Dual-Rate Data-Driven Virtual Reference Feedback Tuning: Improvement in Fast-Tracking Performance and Ripple-Free Design

Takao Sato,Orlando Arrieta,Natsuki Kawaguchi,Yuta Sakai

doi:10.1109/access.2021.3122234

Takao Sato, Orlando Arrieta + Show 2 more

Open Access

https://doi.org/10.1109/access.2021.3122234

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Journal: IEEE Access	Publication Date: Jan 1, 2021
Citations: 6	License type: CC BY 4.0

Affiliation: Universidad de Costa Rica, University of Hyogo

Abstract

In this study, a data-driven design method is proposed for a dual-rate system, where the sampling interval of a plant output is restricted and is an integer multiple of the holding interval of a control input. In our proposed method, single-rate virtual reference feedback tuning (S-VRFT), where the holding interval is the same as the sampling interval, is extended to the dual-rate virtual reference feedback tuning (D-VRFT) system. In D-VRFT, a controller is decided using a set of input/output data used in S-VRFT, and it is easy to extend S-VRFT to D-VRFT and implement D-VRFT. In this study, intersample oscillations caused in such a dual-rate control system is prevented because a weighting filter is introduced for penalizing the control input deviation between the sampling instants. The filter is designed as an integrator for weighting the low-frequency domain. The improvement in fast-tracking performance as well as the ripple-free property are demonstrated through both the numerical and experimental results.

Highlights

In a control approach, the performance of controllers can be estimated without mathematical models or prior knowledge of the plant [1], [2]
Sato et al.: Dual-Rate Data-Driven Virtual Reference Feedback Tuning: Improvement in Fast-Tracking Performance and Ripple-Free Design time systems, wherein discrete-time control input decided by a digital computer is updated at a high frequency whereas the continuous-time plant output is sampled at a low frequency
In V-A, the intersample ripple occurred using dual-rate virtual reference feedback tuning (D-virtual reference feedback tuning (VRFT)) with Wu(z−1) = 0 is resolved by penalizing the control input deviation, and a software-based solution is given

Summary

INTRODUCTION

The performance of controllers can be estimated without mathematical models or prior knowledge of the plant [1], [2]. A dual-rate data-driven design method is proposed for controlling SISO continuous-. Sato et al.: Dual-Rate Data-Driven Virtual Reference Feedback Tuning: Improvement in Fast-Tracking Performance and Ripple-Free Design time systems, wherein discrete-time control input decided by a digital computer is updated at a high frequency whereas the continuous-time plant output is sampled at a low frequency. In contrast to the conventional dual-rate method, the proposed method, based on the VRFT approach, requires only a set of input/output data. The proposed dual-rate design method is implemented using the same data used in the conventional VRFT for the single-rate system In such dual-rate control systems, the plant output might oscillate between the sampling instants even when there is no steady-state error at sampling instants [31], [32].

SINGLE-RATE DESIGN

MOTIVATION

DUAL-RATE DESIGN

SIMULATION EXAMPLE

EXPERIMENT

RIPPLE SUPPRESSION BY HARDWARE MODIFICATION

CONCLUSIONS