Isomorphism-based robust right coprime factorisation of non-linear unstable plants with perturbations

2015 International Conference on Advanced Mechatronic Systems (ICAMechS)

2015

This paper is concerned with passivity-based robust control and tracking performance for nonlinear feedback system with unknown perturbations. By designing the feedforward controller in smaller norm, not only the nonlinear system with nominal plant but also that with perturbed plant can be stabilized, moreover, the plant output can be proved to be closer to the reference output. The effectiveness of the proposed is confirmed by the simulation results.

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Passivity-based robust control for uncertain nonlinear feedback systems

2015 International Conference on Advanced Mechatronic Systems (ICAMechS)

2015

“…Generally, robust control is to find a stabilizing controller to stabilize the nominal plant as well as the perturbed plant if the perturbations are bounded. There are many methods to deal with the robust issues in many fields, such as LMI method [8], sliding mode control method [10], robust right coprime factorization method [1][2][3][4][5]9] and so on. Among these methods, the robust right coprime factorization method is effective to deal with the robust issue and it has been proved to be a promising method in the control and design of the nonlinear systems with uncertainties where the uncertainties mainly consists of additive non-parametric uncertainties and disturbances.…”

Section: Introductionmentioning

confidence: 99%

“…It is evident that without knowing the factors of the nonlinear plant, it is impossible to study the coprime factorization of the plant except some special cases. Therefore, in [3], we first considered the factorization method by using isomorphism and the existence of the controllers was also concerned. Later, we continued to study the qualitative design scheme of the robust controllers where a sufficient condition was proposed to guarantee the robust stability and the perfect tracking property [1] .…”

Section: Introductionmentioning

confidence: 99%

Operator-based robust control for nonlinear feedback systems with noise disturbance

Liu

Proceedings of the 2013 International Conference on Advanced Mechatronic Systems

2013

This paper is concerned with the robust stability and output tracking problems of perturbed nonlinear feedback control systems with noise disturbance using operator-based robust right coprime factorization method. After factorization by isomorphism, the robustness of the perturbed plant can be linked into the robust stability of the whole nonlinear feedback systems with noise disturbance. By designing the controllers to satisfy the proposed sufficient conditions, the robust stability of the perturbed nonlinear feedback systems can be guaranteed. Meanwhile, the plant output can asymptotically track to the reference output. The effectiveness of the proposed method is confirmed by the simulation results.

“…Among these methods, operator-based robust right coprime factorisation approach is an interesting one. It provides an effective framework for non-linear unstable system, which has attracted much attention due to its effectiveness (Figueiredo and Chen, 1993;Han and Chen, 2002;Chen and Figueiredo, 2002;Deng et al, 2004Deng et al, , 2008Deng et al, , 2009Verma, 1984;Deng and Bu, 2010). In robust right coprime factorisation approach, non-linear plant behaviour is represented as operator.…”

Section: Introductionmentioning

confidence: 99%

Operator-based non-linear control system design for unstable plants with input saturation

Umemoto

2011

IJAMECHS

Operator-based robust right coprime factorisation approach is an interesting approach for non-linear control. It provides an effective framework for non-linear unstable system. In practice, the input constraint always exists, which induces that the real control input is different from the controller output, thus the input constraint may destabilise the system. However, control system design for non-linear plants with input saturation has seldom been studied due to the difficulties in dealing with non-linearity. Also in operator-based robust right coprime factorisation method, input saturation is not considered. In this paper, a new control system design for non-linear unstable plants with input saturation is proposed. Based on the robust right coprime factorisation, an operator-based switching controller is designed, which avoids the unstable region. Moreover, based on the proposed design scheme, the output tracking performance is also realised, and the effectiveness of the proposed method is verified by simulation.Reference to this paper should be made as follows: Umemoto, K. and Deng, M. (2011) 'Operator-based non-linear control system design for unstable plants with input saturation', Int. University, where he was an Assistant Professor and then an Associate Professor. His research interests include living body measurement; operator-based non-linear system modeling, control and fault detection; strong stability-based control; and robust parallel compensation. This paper is a revised and expanded version of a paper entitled 'Nonlinear control system desing for unstable plants with input saturation using robust right coprime factorization' presented at the