On frequency analysis of variable parameter linear systems

Determination of a generalized transfer function of a variable parameter linear system is described. The criterion has been obtained which permits stability determination within the interval by the poles location of this function. Bifrequency transfer function is introduced and the criterion of absolute stability using its convergence characteristic obtained. The relationship defining the Laplacian image from the process at the output on the basis of the image of the input (action) and bifrequency transfer function is obtained. Also, the differential equation for generalized transfer functions is obtained. Approximate method for determining these functions for a number of cases is given. Applicability of the discussed approach for a number structural schemes is considered.