Integrated Robust H-Infinity Controller Synthesis in Respect of Automotive Engineering Applications

This paper treats the complete robust H_∞ controllers design. The whole synthesis is exemplified by the idle speed control problem at passenger cars and light trucks. Subsequently the robustness of the designed controller is tested and compared to conventional P and PI controllers.

The main steps of controller synthesis are described detailed in this work. First, a closed loop structure has to be chosen. For this purpose, basic principles will be introduced. After this, the weighting matrices for the cost functions have to be defined. Finally, the choice of the calculation algorithm is important. In this approach, the idle speed control is done with the Mixed-Sensitivity design and a derivation of the Doyle-Glover (DGKF) algorithm. The choice for the weighting matrices is depicted clearly in the frequency domain. Finally, a comparison between conventional P(I)- controllers and the introduced H_∞ - method is demonstrated and discussed.