Drive system having DC power supply for a submarine

A drive system for a submarine comprising:

• a DC power supply system configured to supply electrical energy to a drive of the submarine;
• a plurality of battery strings, wherein each battery string includes a plurality of series-connected battery modules;
• and
• a plurality of string connection units, each of the plurality of string connection units comprising a bidirectional voltage converter and a switching device either connected in series to the bidirectional voltage converter or incorporated into the bidirectional voltage converter for galvanic isolation of each battery string from the DC power supply system, individual ones of the plurality of string connection units connected to a corresponding one of the plurality of battery strings via which each battery string is selectively connected to or disconnected from the DC power supply system, with each of the plurality of string connection units being configured to adjust a string current flowing in each corresponding battery string.