is increased without increasing the power input to the prime mover:

a.  The generator will slow down.

b.  The generator will speed up.

c.  The generator voltage will increase.

d.  The generator field current will increase.

137. When alternative sources of energy are available to a power system, they should be used in such a way that:

a.  Thermal generation is held at a minimum.

b.  The most efficient plants are always loaded to their maximum.

c.  Overall production cost is minimized.

d.  Near at the load point

138. In a thermal-electric generating plant, overall efficiency is improved when:

a.  Boiler pressure is increase.

b.  The difference between initial pressure and temperature and exhaust pressure and temperature are held at a maximum.

c.  Load on the units is increased.

d.  It is always loaded

139. When load on a thermal unit is increased, fuel input

a.  Increase.

b.  Does not change.

c. Decrease.

d.  It is constant

140. Incremental-heat-rate curves, for thermal generating units, are used to determine the

a.  Fuel cost in P per hour.

b.  Values to which the units should be loaded to result in minimum fuel cost.

c.  Cost per unit of electrical output.

d. Ramp rate

141. When generating units are loaded to equal incremental cost:

a.  Minimum fuel cost result.

b.  Fuel cost is at a maximum.

c.  Fuel cost is not affected.

d.  Losses are minimized

142. One advantage of computer control of generating units is that:

a.  Var output of the unit is minimized.

b.  All units under the control of the computer will be loaded to the same load.

c.  Loading of the units will be frequently adjusted to maintain them at equal

d.  Incremental fuel costs.

143. If the fuel cost of one unit, operating in parallel with other units, is increased and it is desired to maintain fuel cost, the load on the unit will be

a. Increase.

b. Held constant.

c. Decrease.

d. None of these

144. In a power system using both hydro and thermal generation, the proportion of hydro generation can be increased by

a.  Increasing the prize (gamma) of the water.

b.  Reducing the prize of the water.

c.  Increasing the field currents of the hydro generators.

d.  Used water with high specific gravity

145. In economic operation of a power system, the effect of increased penalty factor between a generating plant and system load center is to

a.  Decrease load on the generating plant.

b.  Increase load on the plant.

c.  Hold the plant load constant.

d. None of these

146. Governors for controlling the speed of electric generating units normally provide

a.  A flat speed load characteristic.

b.  An increase of speed with increasing load.

c.  A decrease of speed with increasing load.

d. None of these

147. On load –frequency-control installation, error signals are developed proportional to the frequency error. If frequency decline,the error signal will act to

a.  Increase prime mover input to the generators.

b.  Reduce prime mover input to the generators.

c.  Increase generator voltages.

d. None of these

148. When to or more system operate on an interconnected basis, each system

a.  Can depend on the other systems for its reserve requirements.

b.  Should provide for its own reserve capacity requirement.

c.  Should operate in a “flat frequency” mode.

d. None of these

149. When interconnected power system operate with tie-line bias, they will respond to

a.  Frequency changes only.

b.  Both frequency and tie-line load changes.

c.  Tie-line load changes only.

d. None of these

150.  A metering installation for a 115-kV tie point between two power system has 10000:5 current transformers in each phase and 600:1 potential transformers connected line to ground. Assuming unity power factor, the multiplying factor that should be used to determine the power in the circuit in kilowatts is

a. 360

b. 3600

c. 207.8

d. None of these

⇒ MCQ in Power Plant Engineering Part 4 | REE Board Exam