Improved H-Infinity Hybrid Model Predictive Fault-Tolerant Control for Time-Delayed Batch Processes Against Disturbances

Hui Yi,Ziyi Chen

doi:10.1109/access.2020.2986890

Hui Yi, Ziyi Chen

Open Access

https://doi.org/10.1109/access.2020.2986890

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Journal: IEEE Access	Publication Date: Jan 1, 2020
Citations: 4	License type: CC BY 4.0

Affiliation: Hainan Normal University, Nanjing Tech University

Abstract

An H-infinity model predictive fault-tolerant control strategy is proposed for multi-phase batch processes with interval delay and actuator failures. First, state variables, state errors and output tracking errors are introduced to establish an extended-state-space switched system model. Then, based on this model, a predictive fault-tolerant control law is designed for tracking the set point by the output that satisfies the requirements of the optimal performance index under input and output constraints. The feasibility conditions for the solvability of the control law are presented in the form of linear matrix inequalities. In addition, the designed switching law is constructed, and the gain of the control law is obtained via the optimization algorithm. This design has several advantages: the output tracking is faster, the tracking performance is superior, and the trace is smoother at the switching time. Finally, through a comparison with traditional methods, the effectiveness and feasibility of this method are demonstrated via injection molding simulation.

Highlights

As industrial production models exhibit a variety of characteristics, such as small scale, diversity, high added value and technological intensiveness, batch production technology has attracted increasing attention and has begun to play an important role in many fields
If the control process involves uncertainties and external perturbations, the stability of Model predictive control (MPC) will be negatively affected, while the H-infinity model predictive control strategy [31], [32] can analyze the stability of uncertain closed-loop systems, reduce the impact of perturbations on the system’s control performance, and enable the controlled objects to remain robust to external perturbations
The model is transformed into a switched system, and the injection phase and packing phase of the injection molding process are controlled based on the principle of predictive fault-tolerant control under the conditions of time delay, perturbations and actuator faults

Summary

INTRODUCTION

As industrial production models exhibit a variety of characteristics, such as small scale, diversity, high added value and technological intensiveness, batch production technology has attracted increasing attention and has begun to play an important role in many fields. Many studies have considered batch processes, the high-precision control of modern industrial processes remains a challenge One reason for such challenges is the occurrence of time delays and perturbations, which may deteriorate the tracking performance and result in reduced production efficiency [1]–[3]. If the control process involves uncertainties and external perturbations, the stability of MPC will be negatively affected, while the H-infinity model predictive control strategy [31], [32] can analyze the stability of uncertain closed-loop systems, reduce the impact of perturbations on the system’s control performance, and enable the controlled objects to remain robust to external perturbations This paper proposes an improved H-infinity hybrid model predictive fault-tolerant control method for time-delayed batch processes against disturbances.

PROBLEM DESCRIPTION

DESIGN OF THE PREDICTIVE FAULT-TOLERANT CONTROLLER

SIMULATION

CONCLUSION