Power system MCQ #11

Power system MCQ 157 to 160:

157) Under no-load condition, the current in a transmission line is because of

      (a) corona effect

      (b) capacitance effect

      (c) proximity effect

      (d) back flow from earth

158) Power dispatch through a line can be increased by installing

      (a) series capacitors

      (b) shunt capacitors

      (c) series reactor

      (d) shunt reactor

159) Capacitors are used in power system to

      (a) improve voltage regulation

      (b) improve supply power factor

      (c) change the load characteristic

      (d) all of the above

160) Multi-core cable generally used for

      (a) oval shaped conductor

      (b) square conductor

      (c) sector shape conductor

      (d) oval shape or sector shape conductor

ANSWER: | 157-b | 158-a | 159-d | 160-d |

Power system MCQ 161 to 164:

161) sheaths are used in cable to

      (a) provides proper insulation

      (b) prevent ingress of moisture

      (c) provide mechanical strength

      (d) none of the above

162) A synchronous condenser is a

      (a) synchronous generator

      (b) synchronous motor

      (c) induction generator

      (d) induction motor

163) In a distribution system, which of the following item shares the major cost?

      (a) conductor

      (b) earthing system

      (c) insulators

      (d) distribution transformer

164) As compared to AC transmission system, DC transmission system is free from

      (a) capacitance

      (b) phase displacement

      (c) inductance

      (d) all of the above

ANSWER: | 161-b | 162-a | 163-d | 164-d |

Power system MCQ 164 to 168:

165) Which of the following relays has inherent directional characteristic?

      (a) mho

      (b) impedance

      (c) reactance

      (d) none of the above

166) The relay used for phase fault protection of short transmission line is

      (a) mho

      (b) impedance

      (c) reactance

      (d) IDMT

167) mho relay is used for the protection of

      (a) short line

      (b) long line

      (c) medium line

      (d) any line

168) Differential relays are used for protection of equipment against

      (a) reverse current

      (b) overcurrent

      (c) internal fault

      (d) reverse power

ANSWER: | 165-a | 166-c | 167-b | 168-c |