High-voltage direct current (HVDC), or transfer, for direct current, direct voltage, typical system, the transfer of electrical energy. This method is a way trail to the transfer of electric energy on the scale of huge, and it is in this context, a good alternative against the traditional method (using alternating current). Manufacturing technology, this type of system to the 1930s in Sweden, Oct. From the first lines made with this technology can be a transmission line between Moscow and kashira, in the Soviet Union in 1951 and transmission system 10 to 20 MW, located in Sweden named that in 1954, came into operation. The transmission line HVDC is now a transmission line Inga- with transfer of 600 MW and with a length of about 1700 km in the Congo located. This transmission line dam Inga to mine copper connects.