Final answer:
It is true that grease on conductors can result in the generation of corona, as it disrupts the uniformity of the electric field necessary for avoiding such discharges.
Step-by-step explanation:
The statement that grease on conductors can cause the generation of corona is true. Corona discharge is an electrical discharge brought on by the ionization of a fluid such as air surrounding a conductor that is electrically charged. Grease or other contaminants on a high-voltage conductor can create unevenness on the surface, leading to a non-uniform electric field, which enhances the conditions necessary for corona to occur.
- Corona discharge typically forms when the electric field (voltage gradient) around a conductor is high enough to ionize the air (or another fluid) but not high enough to cause a full arc or breakdown.
- Grease or dirt on the surface of high-voltage conductors increases the likelihood of corona because it disturbs the uniformity of the electric field around the conductor.
- Corona can lead to energy losses, produce audible and radio noise, and cause degradation of conductor materials over time.