Optimal control applications & methods vol:13 issue:2 pages:121-144
In this paper two modern control techniques, the H-2 and H(infinity) control design methods, are presented. After a brief theoretical explanation they are applied to a practical example: the control of the air flow rate through an axial ventilator. Modern control techniques are model-based. In the first part of the paper it is explained how a model can be obtained both of the process and of the disturbances acting on it. On the basis of the model, several controllers can be designed. The example clearly illustrates some of the trade-offs of modem control design. The H-2 and H(infinity) controllers are also compared with a classical PI controller.