Optimization Arrangement of angle rings in Converter Transformer Valve Winding End Insulation Structure

Angle ring which be placed in the big gap between the winding end and the yoke, could improve the electric field distribution and the insulation reliability of the transformer. Therefore, the optimal arrangement of the angle ring is an important part of the main insulation structure design. In this paper, multi-objective optimization algorithm, particle swarm optimization algorithm and finite element sub-model calculation technology were used to optimize the inside and outside angle rings arrangement of the valve winding end insulation structure, with maintaining the original number, the thickness of the angle rings and arc radius unchanged. During the optimization process, the minimum insulation margin along the electric fluxlines in each assessment oil clearance was selected as the objective function of optimization. The purpose was to make insulation margin along the direction of the electric fluxlines as close as possible among the oil gap. After optimization, it not only made the minimum insulation margin floating range of each assessment clearance smaller, but also increased the minimum insulation margin of the entire end insulation. After optimization, the minimum margin of the outside oil gap increased from 1.35 to 1.54, and the minimum margin of the inside oil gap increased from 1.4 to 1.57.