Semidefinite Programming Techniques for Reduced Order Systems with Guaranteed Stability Margins

In this paper, the compensator based reduced order control design framework of 2] is modiied to yield low order systems with guaranteed stability margins. This result is achieved through use of a logarithmic barrier function. In addition, a reduced basis method is formulated in which the compensator equations are approximated on uneven grids; guaranteed stability margins are also included. The methods are tested numerically on a one dimensional, nonlinear, damped, hyperbolic structural control problem. Examples are provided to illustrate diierences between systems designed by both reduced basis methods.