This book presents multi-stage feedback control designs for the system with multi-time-scale behaviour both in the continuous time domain and discrete-time domain. Multi-time-scale systems have widely separated clusters of eigenvalues, making the system matrices ill-conditioned. Due to this the direct design of a feedback controller and reduced- or full-order observers for such systems is a challenging task. Hence, the feedback controllers and observers are designed in multiple design stages, i.e. two-stage design for the two-time-scale system and three-stage design for the three-time-scale system. In this book, multi-stage feedback controller and observer designs are proposed for the three-time-scale system to reduce offline and online computational efforts. The applicability of these methods is demonstrated by simulating practical systems like a coal-fired power plant and a nuclear power plant.
This book also discusses the design of multi-stage feedback controllers in discrete time. The design of state feedback control for a multi-time-scale system with a lower sampling rate fails to capture information in the fastest (very fast) and fast states. While sampling at a higher rate increases computation time. Thus, the use of single-rate sampling for such systems is unsuitable. Therefore, multi-rate state feedback controllers are designed for the multi-time-scale system, in which slow, fast, and very fast states are sampled at different sampling rates. As slow, fast and very fast states are the decoupled and internal states of the original system, these are estimated by the sequential multi-stage observers. Applications of these multirate designs to the numerical examples are demonstrated and simulations are compared with single-rate sampling methods. The methods suggested in this book result in considerable savings in online and offline computations, reduction in design complexity, and improvement in robustness and closed-loop performance. This book can be beneficial to mathematicians, scientists, researchers and practicing engineers working in this area.
Dr. Ravindra Munje holds a B.E., M.E., and Ph.D. degree from Mumbai University in 2005, Pune University in 2009, and Swami Ramanand Teerth Marathwada University in 2015 respectively. He completed his post-doctoral fellowship at Shanghai Jiao Tong University in Shanghai from June 2017 to May 2019. During his fellowship, he received research funds of approximately 15 lakh rupees from the National Natural Science Foundation of China as an International Young Scientist. Currently, Dr. Munje is a Professor and head of the Electrical Engineering Department at K. K. Wagh Institute of Engineering Education and Research in Nashik, India. He also holds the position of Dean (Research and Development) at the institute. He has authored a book and about 60 refereed papers, with his research interests focusing on modeling and control of large-scale systems using sliding mode and multi-rate output feedback. He has also supervised 8 PG students and is currently guiding 4 Ph.D. students. Dr. Munje has been recognized with several awards, including the Promising Engineer Award in 2016, the Outstanding Researcher Award in 2018, and the Best Faculty Award in 2019. Recently, he was awarded the prestigious ‘Best Teacher Award’ of Savitribai Phule Pune University in February 2024. He is a senior member of IEEE, a member of IET, and a life member of ISTE.
Dr. Balasaheb M. Patre completed a Bachelor of Instrumentation Engineering in 1986 and, a Masters of Instrumentation Engineering in 1990, both from SGGS Institute of Engineering and Technology, Vishnupuri, Nanded, and Ph. D. from Indian Institute of Technology (IIT), Bombay in 1998. Currently, he is working as a Professor at the Department of Instrumentation Engineering, SGGS Institute of Engineering and Technology, Vishnupuri, Nanded, Maharashtra. He has published more than 80 International Journal Papers, more than 100 National and International Conference papers, 6 Books, and 5 Book Chapters. He is a reviewer for 45 international (SCI/SCIE indexed) peer-reviewed journals. He has completed sponsored research projects from DST, AICTE, BARC, BRNS, and NRB. He has so far supervised 22 students for Ph. D. and 5 students are currently pursuing Ph. D. under his guidance in the areas of systems and control engineering in general and robust control, nuclear reactor control, sliding mode control and applications, and process control in particular. Dr. Patre is a senior member of IEEE, a Fellow of the Institution of Engineers (India), a Member of IETE (India), and a life member of ISTE.
Dr. Weidong Zhang received his BS, MS, and Ph.D. degrees from Zhejiang University, China, in 1990, 1993, and 1996, respectively, and then worked as a Postdoctoral Fellow at Shanghai Jiaotong University. He joined Shanghai Jiaotong University in 1998 as an Associate Professor and has been a Full Professor since 1999. From 2003 to 2004, he worked at the University of Stuttgart, Germany, as an Alexander von Humboldt Fellow. He is a recipient of the National Science Fund for Distinguished Young Scholars of China. In 2011 he was appointed Chair Professor at Shanghai Jiaotong University. He is currently the Director of the Engineering Research Center of Marine Automation, Municipal Education Commission. His research interests include control theory and its applications in industry and ocean engineering. He is the author of more than 300 refereed papers and 1 book and holds 32 patents.
