Finite-Horizon H-Infinity Control for Time-Varying State-Saturated Systems under Stochastic Communication Protocol

Kewang Huang,Feng Pan,Yuqiang Wu

doi:10.1155/2021/4746825

Abstract

In this paper, the H∞ control problem is investigated for a class of time-varying state-saturated systems with both stochastic parameters and nonlinearities under the stochastic communication protocol (SCP). The sensor-to-controller network is considered where only one sensor can obtain access to the communication network at each transmission instant. The SCP is adopted to mitigate the undesirable data collision phenomenon. The model transformation technique is employed to simplify the addressed problem, and then, the completing squares method is carried out to obtain a sufficient condition for the existence of the finite-horizon H∞ controller. The controller parameters are characterized by solving two coupled backward recursive Riccati-like difference equations. A simulation example is finally utilized to illustrate the effectiveness of the proposed controller design scheme.

Highlights

Due to its advantages of easy sharing, strong flexibility, and easy installation and maintenance, networked control systems (NCSs) have attracted a large number of scholars’ attention in recent years [1,2,3,4].Most existing methods of the controller and the filter design are only for infinite time-invariant controlled object
In the actual NCSs, due to the operating point offset, equipment aging, and environmental factors, many systems are time varying. erefore, it is of more practical significance to study the transient characteristics of time-varying systems in the finite horizon than the steady-state characteristics of timeinvariant systems. e corresponding fuzzy control problem, finite-time domain filtering problem, and envelope constraint problem for continuous time-varying system, discrete timevarying system, and discrete time-varying nonlinear system are discussed in [5,6,7], respectively
The control and filtering of NCSs in infinite time domain and random communication protocol have been studied in depth, the control problem in finite-time domain of state-saturated time-varying system has not attracted attention under the influence of random communication protocol, which arouses the author’s research interest

Summary

Introduction

Due to its advantages of easy sharing, strong flexibility, and easy installation and maintenance, networked control systems (NCSs) have attracted a large number of scholars’ attention in recent years [1,2,3,4]. Mechanical systems with position and speed limits, digital filters implemented in finite word length formats, and neural networks with saturated transfer functions [17, 18] In these cases, the state of the system is constrained within a bounded set. The control and filtering of NCSs in infinite time domain and random communication protocol have been studied in depth, the control problem in finite-time domain of state-saturated time-varying system has not attracted attention under the influence of random communication protocol, which arouses the author’s research interest. This paper is concerned with the control problem of the state saturation system in the finite-time domain based on the random communication protocol and considering the influence of random parameters and random nonlinearity. If their dimensions are not explicitly stated, they are assumed to be compatible for algebraic operations. e notation P > 0 (≥0) means that P is a symmetric and positive definite (semidefinite) matrix. 0 and I represent the zero matrix and identity matrix with compatible dimensions

Problem Description

H‘ Performance Analysis

Numerical Example

Conclusion