A transfer function identification method of the electrical servo system based on isolation characteristic points

A new idea of identification method based on isolation characteristic points is proposed to solve the transfer function identification problem such as the practical electrical servo system which contains some nonlinear items. The characteristic points are chosen from the system frequency characteristic curve, and can be adjusted alone by complex adjusting coefficients of the preliminary transfer function. It makes the fitting curve close to the test curve quickly by going on iterative, which improves the identification´s precision.