Which portion of the transmission system experiences faults most frequently?

Overhead lines experience faults most frequently due to their exposure to environmental conditions. These lines are often installed at significant heights and are subject to various natural elements such as wind, ice, and lightning. The wear and tear from weather conditions can lead to physical damage or conductor sagging, which increases the likelihood of faults. Additionally, overhead lines are vulnerable to tree falls, animal interactions, and other external factors that can directly cause faults.

Other components like transformers, alternators, and underground cables typically have more protection from environmental hazards. Transformers and alternators are often housed in controlled environments, and underground cables, while susceptible to certain types of damage, benefit from being shielded from many weather-related issues. As a result, overhead lines stand out as the most fault-prone segment of the transmission system.