The present invention is concerned with a reduction of a DC offset in a power electronic converter output current to prevent saturation of a transformer connected to the converter. A current measurement DC offset of a low-cost current transducer is compensated online by using a DC voltage transducer signal indicative of a DC component in the converter current. This DC component is compared to the DC current measured with the low-cost current transducer and any difference is used for the compensating, or calibrating, the DC offset of the low-cost current transducer to prevent saturation of the coupling transformer. The combination of two low-cost transducers in order to replace one high-cost component avoids control stability problems and saves both on material and on commissioning cost.