Analytic calculation of leakage inductances of dual frequency concentric windings transformers

Static power electronic converters supplying railways DC or AC motors, require series inductances which can simply be the leakage short-circuit inductances of the traction transformer. This paper describes a one-dimensional analytical method which permits to calculate leakage inductances between primary and secondary windings of dual frequency transformers. A comparison to a two-dimensional analytical method as well as to measurement results on existing units is made. Furthermore, illustration software developed in Visual Basic on Microsoft Excel is presented.