Identification of Transformer Leakage Inductance Parameters Based on Dynamic Resistance of Windings

Winding deformation during the operation of power transformers leads to changes in winding leakage inductance, and in order to achieve more accurate on-line identification of leakage inductance parameters, a winding dynamic resistance dependent leakage inductance parameter identification method is proposed. Taking the transformer circuit equation as the reference identification model and the recursive least squares method with forgetting factor as the identification algorithm, a finite element simulation model is established to study the influencing factors of leakage inductance identification. The results show that the change in resistance value has a significant effect on the identification of leakage inductance after excluding disturbance factors such as load and power factor. Based on this, it is proposed to introduce the transformer oil temperature to reflect the dynamic resistance value of the windings, which effectively reduces the error and fluctuation of leakage inductance identification due to the change in resistance value. Finally, the effectiveness of the method in on-line identification of transformer winding deformation is verified by simulated deformation experiments of the winding.