Charge transport multiscale modelling for bridging material properties to insulation performance: case study of moisture deterioration at cellulose–oil interface

Electrical insulation materials inevitably undergo gradual deterioration under complex operational stresses, which may ultimately lead to equipment malfunction and even power failures. However, a persistent gap remains between measured macroscopic properties and actual insulation performance, hindering the effective translation of test results into engineering practice. A representative example is moisture-induced deterioration in cellulose–oil insulation, where the moisture distribution and its microscopic influence on charge transport (CT) remain largely speculative.