Data-Driven Structured Controller Design Using the Matrix S-Procedure
Zhaohua Yang, Yuxing Zhong, Nachuan Yang, Xiaoxu Lyu, Ling Shi
TL;DR
This paper tackles data-driven optimal structured controller design for discrete-time LTI systems under both $H_2$ and $H_\infty$ performance. It builds a data-driven framework that (i) characterizes the set of system matrices $\Sigma$ consistent with collected data using per-sample quadratic constraints and the matrix $S$-Procedure, and (ii) linearizes the nonconvex structure constraint to yield SDP/ILMI solutions. The authors propose three problem variants—model-based structured, data-driven unstructured, and data-driven structured—for each performance metric, with the data-driven cases solved via SDPs and iterative updates to enforce sparsity patterns. Across simulations, the method shows monotonic improvement with longer data length $T$ and outperforms the prior work miller2024data, at the cost of higher computational load. The work advances sparse, robust data-driven control for networked systems by reducing conservatism and enabling explicit structure in the controller.
Abstract
This paper focuses on the data-driven optimal structured controller design for discrete-time linear time-invariant (LTI) systems, considering both the $H_2$ performance and the $H_\infty$ performance. Specifically, we consider three scenarios: (i) the model-based structured control, (ii) the data-driven unstructured control, and (iii) the data-driven structured control. For the $H_2$ performance, we primarily investigate cases (ii) and (iii), since case (i) has been extensively studied in the literature. For the $H_\infty$ performance, all three scenarios are considered. For the structured control, we introduce a linearization technique that transforms the original nonconvex problem into a semidefinite programming (SDP) problem. Based on this transformation, we develop an iterative linear matrix inequality (ILMI) algorithm. For the data-driven control, we describe the set of all possible system matrices that can generate the sequence of collected data. Additionally, we propose a sufficient condition to handle all possible system matrices using the matrix S-procedure. The data-driven structured control is followed by combining the previous two cases. We compare our methods with those in the existing literature and demonstrate our superiority via several numerical simulations.
