Plant for transmitting electric power, including VSC-converter and DC/DC-converter

摘要

PCT No. PCT/SE98/00502 Sec. 371 Date Sep. 20, 1999 Sec. 102(e) Date Sep. 20, 1999 PCT Filed Mar. 20, 1998 PCT Pub. No. WO98/43336 PCT Pub. Date Oct. 1, 1998A plant for transmitting electric power comprises at least one VSC-converter (1). It comprises also at least one DC/DC-converter (33, 34) having two current valves connected in series and an inductance connected to a midpoint therebetween. The DC/DC-converter is through said inductance connected to a first of the poles of the direct voltage side of the converter and through a first output terminal connected to one of the current valves to the second of the poles so as to obtain an unbalanced step-up-transformation of the direct voltage between the two poles while obtaining a potential having a higher value on the second output terminal (27) of the DC/DC-converter connected to the second current valve than on said first output terminal (28).