AN APPARATUS FOR CONTROLLING THE ELECTRIC POWER TRANSMISSION IN A HVDC POWER TRANSMISSION SYSTEM

摘要

An apparatus (202; 212; 908) for controlling the electric power transmission in a high voltage direct current, HVDC, power transmission system comprising at least one HVDC transmission or distribution line (102, 104, 106, 108, 110, 112, 114) for carrying direct current, DC, the apparatus being arranged to control the direct current of the HVDC transmission or distribution line by introducing a DC voltage in series with the HVDC transmission or distribution line, wherein the apparatus comprises a plurality of electric power source sections (204; 910) connectable to an electric power source (316), and a plurality of DC-to-DC converter units (302; 602; 902). Each DC-to-DC converter unit of the plurality of DC-to-DC converter units comprises a first DC side (206) for output and/or input of direct current and a second DC side (208) for output and/or input of direct current. Each DC-to-DC converter unit of the plurality of DC-to-DC converter units is connectable via its first DC side to the HVDC transmission or distribution line, and each DC-to-DC converter unit of the plurality of DC-to-DC converter units is connected via its second DC side to at least one of the plurality of electric power source sections. A HVDC power transmission system comprising at least one apparatus (202; 212; 908) of the above-mentioned sort.