Method for operating a multi-phase multi-level converter that is connected to an energy supply via a transformer and has a plurality of phase modules that are each formed from a multiplicity of electrically series-connected two-pole submodules that each have a plurality of semiconductor switches (710, 710') and in each case one energy store at which an intermediate circuit voltage (Uzkn) is present, wherein, for each phase module, the phase module current is regulated on the basis of a predefined setpoint current, characterized in that, for each phase module, a) the intermediate circuit voltages (Uzkn) of the submodules are measured, b) the amplitudes of the system-frequency AC component of the intermediate circuit voltages (Uzkn) of the submodules are determined and c) the DC output (Idc) of the phase module is determined on the basis of the amplitudes of the system-frequency AC components and the phase module voltage associated with the phase module, and in that the associated setpoint currents are corrected on the basis of the determined DC outputs (Idc) of the phase modules such that the DC outputs (Idc) for all phase modules are adjusted to the same current level, such that no DC component difference is able to enter the transformer, wherein, for each phase module, a) the phase module current is measured, b) the setpoint current is determined on the basis of a predefined active-power or reactive-power setpoint value, c) the output setpoint current is compared with the measured phase module current, d) an actuating voltage is calculated on the basis of the difference corresponding to the control error and is output, and a pulse pattern voltage is generated for each phase module on the basis of the actuating voltage, and the switching commands for the individual submodules are generated on the basis of the pulse pattern voltage. wherein, for each phase module, the phase module current is regulated on the basis of a predefined setpoint current, characterized in that, for each phase module, a) the intermediate circuit voltages (Uzkn) of the submodules are measured, b) the amplitudes of the system-frequency AC component of the intermediate circuit voltages (Uzkn) of the submodules are determined and c) the DC output (Idc) of the phase module is determined on the basis of the amplitudes of the system-frequency AC components and the phase module voltage associated with the phase module, and a) the intermediate circuit voltages (Uzkn) of the submodules are measured, b) the amplitudes of the system-frequency AC component of the intermediate circuit voltages (Uzkn) of the submodules are determined and c) the DC output (Idc) of the phase module is determined on the basis of the amplitudes of the system-frequency AC components and the phase module voltage associated with the phase module, and in that the associated setpoint currents are corrected on the basis of the determined DC outputs (Idc) of the phase modules such that the DC outputs (Idc) for all phase modules are adjusted to the same current level, such that no DC component difference is able to enter the transformer, wherein, for each phase module, a) the phase module current is measured, b) the setpoint current is determined on the basis of a predefined active-power or reactive-power setpoint value, c) the output setpoint current is compared with the measured phase module current, d) an actuating voltage is calculated on the basis of the difference corresponding to the control error and is output, and a pulse pattern voltage is generated for each phase module on the basis of the actuating voltage, and the switching commands for the individual submodules are generated on the basis of the pulse pattern voltage. a) the phase module current is measured, b) the setpoint current is determined on the basis of a predefined active-power or reactive-power setpoint value, c) the output setpoint current is compared with the measured phase module current, d) an actuating voltage is calculated on the basis of the difference corresponding to the control error and is output, and a pulse pattern voltage is generated for each phase module on the basis of the actuating voltage, and the switching commands for the individual submodules are generated on the basis of the pulse pattern voltage.