A Robust Nonlinear Controller With Low-Gain-State-Observer for Wire Rope Tension Active Control of Hoisting Systems

Xiang Li,Dong Cheng,Gang Shen,Yu Tang,Zhencai Zhu

doi:10.1109/access.2020.2972750

Abstract

In this paper, a modified double-rope winding hoisting system (MDWHS) is proposed for ultra-deep mines. Nevertheless, the MDWHS has wire rope tension imbalance issues due to lift inconsistency of two wire ropes. A combined control algorithm is designed for wire rope tension active control considering the nonlinear uncertainties subjected to the MDWHS, where a low gain state observer (LGSO) and a robust nonlinear adaptive controller are employed via backstepping theory. Firstly, to investigate the wire rope tension active control method, the dynamics model of the MDWHS is established. Then, the LGSO is employed to estimate unmeasured system state variables and to optimize perturbed system state variables. Finally, a robust nonlinear control method is employed to acquire prospective control input. The combined control algorithm can ensure the desired transient and final tracking accuracy, which is essential for tracking control of wire rope tension active adjustment. The stability of the overall closed-loop system with the presented control algorithm can be verified referring to the Lyapunov theory. Experimental results conducted on the established double-rope winding hoisting simulation experimental system demonstrate that the proposed active control method exhibit more advantageous performance on wire rope tension balance control compared with the conventional Proportion Integration (PI) and adaptive backstepping controller (ABC).

Highlights

Mine hoisting systems are essential for mines, which are employed to carry payloads [1] and transport personnel [2]
adaptive backstepping controller (ABC): Considering the parameter uncertainties and external disturbance, the ABC was applied for wire rope tension active control owing to backstepping technology and adaptive law
It is can be seen that the estimated state variables contain fewer high-frequency components while the proposed controller is employed, which indicates that the low gain state observer (LGSO) can remove the high-frequency noise associated with the measurement signal obtained by the sensor

Summary

INTRODUCTION

Mine hoisting systems are essential for mines, which are employed to carry payloads [1] and transport personnel [2]. Literature [19] addresses the problem of adaptive neural output-feedback decentralized control for a class of strongly interconnected nonlinear systems suffering stochastic disturbances and an observer-based adaptive backstepping decentralized controller is developed. To adjust the wire rope tension of the MDWHS actively, a novel control algorithm combined with a nonlinear adaptive robust controller and an LGSO is presented. The LGSO can eliminate high-frequency interference signals of measured or differential values On this basis, combined with the designed LGSO, a robust nonlinear adaptive control input composed of the reference signal, adaptive parameters, measured and estimated state variables are obtained.

DYNAMICS MODEL OF THE MDWHS

LOW-GAIN-STATE-OBSERVER DESIGN

ROBUST NONLINEAR CONTROLLER DESIGN

CONCLUSION