Model of emi filter for asymmetrical measurement setup in standard method

In Introduction are introduced main problems of measurement of EMI filter. Reduced equivalent circuitries for EMI filter are shown. Two optimization routines, Quasi-Newton method and Levenberg Marquardt, were introduced for nonlinear least-squares problems. The spurious elements of filter in asymmetrical measurement setup are searched by Quasi-Newton method. Both own and spurious parameters was searched by Levenberg Marquardt method. Results of both approaches are shown.