SUMMARYStructured H ∞ -synthesis subject to time domain performance specifications is introduced. Our method allows to control trajectories of the linearized system and the underlying nonlinear dynamics simultaneously. A non-smooth bundle optimization method for this class of programs is proposed and discussed. Our approach is tested against two benchmark studies: control of a rotational actuator to attenuate vibration noise, and control of a continuous crystallizer. Our algorithm gives a local convergence certificate and is suited for systems with large state dimension.

The LQG/LTR procedure is a classical means to desensibilize a system in closed-loop with respect to disturbances and system uncertainty. We discuss an extension of LTR which can be applied in more general situations. As an example, we show that PID controllers can be robustified with this approach.

H2-control with structured controllers is discussed, and a way to enhance the robustness of the design with respect to real uncertain parameters is proposed.Index Terms-Structured H2 control, parametric robustness.