Calculating Dryformer leakage reactance using analytical and finite element methods

Dryformer is an oil-free power transformer that its windings are made of high voltage cross-linked polyethylene (XLPE) cables. Leakage reactance calculation is a key step in transformer design process. Special structure of Dryformer makes conventional analytical methods useless for leakage reactance calculation in this type of transformer. In this paper, an analytical method is proposed for calculating leakage reactance of Dryformer based on its winding structure. The validity of proposed model is verified by means of 3D and 2D finite element models.