Practical Application of Fractional-Order PID Controller based on Evolutionary Optimization Approach for a Magnetic Levitation System

Abstract

This article proposes a state-of-the-art design procedure of integer-order PID (IOPID) and fractional-order PID (FOPID) controller applied to a well-established and diversified engineering application of the Magnetic Levitation System (Maglev). Controller design and implementation for the Maglev system are quite complicated and difficult since the system dynamics exhibits non-linearity with a wide variation of operating points. Also, the system is highly unstable which rules out the possibility to accomplish conventional tuning techniques. Thus in this work, the controller tuning methodology is framed as a complex optimization problem by incorporating a new transient specification-based objective function. For designing and tuning of proposed controller parameters, modern meta-heuristic and evolutionary optimization algorithms are deployed; those are Bird Swarm Algorithm, Elephant Herding Optimization, Equilibrium optimizer and Grey Wolf Optimization. The software and hardware results demonstrate that FOPID controllers yield better time-domain and frequency-domain performance specifications and exhibit excellent reference tracking capability than IOPID controllers. The performance robustness of the proposed controllers is greatly enhanced subjected to a vast range of parametric uncertainties along with a significant minimization of the control effort.

KEYWORDS:

• Equilibrium optimizer
• Evolutionary optimization algorithms
• FOPID
• Intelligent control system design
• MAGLEV system
• Real-time control
• Robustness analysis

DISCLOSURE STATEMENT

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

Additional information

Notes on contributors

Soham Dey

Soham Dey received the Bachelor of Technology (BTech) degree in electrical engineering from the West Bengal University of Technology, Kolkata, India, in 2012 and the Master of Engineering degree in electrical engineering from the Birla Institute of Technology, Ranchi, India in 2015. He is currently an assistant professor with the Department of Electrical Engineering, Dr B C Roy Engineering College, Durgapur, India. His research interests include an advanced control system, soft computing techniques and optimal control theory.

Subrata Banerjee

Subrata Banerjee (M’04–SM’15) is working as a professor with the Department of Electrical Engineering, National Institute of Technology, Durgapur, India. His research interest includes modeling & control of switch-mode converters and inverters, multilevel inverters & different modulation techniques, electromagnetic levitation, active magnetic bearing, controller design, intelligent control, etc. He has successfully completed a few research and consultancy projects. He has authored about 200 research papers in national/international journals and conference records. He has filed three Indian patents out of which one has been granted. He has guided 11 PhD and 22 MTech students and many are pursuing their degrees under his guidance. Prof Banerjee is the recipient of several academic awards, including 10 nos Best Paper Awards and TATA RAO Prize. He is a Fellow of the Institution of Engineers (India), the Institution of Electronics and Telecommunication Engineers (India), and the Institution of Engineering and Technology (UK), Senior Member IEEE (USA). He is a regular reviewer of IEEE/IET Transactions & also acting as Associate Editor/Editorial Board in IEEE Access (USA), IET Power Electronics (UK)/IEEE Transportation Electrification Community eNewsletter (USA). Email: [email protected]

Jayati Dey

Jayati Dey (M’09) received the BE, ME and PhD degrees in 2000, 2003 and 2007, respectively. She is currently an associate professor in the Department of Electrical Engineering, National Institute of Technology Durgapur, India. Her research interests are periodic compensation, switching power converters, robotics and mechatronics with a special interest in robust control. Email: [email protected]