Youla Parameterization for Feedback Systems

In this chapter, the authors explore how to apply the Youla parameterization method to MIMO systems. Similar to the SISO feedback loop, they discuss the role of neoclassical control for MIMO feedback control design. The authors present equivalent MIMO feedback loops which Youla parameterization technique could be utilized either directly (Internal Model Control) or utilized to compute a MIMO feedback controller. In neoclassical control, the performance and robustness criteria are achieved by direct frequency loop‐shaping of three different closed‐loop transfer function matrices, Youla, sensitivity, and complementary sensitivity. The authors then investigate the performance and robustness criteria for MIMO feedback controller design. They also extend their MIMO control design approach to unstable plants.