Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Kiyota, Taiga, Sato, Kazuhiro
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:https://arxiv.org/abs/2504.21341
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866918274491482112
author Kiyota, Taiga
Sato, Kazuhiro
author_facet Kiyota, Taiga
Sato, Kazuhiro
contents Set-point tracking for systems with unknown model parameters is a fundamental problem in control, and two-degree-of-freedom (2DOF) Proportional-Integral (PI) controllers -- consisting of a feedforward controller and PI controller -- are widely employed for this task. In this paper, we propose a model-free design of 2DOF PI controllers, establish its theoretical properties, and compare them with a model-based method from both theoretical and numerical perspectives. For the feedforward design, we extend an existing model-free algorithm to systems subject to Gaussian process and measurement noises. We derive a nonasymptotic lower bound on the required control input/output data length and characterize the resulting estimation error. For PI gain tuning, we formulate a constrained optimization problem and establish sample complexity of a zeroth-order optimization method. Moreover, we quantify how inaccuracies in the feedforward design propagate to the performance of the PI controller, highlighting an interaction that has not been examined in prior work. We further provide a theoretical comparison between the proposed method and the model-based method. In particular, for PI gain tuning, the proposed method is computationally more efficient by avoiding explicit gradient computations. Numerical experiments demonstrate that the 2DOF PI controller designed by the proposed method exhibits better control performance than the model-based method.
format Preprint
id arxiv_https___arxiv_org_abs_2504_21341
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Model-Free Design and Analysis of 2DOF PI Controller for Noisy LTI Systems
Kiyota, Taiga
Sato, Kazuhiro
Optimization and Control
Set-point tracking for systems with unknown model parameters is a fundamental problem in control, and two-degree-of-freedom (2DOF) Proportional-Integral (PI) controllers -- consisting of a feedforward controller and PI controller -- are widely employed for this task. In this paper, we propose a model-free design of 2DOF PI controllers, establish its theoretical properties, and compare them with a model-based method from both theoretical and numerical perspectives. For the feedforward design, we extend an existing model-free algorithm to systems subject to Gaussian process and measurement noises. We derive a nonasymptotic lower bound on the required control input/output data length and characterize the resulting estimation error. For PI gain tuning, we formulate a constrained optimization problem and establish sample complexity of a zeroth-order optimization method. Moreover, we quantify how inaccuracies in the feedforward design propagate to the performance of the PI controller, highlighting an interaction that has not been examined in prior work. We further provide a theoretical comparison between the proposed method and the model-based method. In particular, for PI gain tuning, the proposed method is computationally more efficient by avoiding explicit gradient computations. Numerical experiments demonstrate that the 2DOF PI controller designed by the proposed method exhibits better control performance than the model-based method.
title Model-Free Design and Analysis of 2DOF PI Controller for Noisy LTI Systems
topic Optimization and Control
url https://arxiv.org/abs/2504.21341