Determination of Moisture Content during Dynamic Loading of Liquid-Filled Distribution Transformers

The current study focuses on the evaluation of the thermal behavior and the corresponding water distribution in the insulation systems of a transformer filled with synthetic ester liquid during steady-state and transient operations. The available literature on lab investigations on moisture content in liquid and solid insulation is applied to a case study transformer. The study involves the application of a dynamic thermal model integrated with a model for moisture content estimation, which considers the dynamic loading process to calculate the temperatures and estimate the moisture content balance between the liquid and solid insulations as a transient condition in different regions of the entire transformer, as discrete elements. The findings suggest the potential for dynamic transformer modeling to enhance both operational performance investigation and onsite assessment of insulation conditions, particularly regarding moisture migration between solid and liquid insulation layers