A converter for a wind energy installation and a method. The converter includes an inverter which drives a generator via a plurality of phases and an intermediate circuit having an intermediate-circuit voltage between an upper and a lower intermediate-circuit potential. The generator is driven with phase potentials at a variable frequency. A shift value is calculated between an extreme phase potential and one of the intermediate-circuit potentials, a separation value is determined between a middle phase potential and the closest intermediate-circuit potential, and an additional voltage is generated using the separation value as amplitude. The phase potentials are shifted through the shift value and the additional voltage is added to the middle phase potential. Accordingly, the switching elements in the converter do not need to be clocked in every second half-cycle resulting in reduced switching losses and increased current load capacity of the converter.