SWITCHABLE LONGITUDINAL VOLTAGE SOURCE, DC TRANSMISSION SYSTEM WITH LONGITUDINAL VOLTAGE SOURCE, AND METHOD FOR OPERATING A LONGITUDINAL VOLTAGE SOURCE

摘要

The invention relates, amongst other things, to a switchable longitudinal voltage source (20) having a feed connection (A) for feeding a current, a first output connection (B), and a second output connection (C). The longitudinal voltage source (20) is suitable for switching an electrical voltage of an electrical stored energy source (21) selectively between the feed connection (A) and the first output connection (B) or between the feed connection (A) and the second output connection (C). According to the invention: the longitudinal voltage source (20) has a first switch (SI), which is situated electrically between the feed connection (A) and the first output connection (B), electrically connects the feed connection (A) and the first output connection (B) in the switched-on state, and electrically separates the feed connection (A) and the first output connection (B) from one another in the switched-off state; the longitudinal voltage source (20) also has a second switch (S2), which is situated electrically between the feed connection (A) and the second output connection (C), electrically connects the feed connection (A) and the second output connection (C) in the switched-on state, and electrically separates the feed connection (A) and the second output connection (C) from one another in the switched-off state; and the longitudinal voltage source (20) has a third switch (S3), which is situated electrically in series with the stored energy source (21) and forms a series circuit therewith, which is electrically connected between the two output connections (B, C).