Dr. Ramesh Oruganti

Dr. Ramesh Oruganti
EMail: ramesho[at]iitmandi[dot]ac[dot]in
Address: School of Computing and Electrical Engineering
IIT Mandi, PWD Rest House 2nd floor,
Near Bus Stand, Mandi - 175001
India
Phone: 01905-237993

Education

  • Ph.D, Virginia Tech, (1987) - Electrical Engineering
  • M.Tech, IIT Madras (1972) - Electrical Engineering
  • B.Tech, IIT Madras (1969) - Electrical Engineering

Work Experience

  • Visiting Professor, IIT Mandi (29th January 2013 onwards).
  • R&D Consultant - (July 2010-Jan 2013).
  • Senior Visiting Fellow, UNSW, Australia (July 2007 to May 2008).
  • Associate Professor/Senior Lecturer, NUS, Singapore (1989-2010).
  • R&D Engineer, Corporate R&D, Schenectady, USA (1987-89).
  • Prior Experience: BHEL, Bangalore, Best & Crompton Engineering Ltd, Madras & IIT, Madras.

Professional Affiliation

    Senior Member, IEEE, USA

Research Interests

    My current research interest is in the area of power electronic applications in renewable electrical energy systems and, in particular, in solar photovoltaic energy systems. The areas which I have been working on together with my students and collaborators over the years are

      Efficient and high performance DC-DC power conversion

    • Resonant & soft-switched power converters
    • Power converter analysis and modeling
    • Synchronous rectifiers for efficient low d.c. output voltage power conversion
    • Voltage regulator modules for high performance computing applications
    • Fast dynamic boost / buck-boost power converters

      AC to DC power converters for improved power quality

    • Efficient single phase power factor correction schemes for computer and other power supplies
    • High performance three phase pulse-width modulated power converters and their control
    • Conducted EMI noise and mitigation in a.c. to d.c. power converters


      High-performance stand-alone and grid-connected inverters for renewable energy and other applications

    • Fast response control of inverter with excellent output voltage quality under linear and non-linear loads
    • Novel PWM techniques to solve the time delay problem in inverters for obtaining greater output voltage
    • Resonant power conversion schemes for grid connected fuel cell systems
    • Topologies and control schemes for single-stage ac modules for solar photovoltaic systems


    Several of these power electronics related topics are also very relevant in electrical systems for renewable energy applications including solar photovoltaic systems. Developing economical schemes capable of excellent performance in terms of efficiency, life and control performance will continue to be a major challenge in the introduction and acceptance of renewable electric energy systems.

    Lastly, as we are all aware, mankind's addiction to cheap and convenient energy sources and carriers has created a global crisis which only promises to worsen with time. The problems as well as the possible mitigations and solutions straddle numerous disciplines, such as, science, engineering (including the field of power electronics), economics and policy. People with different domain expertise have opportunities to collaborate and contribute in this critical area.

Supervision of Research Students

Ph. D Degree
  • Li Yanlin: Topology Studies and Control of Microinverters for Photovoltaic Application (Thesis submitted in January 2013)
  • Krishna Mainali: Analysis and Mitigation of Conducted EMI in Switched-Mode Power Supplies
  • Yin Bo: High Performance Control of a Three-phase PWM Rectifier
  • Xu Xinyu: A soft-switch back-to-back bi-directional DC-DC converter and the FPGA based digital control design (2nd supervisor)
  • Deng Heng: High Performance Digital Control of UPS Inverters
  • K. Viswanathan: Dynamic performance improvement in boost and buck-boost-derived power electronic converters
  • Ramesh Srinivasan: Single Phase Power Factor Correction Investigation and Development of Advanced Techniques
M. Eng Degree (by Research)
  • 18 students have been supervised so far.

Publications

Publications in Journals
  • Li, Y and R Oruganti, "A Low Cost Flyback CCM Inverter for AC Module Application". IEEE TRANSACTIONS ON POWER ELECTRONICS, March 2012: 1295-1303.
  • Rathore, A, A.K.S. Bhat and R Oruganti, "Analysis, Design and Experimental Results of Wide Range ZVS Active-Clamped L-L Type Current-Fed DC/DC Converter for Fuel Cells to Utility Interface". IEEE Transactions on Industrial Electronics, Jan 2012.
  • Krishna, M and R Oruganti, "Conducted EMI Mitigation Techniques for Switch Mode Power Converters - A Survey". IEEE TRANSACTIONS ON POWER ELECTRONICS, 25, no. 9 (2010): 2344-2356.
  • Li, Y and R Oruganti, "A flyback-CCM inverter scheme for photovoltaic AC module application". Australasian Journal of Electrical & Electronic Engineering, 6, no. 3 (2009).
  • Yin, B, R Oruganti, S K Panda and AKS Bhat, "A simple single input single output (SISO) model for a three-phase PWM rectifier". IEEE TRANSACTIONS ON POWER ELECTRONICS, 24, no. 3 (2009): 620-631.
  • Deng, H, D Srinivasan and R Oruganti, "B-spline Network Based Neural Controller for Power Electronics Application". NEUROCOMPUTING, (2009). (Netherlands).
  • Rathore, A, A.K.S. Bhat and R Oruganti, "A comparison of soft-switched DC-DC converters for fuel cell to utility interface application". IEEJ Transactions on Industry Applications, 128, no. 4 (2008). (Japan).
  • Yin, B, R Oruganti, S K Panda and AKS Bhat, "An output power control strategy for a three-phase PWM rectifier under unbalanced conditions". IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, 55, no. 5 (2008): 2140-2151.
  • Deng, H, R Oruganti and D Srinivasan, "Neural Controller for UPS Inverters Based on B-Spline Network". IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, 55, no. 2 (2008): 899-909.
  • Deng, H, R Oruganti and D Srinivasan, "A Simple Control Method for High Performance UPS Inverters through Output Impedance Reduction". IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, 55, no. 2 (2008): 888-898.
  • Deng, H, R Oruganti and D Srinivasan, "High performance control of UPS inverters using a B-spline network". IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, March, 2008.
  • Krishna, M, R Oruganti, V Kanakasabai and SP Ng, "A metric for evaluating the EMI spectra of power converters". IEEE TRANSACTIONS ON POWER ELECTRONICS, 23, no. (2008): 2075-2081.
  • Viswanathan, K and R Oruganti, "Evaluation of power losses in a boost PFC unit by temperature measurements". IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, 43, no. 5 (2007): 1320-1328.
  • Deng, H, R Oruganti and D Srinivasan, "Analysis and Design of Iterative Learning Control Strategies for UPS Inverters". IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, 54, no. 3 (2007): 1739-1751.
  • Xu, Xinyu, A M Khambadkone, M L Toh and R Oruganti, "A 1MHz Zero-Voltage-Switching Asymmetrical Half-Bridge DC-DC Converter: Analysis and Design.". IEEE TRANSACTIONS ON POWER ELECTRONICS, 21, no. 1 (2006): 105-113.
  • Viswanathan, K, R Oruganti and D Srinivasan, "Dual Mode Control of Cascade Buck-boost PFC Converter". IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, 2006.
  • Viswanathan, K, R Oruganti and D Srinivasan, "Non-linear function controller: A simple alternative to fuzzy logic controller for a power electronic converter". IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, 52, no. 5 (2005): 1439-1448.
  • Viswanathan, K, R Oruganti and D Srinivasan, "Dual mode control of tri-state boost converter for improved performance". IEEE TRANSACTIONS ON POWER ELECTRONICS, 20, no. 4 (2005): 790-795.
  • Deng, H, R Oruganti and D Srinivasan, "PWM methods to handle time delay in digital control of UPS inverters". IEEE Power Electronics Letters, 3, no. 1 (2005): 1-6.
  • Viswanathan, K,R Oruganti and D Srinivasan, "A novel tri-state boost converter with fast dynamics". IEEE TRANSACTIONS ON POWER ELECTRONICS, 17, no. 5 (2002): 677-683.
  • Oruganti, R and M Palaniapan, "Extension of Inductor Voltage Control to Three Phase Buck Type Converter". IEEE TRANSACTIONS ON POWER ELECTRONICS, 15, no. 2 (2000): 295-302.
  • Oruganti, R and M Palaniapan, "Inductor Voltage Control of Buck Type Single Phase AC-DC Converter". IEEE TRANSACTIONS ON POWER ELECTRONICS, 15, no. 2 (2000): 411-417.
  • Pan, H, Y C Liang and R Oruganti, "Design of Smart Power Synchronous Rectifier". IEEE TRANSACTIONS ON POWER ELECTRONICS, 14, no. 2 (1999): 308-315.
  • Mi, N L, R Oruganti and S X Chen, "Modelling of Hysterisis effects in Ferrite Cores excited by Transient Magnetic Field". IEEE TRANSACTIONS ON MAGNETICS, 34, no. 4 (1998):
  • Srinivasan, R and R Oruganti, "A unity power factor converter using half bridge boost topology". IEEE TRANSACTIONS ON POWER ELECTRONICS, 13, no. 3 (1998): 487-500.
  • Oruganti, R , K Nagaswami and K S Lock, "Predicted (on-time) equal charge criterion scheme for constant frequency control of single phase boost type AC-DC converters". IEEE TRANSACTIONS ON POWER ELECTRONICS, 13, no. 1 (1998): 47-57.
  • Oruganti, R , C H Phua, K G Tan and A C Liew, "Soft-switched DC/DC converter with PWM control". IEEE TRANSACTIONS ON POWER ELECTRONICS, 13, no. 1 (1998): 102-114.
  • Oruganti, R and R Srinivasan, "Single Phase Power Factor converters - A Review". SADHANA-ACADEMY PROCEEDINGS IN ENGINEERING SCIENCES, 22, no. 6. 1997: 753-780.
  • Oruganti, R , "Trends in power electronics". IES JOURNAL, 37, no. 6 (1997): 15-23. (Singapore).
  • Srinivasan, R and R Oruganti, "A single phase parallel power processing scheme with power factor control". INTERNATIONAL JOURNAL OF ELECTRONICS, 80, no. 2 (1996): 291-306.
  • Seah, C E, R Oruganti and Y C Liang, "An automated algorithm for small signal analysis of DC-DC converters". IEEE TRANSACTIONS ON POWER ELECTRONICS, 11, no. 1 (1996): 45-52.
  • Liang, Y C, R Oruganti and T B Oh, "Design optimisation of power MOSFET for high frequency synchronous rectification". IEEE TRANSACTIONS ON POWER ELECTRONICS, 10, no. 3 (1995): 388-395.
  • Oruganti, R and C H Tan, "Resonant-tank control of parallel resonant converter". IEEE TRANSACTIONS ON POWER ELECTRONICS, PE-8, no. 2 (1993): 127-134.
  • Oruganti, R and Y T Cham, "Power factor correction techniques in off-line switching power supplies". IES Journal, 33, no. 1 (1993): 27-35. (Singapore).
  • Oruganti, R , J J Yang and F C Lee, "Implementation of optimal trajectory control of series resonant converter". IEEE TRANSACTIONS ON POWER ELECTRONICS, PE-3, no. 3 (1988): 318-327.
  • Tsai, F S, R Oruganti and F C Lee, "A novel control for bidirectional power flow of a parallel resonant converter". IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, IA-23, no. 5 (1987): 937-443.
  • Jovanovic, M M, K H Liu, R Oruganti and F C Lee, "State plane analysis of quasi-resonant converters". IEEE TRANSACTIONS ON POWER ELECTRONICS, PE-2, no. 1 (1987): 36-44.
  • Liu, K H, R Oruganti and F C Lee, "Quasi-resonant converters - Topologies and characteristics". IEEE TRANSACTIONS ON POWER ELECTRONICS, PE-2, no. 1 (1987): 62-71.
  • Oruganti, R and F C Lee, "Resonant power processors, part II- Methods of control". IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, IA-21, no. 6 (1985): 1461-1471.
  • Oruganti, R and F C Lee, "Resonant power processors, part I- State plane analysis". IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, IA-21, no. 6 (1985): 1453-1460.
  • Oruganti, R and A Bhandari, "Characteristics of semiconductor fuses for SCR protection". Journal of the Institute of Electrical and Tele. Comm EngRs., India, 29, no. 2 (1983): 77-82. (India).
Selected Conference Papers
  • Rathore, A. K. S. Bhat, and R Oruganti, "High-frequency current-fed fuel cell inverter for residential use," IEEE Power Electronics, Drives and Energy System (PEDES) Conference. New Delhi, India, 21-23 Dec 2010.
  • Li Yanlin, R Oruganti, "A Flyback-CCM Inverter Scheme for Photovoltaic AC Module Application". Proceedings of the Australasian Universities Power Engineering Programme, AUPEC-08, Sydney, Dec 2008.
  • R Oruganti R Orugantirnational Conference on Energy Technologies and Policy. 7-10 Sep 2008, University of Birmingham, United Kingdom.
  • Krishna, M and R Oruganti, "Design of a Current-Sense Voltage-Feedback Common Mode EMI Filter for an Off-line Power Converter". Proceedings of the IEEE 39th Power Electronics Specialists Conference (PESC 2008). 15 - 19 Jun 2008, Rhodes, Greece.
  • Xu, Xinyu, A M Khambadkone and R Oruganti, " A Soft-Switched Back-to-Back Bi-directional DC/DC Converter with a FPGA based Digital Control for Automotive applications". Proceedings of Industrial Electronics Society, 2007. IECON 2007. 33rd Annual Conference of the IEEE (2007). United States: IEEE. 5 - 8 Nov 2007, Taipei, Taiwan.
  • Mainali, K and R Oruganti, "Simple analytical models to predict EMI noise in a power electronic converter". Proceedings of Industrial Electronics Society, 2007. IECON 2007. 33rd Annual Conference of the IEEE (2007). United States: IEEE. 5 - 8 Nov 2007, Taipei, Taiwan.
  • Rathore, A K, A K S Bhat and R Oruganti, "A Comparison of Soft-Switched DC-DC Converters for Fuel Cell to Utility Interface Application". Proceedings of the Power Conversion Conference, PCC '07 (2007): 588-594. 2 - 5 Apr 2007, Nagoya, Japan.
  • Marecar, H and R Oruganti, "Fast and Accurate Current Sensing in a Multiphase Buck Converter". Proceedings of IEEE Power Electronics and Drive Systems Conference (2005). IEEE. 28 Nov - 1 Dec 2005, Kuala Lumpur.
  • Deng, H, R Oruganti and D Srinivasan, "Modeling and Control of Single Phase UPS Inverters: A Survey". Proceedings of IEEE Power Electronics and Drive Systems Conference (2005). IEEE. 28 Nov - 1 Dec 2005, Kuala Lumpur.
  • Cao, X and R Oruganti, "Fast Response Control of Stepping Inductance Voltage Regulator Module". IEEE Power Electronics Specialists Conference (2005).
  • Viswanathan, K, R Oruganti and D Srinivasan, "Dual-mode control of buck-boost PFC converter". IEEE Power Electronics Specialists Conference Record (PESC 2004): 2178-2184. 20 - 25 Jun 2004, Aachen, Germany.
  • Srinivasan, R, M Palaniapan and R Oruganti, "A single phase two-switch buck type AC-DC converter topology with inductor voltage control". IEEE power electronics specialists conference record '97 (PESC '97) (1997): 556-563. USA: IEEE. 1 Jun 1997, St Louis, USA.
  • Li, X and R Oruganti, "A soft-switching PWM converter with synchronous rectification". Proceedings of IEEE International Telecommunications Energy Conference '96 (INTELEC'96) (1 Oct 1996, United States).
  • Dubey, G K, R Oruganti, C S Chang and K Chatterjee, "Harmonic elimination in high power GTO converter using an auxiliary converter with zero fundamental power". 1996 International Conference on Power Electronics, Drives and Energy Systems for Industrial Growth (1996): New Delhi: Institute of Electrical and Electrical Engineers. 1 Jan 1996, India.
  • Seah, C E and R Oruganti, "Large signal and steady state analyses of DC-DC power converters". International Conference on Power Electronics and Drive Systems (1995). Singapore: IEEE Singapore Section. 21 - 24 Feb 1995, Singapore.
  • Oruganti, R and Y T Cham, "A novel PFC scheme for AC to DC converter with reduced losses". IEEE Industrial Electronics Conference Record (1994). 5 - 9 Sep 1994, Bologna, Italy.
  • Phua, C H and R Oruganti, "Family of two-switch soft-switched asymmetrical PWM DC/DC converters". IEEE Power Electronics Specialists Conference Record (1994): 85-94. 21 - 24 Jun 1994, Taipei, Taiwan.
  • Liang, Y C, T B Oh and R Oruganti, "Design optimisation of power MOSFET for high frequency synchronous rectification". IEEE IECON'93 (1993): 767-772. 15 - 19 Nov 1993, Hawaii, United States.
  • Oruganti, R, K M Chua and K S Lock, "Power conversion using a rotating field transformer". Proceedings of the 3rd international symposium on electricity distribution and energy management (ISEDEM '93) (1993). Singapore: IEEE Singapore. 27 - 29 Oct 1993.
  • Oruganti, Rand F C Lee, "Effects of parasitic losses on the performance of series resonant converter". IEEE-IAS-1985 Annual Meeting, Conference Rec. (1985): 1233-1243.
  • Oruganti, Rand F C Lee, "State plane analysis of parallel resonant converter". IEEE Power Electronics Specialists Conference Rec. (1985): 56-73.
  • Oruganti, R and F C Lee, "Resonant power processors, part II- Methods of control". IEEE-IAS-1984 Annual Meeting, Conference Rec. (1984): 868-878.
  • Oruganti, R and F C Lee, "Resonant power processors, part I - State plane analysis". IEEE-IAS-1984 Annual Meeting, Conference Rec. (1984): 860- 867.

Research Funding

As the Principal Investigator or as the Major Contributor:
  • "Improving the Performance of Active Power Factor Correction Scheme" Funded by M/s. Nemic Lambda (S) Pte Ltd - 2005~2007. Funding S$180000.
  • "Dynamic Voltage Restorer System for Power Quality Improvement" University Research Project - 2000~2003. Funding S$50600.
  • "Power Quality Improvement Using Artificial Intelligence Techniques" University Research Project - 2001~2004. Funding S$73786.
  • "Three Phase AC-DC Converters for Improved Power Quality" University Research Project - 2001~2006. Funding S$68100. Collaboration with University of Victoria.
  • "New Generation Power Supply Development" together with M/s. Nemic Lambda (S) Pte Ltd - 1991~1994. Funded by the National Science and Technology Board. The research has resulted in a patent and also an advanced DC-DC converter module being introduced by Nemic Lambda in their product range.
As Collaborator
  • "Universal Power Electronic Cell" University Research Project - 2000~2004. Funding S$68600. Collaborator.
  • "Neural Network Tooled Power Electronic Design Automation" University Research Project - 1991~1993. Funding S$72000. Collaborator.

Research Accomplishments

  • First Prize paper - IEEE Transactions on Power Electronics in 2000 for the year 1999 (with Liang, YC & Pan, H).
  • Invited paper (with Srinivasan, R) in the "Special Issue on Recent Advances in Power Electronics and Drives", Sadhana, Indian Academy of Sciences, December 1997.
  • A conference paper (with Phua, CH) included in the IEEE Press Book, "Power Electronics Technology and Applications", 1996.
  • A conference paper (with Lee, FC) included in the IEEE Press Book, "Modern Power Electronics", 1992.
  • Two conference papers (Part I & Part II) (with Lee, FC) together were awarded the first prize of the Static Power Converter Committee at the IEEE-IAS-1984 annual meeting.
  • Fast response 'Optimal Trajectory Control' method proposed for a series resonant power converter has been adopted by GE-Medical (and possibly by other medical imaging equipment manufacturers) for controlling power in their Magnetic Resonance Imaging (MRI) equipment.
  • Patent: R Oruganti, CH Phua and J Tan, "DC-DC Converter", Japanese Patent: 2751961 (1998). This is still used by the company in one of its DC-DC converter product line.

Teaching

The courses developed and taught at NUS include
  • EE3501/TE3501 Power Electronics.
  • EE5711 Power Electronics and Systems.
  • EE6002 Switch Mode Power Conversion.
  • EE4510 Solar Photovoltaic Energy Systems.
  • EG2401 Engineering Professionalism.
Teaching Honours
  • In the Faculty Teaching Honours list for 1998/99.
  • A Faculty of Engineering nominee for the University's Outstanding Educator award in 2001.
  • In the Department's Teaching Commendation List during (2002-03) and (2003-04).

Service

At the University
  • Director, Centre for Power Electronics (1994 - 2008).
  • Chairman of the working committee for the 'Engineering Professionalism' module (2003-04).
  • Deputy Group Head of Drives, Power and Control Systems Group and Section Head of Drives & Power (2002-2007).
  • Graduate Programme Coordinator (2009-10).
  • Member, Purchase Authorisation Committee.
  • Member, Curriculum Task Force committee .
  • Supervisor, Power Electronics Laboratory (1995-2003).
Professional
  • Was instrumental in starting the series of IEEE Power Electronics and Drive Systems (PEDS) Conferences together with other interested professionals in Singapore. Was the Organizing Chairman for the first PEDS'95 in Singapore. After the second PEDS conference, also in Singapore, a PEDS Management Committee was set up in Singapore under the IEEE Singapore Section in order to promote and manage the IEEE-PEDS conferences in the region. This conference is now an important Power Electronics Conference in IEEE's annual calendar.
  • Invited member of Program Committee (Power Electronics) of the 2003 IEEE Industrial Electronics Society Annual Conference (IECON'03) and other conferences.
  • Invited Organizing Committee member of the 2002 IEEE Power Electronics Specialists Conference (PESC'02) Co-associate editor of the IEEE Press Book, "1996 Power Electronics Technology and Applications" under the IEEE Technology Update Series.
  • Technical Committee Member for the 1994 and 1996 IEEE Power Electronics Specialists Conferences.
  • Member of the EV panel set up by the National Science and Technology Board in 1994.
  • Chairman, Power Electronics Study Panel set up by NSTB / 1994-95.
  • Short courses: 1) Switch-Mode Power Conversion & 2) Solar Photovoltaic Energy Systems .

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