The invention relates to a modular multilevel converter (2) having a control module (4) and a computer (10) for computing a setpoint for the internal energy of the converter stored in the capacitors of the submodules of the arms. The control module is configured to deduce, from the setpoint for the internal energy of the converter, a setpoint for the voltage across the terminals of each modeled capacitor, which setpoint is used for regulating the voltage across the points of common coupling between the converter and the DC power supply network and the voltage across the terminals of each modeled capacitor.