Previous Year Question
Which conductor characteristic is most effective in reducing the corona effect in EHVAC transmission lines?
Correct answer: D
Explanation
Increasing conductor diameter/surface area reduces the electric field intensity at the conductor surface. A lower surface gradient raises the disruptive-corona threshold and therefore reduces corona formation and loss.
Step-by-step solution
Correct Answer
D — Large surface area
Explanation
Increasing conductor diameter/surface area reduces the electric field intensity at the conductor surface. A lower surface gradient raises the disruptive-corona threshold and therefore reduces corona formation and loss.
Key Concept
Effect of Conductor Size on Corona
Exam Point
Larger conductor radius → lower surface electric stress → less corona.
Exam tip
Larger conductor radius → lower surface electric stress → less corona.
Quick method
Larger conductor radius → lower surface electric stress → less corona.