Loop Gain Margin Research Articles

A graphical approach to computing loop gain margins for TITO systems

An effective method is presented to compute the loop gain margins exactly for two-input–two-output processes. The stable regions in parameter space are first obtained by determining the stability boundaries and the loop gain margins found within the stable regions. Examples are provided for illustration and comparison with other methods.

Exact computation of loop gain margins of multivariable feedback systems

This paper addresses the problem of loop gain margins of multivariable feedback system. A frequency domain approach is proposed to accurately computing loop gain margins for multivariable feedback systems. With the help of vector mapping method, the loop gain margins problem is converted to some constrained optimization, which is solved numerically by the Lagrange multiplier and Newton–Raphson iteration algorithm. The proposed approach can determine all the stabilizing boundaries and provide exact gain margins in comparison with conservativeness of the linear matrix inequalities (LMI) results reported before.