METHOD AND DEVICE FOR CALCULATING WINDING CURRENTS AT DELTA SIDE FOR A TRANSFORMER

The invention relates to a method and device for calculating winding currents at delta side for a transformer. The transformer has two or more windings, with a first winding being a delta connected winding. The method comprises obtaining line currents measured with measurement equipment associated with lines connected with the windings. The method further comprises calculating zero sequence currents for at least a second winding, from the line currents of a corresponding line. The method further comprises calculating zero sequence currents for the first winding, based on the zero sequence currents for at least the second winding, a phase displacement between the windings, and a turns ratio associated with the windings. The winding currents are calculated from the zero sequence currents of the first winding, and the line currents of a corresponding line. The winding currents values are rendered for one or more operations associated with the transformer.