Application of the Popov criterion to design of nonlinear systems

A method for nonlinear system design based on the generalized Popov stability criterion is developed. It is shown that although the design method is applicable for all values of
q
in the Popov theory, it is particularly useful when
q
is nonzero since it greatly simplifies the design effort for this case. All designs are accomplished in conjunction with the Nyquist and modified Nyquist loci. Basic to the design procedure is the development and utilization of the modified frequency-response polar loci for lag and lead compensation networks. An example is included to illustrate the procedure described.