Professional Answer: The main difference lies in the type of current used:

• Alternating Current (AC) Transmission: This is the most common method for power transmission. Its key advantage is the ease with which voltage can be changed using transformers, allowing it to be stepped up for efficient long-distance transmission and then stepped down for safe local distribution.

• Direct Current (DC) Transmission: While less common, High-Voltage Direct Current (HVDC) is used for specific applications, such as very long-distance transmission (especially submarine cables) and connecting asynchronous power grids. DC does not experience certain losses (like skin effect and corona discharge) that are present in AC systems, making it more efficient for these particular use cases.

Our company, Ningbo Changshi Electric Power Machinery Manufacturing Limited, provides the essential tools and equipment for both AC and DC overhead and underground projects, offering comprehensive solutions for any power line construction and maintenance need.