2nТ-SHAPED EQUIVALENT CIRCUIT OF A TRANSFORMER COMPRISING n WINDINGS
The new detailed 2nT-shaped equivalent circuits of a transformer containing n concentric windings, displaying on schematic all magnetic flux between the windings, in the windings, in the elements of the magnetic circuit and between it and the tank in case of saturation of the magnetic circuit is presented. It is based on the idea of stitching the 4T-shaped circuit models for two-winding transformers, considered as a unit cell of a more complex 2nT-shaped structure. The accuracy of the occurrence in various parts of the magnetic circuit with short-circuit one or more windings of the magnetic super- and counter-fluxes in comparison with the fluxes of idling is confirmed. It is shown that the observation of such anomalous fluxes in the equivalent circuit is possible due to the presence of negative inductances. It is proved that the multi-winding transformer equivalent circuits without negative elements are characterized by a three-diagonal matrix of inductances.