Corona in transmission lines is affected by:
- Spacing of conductors
- Atmospheric conditions
- Voltage level
- Size of conductors
- All of these
Correct answer: 5. All of these
Explanation: Corona in transmission lines depends on all of the above mentioned factors:
- Spacing between conductors: The larger distance between conductors reduces the electrostatic stress at conductors surface
- Atmospheric conditions: Corona occurs due to the ionization of air around conductors. In stormy weather more number of ions are present than normal and thus corona formation happens at much low voltage levels in stormy weather as compare to fair weather conditions
- Voltage level: The higher the voltage is the lower is the chance of corona and vice versa
- Size of conductor: Size of the conductor also plays an important role in corona formation