Robust Switched System Controller Design in the Frequency Domain

A new frequency domain switched controller design procedure is proposed applicable for both SISO and MIMO multi-model systems represented in an affine form. Robust theoretic approach based on the Small Gain Theorem is used to develop a frequency domain condition for closed-loop stability of the multi-model plant in all operation modes as well as stability during switching between individual controllers. Using this condition, a robust switched controller design procedure based the Equivalent Subsystems Method is developed to guarantee robust stability in individual operation modes in addition. The developed design procedure is demonstrated on a case study. The designed robust switched controller has been successfully verified by experiments on a TITO laboratory plant.