Assessing the Service Life of Turbogenerator Stator Winding High-Voltage Insulation
DOI:
https://doi.org/10.24160/0013-5380-2026-6-26-34Keywords:
insulation system, service life assessment, aging, stator winding, turbine generatorAbstract
The aim of the study is to develop a theoretical model for assessing the residual life of turbogenerator stator winging high-voltage insulation that would take into account the cascading pattern in which its components degrade. To develop the model, a systematic approach was used, which formalizes the state of the heterogeneous structure (ground insulation, corona protection, and side packing) using vector state functions and mutual influence matrices. The insulating materials degradation kinetics under the conditions of combined electrical, thermal, and vibration loads, as well as in simulating discharge activity is studied. The developed model can be applied to predict the insulation technical condition at various stages of the equipment life cycle. The most significant results are the hierarchical organization of insulation elements using vector state functions and mutual influence matrices, the incorporation into the model of the theory of degradation mechanism temperature stratification, and the establishment of functional relationships between defect morphology, local electric field strength, and diagnostic parameters (tanδ and partial discharge characteristics). The practical significance of the results lies in the applicability of the development for maintenance scheduling and extension of the turbogenerator design service life based on its actual condition, as well as for optimizing design solutions at the insulation system designing stage.
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