THREE-PHASE THREE-LEG TRANSFORMER MODEL FOR CALCULATION OF ASYMMETRIC MODES IN ELECTRICAL NETWORKS

The model of a three-phase three-legged transformer in the form of a nodal admittance matrix, based on short circuit parameters for symmetric systems components is presented. The model permits to take into account the main features of such transformers in asymmetric modes, connected with electromagnetic coupling of different phases. Results of considering the example of asymmetric modes of three-legged transformer with widely used diagram of winding connection showed, that the data indicated in literature concerning features of its behavior in asymmetric modes can be specified and completed on the basis of developed model.