Soumitro Banerjee Professor, Department of Electrical Engineering Indian Institute of Technology, Kharagpur-721302, India Tel: +91-3222-283030 (Off), +91-3222-283031 (Res.) Fax: +91-3222-255303/282262 Email: soumitro@ee.iitkgp.ernet.in

Background:

Awards:

• Shanti Swarup Bhatnagar Award (2003)
  by the Council for Scientific and Industrial Research (CSIR), India
• Citation Laureate Award (2004)
  Identified as highly cited researcher by Thomson Scientific, and listed in http://www.isihighlycited.com
• Fellow of the Indian National Academy of Engineering (INAE), 2004
• Fellow of the Indian Academy of Sciences, Bangalore, 2005
• Fellow of the Indian National Science Academy (INSA), Delhi, 2007
• Senior Member, IEEE

Teaching:

• EE30016: Dynamics of physical systems (Electrical Engineering, 3rd year)
• EE23001: Signals and Networks (EE, E&ECE, CSE, 2nd year)
• EG20001: Energy Resources and Technology (Energy Engineering, 2nd year)
• EE60064: Chaos, Fractals, and Dynamical Systems (Open elective)
• EG40001: Nonconventional Electrical Power Generation (Energy Engineering, 4th year)

Lab developed:

• Energy Systems Laboratory

Research:

My research interests are in bifurcation theory and chaos.

Scientists studying changes taking place in the material world have found that the changes can be quantitative as well as qualitative. Such qualitative changes are found both in its state of existence (like ice turning into water), and in its state of motion (like a regular periodic behaviour changing into an aperiodic and unpredictable one). The qualitative changes in the state of motion are called bifurcations --- which have been the subject of my investigation.

I have studied these bifurcation phenomena in a particular class of dynamical system which involves some kind of switching action that makes the system toggle between two or more different types of dynamical behaviour. Common examples of such ``hybrid systems'' are the switching electronic circuits, mechanical systems where impacts between bodies take place, the human heart, etc. I have shown that such systems undergo a special kind of qualitative change, known as "border collision bifurcation." I have played some role in developing the theory of border-collision bifurcations, which has been widely used in application areas to understand why certain abrupt and drastic changes occur in the dynamical state of a system when a parameter is smoothly varied.

I have also focused on nonlinear phenomena in power electronics, demonstrating and studying the mathematical basis of many atypical bifurcation phenomena observed in the field of power electronics.

Those who want a bit more technical details may download this.

Other activities:

Some important publications

Books

1. S. Banerjee and G. C. Verghese (Ed.) ``Nonlinear Phenomena in Power Electronics --- Attractors, Bifurcations, Chaos, and Nonlinear Control,'' IEEE Press, 2001. See details and the Wiley link

   (Contributed by more than 30 researchers, this book puts together all the available knowledge in the field upto the year 2000. The edited volume has already become the starting point for many new entrants to the field, and a window to the body of knowledge for the power electronics industry.)

2. S. Banerjee, ``Dynamics for Engineers,'' John Wiley & Sons, UK, 2005 See details and Wiley link

   (The current undergraduate textbooks on dynamics and control are heavily biased toward linear systems, with nonlinearity treated as oddity --- though in reality most physical and engineering systems are nonlinear. This sophomore-level textbook is aimed to address this problem, first by introducing those methodologies of system modeling that make no reference to linearity, and then by developing an understanding of dynamics where linear system description is put in proper perspective --- as local linear approximation in the neighborhood of an equilibrium point.)

3. S. N. Bhadra, D. Kastha, and S. Banerjee, "Wind Electrical Systems," Oxford University Press, New Delhi, 2005

   (Electrical power generation from non-conventional energy sources is now a part of curriculum in many institutions. But very few books address the electrical engineering problems of integrating such sources with the grid. This is the first Indian book of its kind specifically addressing these issues.)

Research papers

2009:

• "Invisible grazings and dangerous bifurcations in impacting systems: The problem of narrow-band chaos" by Soumitro Banerjee, James Ing, Ekaterina Pavlovskaia, Marian Wiercigroch, and Ramesh K. Reddy Physical Review E, vol. 79, p.037201 (2009)

2008:

• "Application of Filippov method for the analysis of subharmonic instability in dc–dc converters" by D. Giaouris, S. Maity, S. Banerjee, V. Pickert, and B. Zahawi International Journal Circuit Theory & Applications, vol. 55, 1084-1096 (2008)
• "The nature of the normal form map for soft impacting systems" by Yue Ma, James Ing, Soumitro Banerjee, Marian Wiercigroch, and Ekaterina Pavlovskaia International Journal on Nonlinear Mechanics, vol. 43, 504-513 (2008)
• "On the Existence of Low-Period Orbits in n-Dimensional Piecewise Linear Discontinuous Maps" by Partha Sharathi Dutta, Bitihotra Routroy, Soumitro Banerjee and S. S. Alam Nonlinear Dynamics, Vol. 53, 369-380 (2008)
• "Transitions from phase-locked dynamics to chaos in a piecewise-linear map" by Z. T. Zhusubaliyev, E. Mosekilde, S. De, and S. Banerjee, Physical Review E, 77, 026206 (2008)
• "Stability Analysis of the Continuous Conduction Mode Buck Converter via Filippov's Method" by D. Giaouris, S. Banerjee, B. Zahawi, and V. Pickert, IEEE Transactions on Circuits & Systems I, (2008)
• "Experimental study of impact oscillator with one-sided elastic constraint" by J. Ing, E. Pavlovskaia, M. Wiercigroch, and S. Banerjee, Philosophical Transactions of the Royal Society of London, Part A, 366, 679-704 (2008)
• "Character of the map for switched dynamical systems for observations on the switching manifold" by Rangoli Sharan and Soumitro Banerjee, Physics Letters A, doi:10.1016 (2008)

2007:

• "Control of Fast Scale Bifurcations in Power Factor Correction Converters" by D. Giaouris, S. Banerjee, B. Zahawi, and V. Pickert, IEEE Transactions on Circuits & Systems II, 54, 805-809 (2007)
• "Codimension-three bifurcations: Explanation of the complex one-, two-, and three-dimensional bifurcation structures in nonsmooth maps" by Viktor Avrutin, Michael Schanz, and Soumitro Banerjee, Physical Review E, Vol.75, No.6 (2007)
• "Bifurcation Analysis of PWM-1 Voltage-mode Controlled Buck Converter using the Exact Discrete Model" by Somnath Maity, Divyendu Tripathy, Tapas K. Bhattacharya, and Soumitro Banerjee, IEEE Transactions on Circuits & Systems -- I, Vol.54, No.5 (2007)

2006:

• "Border Collision Bifurcations in a Soft Impact System" by Yue Ma, Manish Agarwal, and Soumitro Banerjee, Physics Letters A, Vol. 354, No.4 (2006)
• "Multi-parametric bifurcations in a piecewise-linear discontinuous map" by Viktor Avrutin, Michael Schanz, and Soumitro Banerjee,, Nonlinearity, Vol.19, pp.187 (2006)

2005:

• "Dangerous bifurcation at border collision --- when does it occur?" by Anindita Ganguli and Soumitro Banerjee, Physical Review E, 71 (2005)
• "Dynamics of a piecewise smooth map with singularity" by Aloke Kumar and Soumitro Banerjee, Physics Letters A, 337 (2005)
• "Experimental verification of border collision bifurcation due to mode transition in a current mode controlled buck converter" by S. Parui, S. Banerjee, S. Sengupta, and B. Basak, Journal of Circuits, Systems, and Computers, Vol.14, pp. 653-666 (2005)

2004:

• "Dynamical Effects of Missed Switching in Current-Mode Controlled dc-dc Converters" by Soumitro Banerjee, Sukanya Parui, and Amit Gupta, IEEE Transactions on Circuits & Systems -- II, 51 (2004)
• "Analysis and CMOS implementation of a chaos-based communication system" by Soumyajit Mandal and Soumitro Banerjee, IEEE Transactions on Circuits & Systems -- I, 51 (2004)
• "Minimizing electromagnetic interference problems with chaos" by S. Banerjee, A. L. Baranovski, J. L. R. Marrero, and O. Woywode, IEICE Transactions on Fundamentals, 87 (2004)

Some older papers

1. Krishnendu Chakrabarty, Goutam Poddar and Soumitro Banerjee, ``Bifurcation Behaviour of the Buck Converter'', IEEE Transactions on Power Electronics, Vol.11, No.3, May 1996, pp.439-447.
2. Soumitro Banerjee and Krishnendu Chakrabarty, ``Nonlinear Modeling and Bifurcations in the Boost Converter'', IEEE Transactions on Power Electronics, Vol.13, No.2, March 1998, pp.252-260.
3. Soumitro Banerjee, ``Coexisting Attractors, Chaotic Saddles and Fractal Basins in a Power Electronic Circuit'', IEEE Transactions on Circuits & Systems -- I, Vol.44, No.9, September 1997, pp.847-849.

These papers report the initial investigation on the dynamic behavior of dc-dc converters, which showed some peculiar features specific to switching circuits.

1. S. Banerjee, E. Ott, J. A. Yorke, G-H. Yuan, “Anomalous Bifurcations in dc-dc Converters: Borderline Collisions in Piecewise Smooth Maps,” IEEE Power Electronics Specialists' Conference, St. Louis, Missouri, USA, 22-27 June 1997, pp.1337-1344.
2. G-H. Yuan, S. Banerjee, E. Ott and J.A. Yorke, “Border-collision Bifurcations in the Buck Converter,” IEEE Transactions on Circuits & Systems -- I, Vol.45, July 1998, pp.707-716.

1. S. Banerjee, C. Grebogi, ``Border Collision Bifurcations in Two-Dimensional Piecewise Smooth Maps'', Physical Review E, Vol.59, No. 4, April 1999, pp.4052-4061. download
2. S. Banerjee, M. S. Karthik, G. H. Yuan and J. A. Yorke, ``Bifurcations in one-dimensional piecewise smooth maps --- theory and applications in switching circuits'', IEEE Transactions on Circuits & Systems -- I, Vol. 47, No. 3, March 2000, pp. 389-394. download
3. S. Banerjee, P. Ranjan and C. Grebogi, ``Bifurcations in two-dimensional piecewise smooth maps --- theory and applications in switching circuits'', IEEE Transactions on Circuits & Systems -- I, Vol. 47, No. 5, May 2000, pp. 633-643. download
4. S. Banerjee, J. A. Yorke and C. Grebogi, ``Robust Chaos'', Physical Review Letters, Vol.80, No.14, 6 April 1998, pp. 3049-3052. download