High frequency model and transient response of transformer windings

The high frequency model of transformer winding is indispensable in analyzing the transients particularly caused by the very fast transients which occur at the time of disconnecting switch operations. The transients in transformer have been analyzed using a circuit of interlinked inductances and capacitances whose values have to be properly determined. The circuit constants have been hitherto calculated in a model taking each coil section pair as a building block. The present paper proposes the method that enables further subdividing the unit. The circuit transients are computed utilizing the FFT technique. The voltage oscillations of the winding subjected to an impulse voltage are calculated. The correspondence with the experimental results is satisfactory. The response to a chopped impulse shows this method´s applicability to high frequency analyses. Since the constants are calculated directly from the design parameters of transformer winding, this technique is particularly useful in developing and designing transformers.