Resumen:
The great evolution that control systems have had in the last years, has brought the need to make a more precise control, taking into account all possible situations that can be presented. Within these possibilities, the control system's performance-as well as-the robustness must be considered as important attributes that every control-loop has to consider. From the performance side, considering the two possible modes of operation for the system, the requirements have to include good disturbance rejection (regulation-control) and set-point tracking (servo-control), what represents by itself a trade-off between these both considerations. Moreover, if we look from the system's robustness point of view, due the process variations, it is an important aspect that should be included explicitly in the design stage. However, the accomplishment of the corresponding robustness specification is not …
