Alternating current (AC) and Direct current (DC) are the two types of power transmission. The most common form of energy transmission is AC power, but in some specific applications, DC transmission can be found.
What are the reasons behind using DC transmission, particularly for extra-high voltage and ultra-high voltage transmission?
There are some major reasons why AC power is preferred over DC power lines for transmission:
Power = V x I x PF (P=Power, V=Voltage, I= current and PF=Power factor)
Historically, we have seen the AC power line for transmission rather than DC power. But nowadays, specific conditions for increasing transmission efficiency and reliability will cause us to challenge the use of alternative current (AC) transmission systems.
Intensive work is being carried out on direct current (DC) systems because of the limitations of AC voltage systems such as power losses, unavoidable transfer of reactive power and the increasing power losses due to skin effect or corona. Due to high transmission power values, it isn’t very easy to use long cables (submarines).
We can use the DC transmission for extra-high voltage and ultra-high voltage transmission for the following reasons: