A method and apparatus are provided for operation of a converter circuit, which includes a converter unit having a multiplicity of controllable power semiconductor switches, and which is connected via a transformer to a three-phase electrical AC voltage power supply system. The method includes controlling the controllable power semiconductor switches by means of a control signal which is formed from a regulating signal. In order to damp oscillations of a power supply system voltage above the fundamental frequency, a filtered power supply system current is formed by filtering a power supply system current using a low-pass filter characteristic. A filtered transformer inductance voltage is formed by filtering a transformer inductance voltage, which is formed from the power supply system current, using a low-pass filter characteristic. A filtered power supply system voltage is formed by filtering a power supply system voltage using a low-pass filter characteristic. The regulating signal is formed by addition of a regulator voltage, the filtered transformer inductance voltage, and the filtered power supply system voltage, where the regulator voltage is formed by regulating the filtered power supply system current at a power supply system current nominal value.