The 19th century battle between Nikolai Tesla’s alternating current (AC) and Thomas Edison’s direct current (DC) technologies had an undisputed winner. The vast majority of the world’s transmission and distribution grids work now on AC. But DC—and high-voltage direct current (HVDC)—is attracting renewed interest.
New Applications Emerge for HVDC
The benefits of HVDC include its ability to transmit power over long distances without technical limitations and interconnect networks that are asynchronous or that operate at different frequencies. As power grids are adapted to incorporate energy from renewable sources, the flexibility that HVDC connections offer to control power and improve AC system stability are attracting attention. However, HVDC’s integration within an AC system still has to be carefully considered and requires power providers to rethink the role of AC voltage control.
