Patent ID: 8618698

Claim:
A modular multilevel converter system, comprising: a plurality of series connected two-terminal M2LC subsystems arranged into at least two output phase modules, wherein a first one of the output phase modules defines a total value of inductance and comprises: a positive arm; and a negative arm; and a control system module communicably connected to the two-terminal M2LC subsystems of the first one of the output phase modules, wherein the control system module is configured to apply selectively reassigned modulated switch functions to only one of the following at a given instance of time: the two-terminal M2LC subsystems of the positive arm of the first one of the output phase modules; and the two-terminal M2LC subsystems of the negative arm of the first one of the output phase modules, wherein the selective reassigning of the modulated switch functions forces charge balance of the individual capacitors of the series connected two-terminal M2LC subsystems at a predetermined rate.