This set of Power Systems Questions and Answers for Experienced people focuses on “Skin Effect and Proximity Effect – 2”.
1. Which of below factor(s) contribute to the more receptibility to pollution of insulators?
a) Ionic current
b) Uniform voltage
c) Electrostatic voltage
d) Ionic current and Electrostatic voltage
Explanation: The ionic current and the electrostatic voltage that develops contributes towards the receptibility of pollution in insulators.
2. More number of insulators are needed in AC line as compared to DC line
Explanation: No, DC line need more because of thermal runaway, high unit flashover and contamination.
3. The factors which contribute more to the addition of insulator in HDVC line are ____________
a) high unit flashover
c) thermal runaway
d) high unit flashover, contamination and thermal runaway
Explanation: All the factors add to the insulator addition.
4. What makes porcelein type insulator to be off market?
b) Greater failure rate
c) Self clearing
d) Weight and greater failure rate
Explanation: They have higher probability of fault occurrence and possess larger weight.
5. Most industrially accepted insulators used in HVDC is/are ___________
a) high resistance toughened glass type
b) porcelein type
c) silicon rubber composite type
d) all of the mentioned
Explanation: HRTG is mostly accepted.
6. What is the major problem in current interruption in DC circuit?
a) No natural zero current
b) Extra energy stored in circuit
c) High flashover
d) All of the mentioned
Explanation: There is no natural zero current in DC circuit which poses problem.
7. A two conductor DC line is more reliable than a three conductor AC line.
Explanation: A two conductor DC can always find path through earth or sea than AC system.
8. Stunt capacitors are installed on ____ and smoothing reactor is installed in ____ in TL.
a) AC side, DC side
b) DC side, DC side
c) AC side, AC side
d) DC side, AC side
Explanation: Shunt capacitors are connected at dc side while inductor at ac.
9. There is no requirement of reactive power at the converter station of a HVDC link.
Explanation: There is requirement of reactive power due to phase shift between fundamental as current and voltage and commutation process.
10. _______ polarity is preferred on OH lines due to less radio interference.
d) Any of the mentioned
Explanation: Negative polarity is preferred on overhead lines.
Sanfoundry Global Education & Learning Series – Power Systems.
To practice all areas of Power Systems for Experienced people, here is complete set of 1000+ Multiple Choice Questions and Answers.