Some embodiments may include a multi-stage converter comprising: a branch connected between a positive busbar and a negative busbar; and a control device. The branch has two arms connected in series. The arms each comprise a series circuit including a plurality of two-pole submodules, an energy store, and a communication connection to the control device. The communication connection transmits state of charge of the energy store and a switching instruction for the respective submodule. For at least a subset of the submodules, the communication connection comprises a common communication connection with a plurality of insulation paths having an insulation capability in each case of at most 5 kV.