A three phase core-type transformer iron core model with included magnetic cross saturation

摘要

Three phase transformers used in the electric power applications arc composed either of three single phase transformers or they are three limb core type. The majority of three phase core-type transformer dynamic models neglect magnetic nonlinearity and saturation. In addition, all commercially available electromagnetic transient simulation programs offer only saturated three phase lumped parameters transformer models built of three single phase transformer models. Therefore, the efficient and realistic analysis of some specific but very frequent transient states like unsymmetric loading of three phase core-type transformer is impossible. Some attempts to incorporate magnetic nonlinearity in three phase core-type transformer dynamic model can be found in literature [1] -^s[3].