Study on Electric Field Distribution of Dampness Defect in Oil-paper Capacitive

The electric field simulation calculation of transformer bushing is a key technique for analyzing the insulation performance of bushing. In order to fully understand the electric field distribution of transformer bushing, this paper establishes a finite element model of 126kV transformer oil-paper capacitive bushing based on COMSOL simulation software, and checks and analyzes the electric field distribution of oil-paper capacitive bushing based on this model. The simulation model of moisture defects of the main insulation of the bushing was established, and the internal electric field distribution under the conditions of dry, uniform wet and non-uniform wet was comparatively studied. The calculation results show that the electric field distribution of the main insulation of the bushing is uniform under normal drying conditions, and when the main insulation of the bushing has moisture defects, the radial field strength at the zero screen increases, and with the increase of moisture content, the radial field strength at this place continues to increase, which has an impact on the insulation performance of the bushing. Therefore, in the actual working conditions, attention should be paid to keeping the bushing environment dry, paying attention to ensuring the tightness of the outer insulation of the bushing to prevent water ingress and moisture.