Abstract:
The researches done on calculating leakage inductance of a toroidal transformer were
rare. In this research it is attempted to fill this gap by formulating a method to
calculate leakage inductance of a toroidal transformer.
Finite Element Method analysis is used to calculate the leakage inductance value for
the horizontal plane of the toroidal toroidal transformer and estimate the leakage
inductance of toroidal transformer. Open source magnetic finite element method
software FEMM is used to implement the calculation model. The calculated values
are compared against different winding methods used in toroidal transformer. Output
of the model did show good correlation with normal toroidal transformer winding
method which is being used in almost all the toroidal transformers with few
exceptions of special winding methods. After introducing a correction factor it was
able to achieve maximum error percentage of +/- 20% for the calculated values
compared to the values measured from prototype samples. This is a good
approximation when considering in a production batch of same transformer design,
about +/- 10% variation is observed in measured leakage inductance values due
production variations.
