U-model enhanced control of non-minimum phase systems

Abstract

Control of non-minimum phase (NMP) dynamic systems has been a widely and intensively studied challenging topic from its academic research to industrial applications. With the emergence of U-model based control system design, this study presents a new solution in designing such control systems. In technique, different from pole-zero cancellation (i.e. in force of multiplication/division), this study proposes a pulling principle (i.e. in force of summation/subtraction) to relocate zeros and poles through Infinite Impulse Response (IIR) filters, then introduces a U-model based universal control framework with invariant controller plus U-model inverter so that it separates the treatment of NMP issue from stable control system design. By integration of the above techniques, this study presents a systematic procedure to complement those classical approaches in designing NMP control systems. The associated properties and performance are proved analytically and demonstrated numerically (with Matlab simulation of bench test examples). To follow the study, the computational experiment results provide a user-friendly step by step procedure for the readers/users with interest in their ad hoc applications.

KEYWORDS:

• Non-minimum phase (NMP) systems
• zero and pole pulling
• IIR filters
• U-model based control systems design
• U-control

Acknowledgements

The authors are grateful to the editors and the anonymous reviewers for their helpful comments and constructive suggestions with regard to the revision of the paper.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Quanmin Zhu

Quanmin Zhu is Professor in control systems at the Department of Engineering Design and Mathematics, University of the West of England, Bristol, UK. He obtained his MSc in Harbin Institute of Technology, China in 1983 and PhD in Faculty of Engineering, University of Warwick, UK in 1989. His main research interest is in the area of nonlinear system modelling, identification, and control. He has published over 250 papers on these topics, edited various books with Springer, Elsevier, and the other publishers, and provided consultancy to various industries. Currently Professor Zhu is acting as Editor of International Journal of Modelling, Identification and Control, Editor of International Journal of Computer Applications in Technology, Academic Editor of Complex, Hindawi, Member of various journal editorial boards, and Editor of Elsevier book series of Emerging Methodologies and Applications in Modelling, Identification and Control. He is the founder and president of a series annual International Conference on Modelling, Identification and Control.

Ji Qiu

Ji Qiu was born in Nanning, China, in 1992. She received the BEng degree with first class honours in 2015 and the PhD degree in 2020 from University of the West of England, Bristol, United Kingdom. She was an instructor from 2016 to 2020 and an associate lecturer from 2019–2020 at Department of Engineering Design and Mathematics, University of the West of England, Bristol, United Kingdom. She serves as a peer reviewer for the International Journal of Robust and Nonlinear Control and the International Journal of Computer Applications in Technology.

Iman Delshad

Iman Delshad received his Ph.D. degree in Automatic Control from Luleå University of Technology in 2015. After several years in academia and holding different positions as postdoctoral researcher and lecturer in control systems, he is currently working as senior embedded software developer at ABB Robotics in Sweden. His research interests include machine learning, perception and robotics.

Mokhtar Nibouche

Mokhtar Nibouche received his “ingéniorat d’état” in Electrical and Electronic Engineering (control) from Ecole Nationale Polytechnique d’Alger (Algiers) in 1990 and a “Magistére” in Electrical and Electronic Engineering in 1994 from the same institution. Mokhtar Nibouche received his PhD degree in computer science for the Queen’s University of Belfast, UK in 2002. Currently, he is a senior lecturer and a member of the engineering modelling and simulation research group with the Department of Engineering Design and Mathematics at University of the West of England, Bristol, UK. Mokhtar research interests include General Signal Processing, Real Time Signal Processing and Embedded Systems, Biologically Inspired Systems, Control, Some Aspects of Robotics.

Yufeng Yao

Yufeng Yao received his BENG in Applied Mechanics from National University of Defence Technology in 1984, and M.Sc. degree in Computational Aerodynamics from Nanjing University of Aeronautics and Astronautics in 1987, respectively. Later he received his Ph.D. degree in Aerospace Engineering from Glasgow University, UK in 1997. He is currently a full professor and head of engineering modelling and simulation research group with the Department of Engineering Design and Mathematics at University of the West of England, Bristol, UK. His research interests include nonlinear dynamics, flow analysis and control, numerical algorithm development and application for complex engineering systems.