Research

Oct 2013 – Oct 2018: University of Cambridge (UK), Department of Engineering , Churchill College

Doctoral Researcher in Electrical Engineering; Specialization: Power Electronics

PhD Thesis: ‘Gallium Nitride (GaN) Power Electronics using Machine Learning (ML)’

The aim of this research work is to bridge the gap between laboratory research and real-world applications/commercialization of GaN. I successfully developed a ML based universal GaN power device and circuit model. Through this contribution, designers will be able to better understand and work with these novel devices with relative ease. This will aid the need for faster adoption of GaN devices by the industry removing some the barriers to commercialization. Finally, the findings of this work have been generalized to frame machine learning based techniques to address the need for generic modelling of power electronic devices. These solutions are presented as an information manual to researchers, engineers and students interested in benefiting from adopting machine learning for power electronics applications. To read more, visit: https://doi.org/10.17863/CAM.35893

  • Self-designed and directed PhD, established collaborations with ML experts from MIT, UCSD & Oxford University; supervised 3 electrical engineering undergrad students from SRM University, India.
  • Independently established collaboration with GaN companies: GaN Systems, Panasonic, Sanken & EPC 
  • 15 first author, 3 second author and 2 third author peer reviewed publications; 3 under review
  • 14 invited talks: 4 invited keynotes and 10 technical talks in international conferences and workshops
  • Technical skills developed: ML, LT-Spice, PSpice, Altium, Power electronic circuit design and PCB design

Scholarships & Prizes for research

2013-17:  Cambridge University Nehru Trust Scholarship

2018:  Commendation for Research at the EPSRC Future Power Challenge

2017-18: Google Europe Scholarship

2017-18: Department of Engineering Research Grant, IET Travel Award

2016-17:  FfWG Foundation Main Research Grant

2016-17:  Churchill College Copisarow Grant Fund

2015-16:  Department of Engineering W G Collins Endowment Conference Fund

2015-16:  IET Connect Lord Hirst Fund

2016-17:  Best Research Talk Award at the EPSRC Centre for Power Electronics Summer School’16, UK

2015-16:  Best Poster Presentation Award at the Annual Power Electronics Conference’15, UK

List of Selected Publications

First author papers:

  1. N. Hari, M. Ahsan, S. Ramasamy, P. Sanjeevikumar, A. Albarbar and F. Blaabjerg, “Gallium Nitride Power Electronic Devices Modelling using Machine Learning,” in IEEE Access, vol. 8, pp. 119654-119667, 2020
  2. Nikita Hari, Edward Shelton, Teng Long, “Investigation of Gate Drive Strategies for High Voltage GaN HEMTs” in Energy Procedia, Elsevier, Vol 117, June 2017,1152-1159
  3. N. Hari, S. Chatterjee and A. Iyer, “Gallium Nitride Power Device Modeling using Deep Feed Forward Neural Networks,” 2018 1st Workshop on Wide Bandgap Power Devices and Applications in Asia (WiPDA Asia), Xi’an, China, 2018, pp. 164-168
  4. Nikita Hari, Tom Logan, Richard McMahon, “Design Considerations for 600 V GaN HEMT based Half -Bridge Converter Systems for Utility Based Applications”- Proceedings of the 8th International Conference on Power
    Electronics, Machines and Drives, IET- PEMD-2016, Glasgow, April 19-22, 2016, PP.6-7
  5. Nikita Hari, Edward Shelton, Teng Long, “Investigation of Gate Drive Control for High Voltage GaN HEMTs”- Proceedings of the International Conference on Power Engineering, Computing and Control, PECCON-2017,2-4 March 2017, VIT, Chennai, PP 10-15
  6. Nikita Hari, Tom Logan, Florin Udrea, Vaithilingam Chidambaram “Investigation of Instabilities in GaN Based Power Circuits”- Invited paper for the Proceedings of the fifth International Conference on AI in Engineering System & Power Circuit and Information Technologies (ICPCIT2016), Chennai, India, May19-21, 2016, PP 100-104
  7. Nikita Hari, Florin Udrea, “Investigation of Parasitics in Power Circuits Switched with Cascode GaN HEMTs” in International Journal of Research in Engineering Technology – March 10,2016, PP 1-7
  8. Nikita Hari, Florin Udrea “Investigation of Parasitics in Power Circuits Switched with GaN-HEMTs”-Invited paper for the Proceedings of the International Conference on Signal, Power, Communication, Security, and Computing Applications- (ICSPCSCA), Oct 19-21,2016, PP 29-31
  9. Nikita Hari “GaN Power Electronic Solutions for Efficient Wireless Power Transfer” Invited paper at 3rd International Conference and Business Expo on Wireless & Telecommunication, July 20-21, 2017 Munich, Germany
  10. Nikita Hari, ” GaN Power Electronic Solutions for Efficient Wireless Power Transfer”, International Journal of Sensor Networks and Data Communications, July 21, Vol.6, Issue 1, PP 67
  11. Nikita Hari, Vijayakumar, Subranshu Dash, ” A Novel Control Strategy for Performance Enhancement of Unified Power Quality Conditioner”, Proceedings of International Review of Automatic Control (Theory and Applications) – November 2012 (Vol. 5, N. 6)
  12. Nikita Hari, Vijayakumar, Subranshu Dash, “A Versatile Control Scheme for UPQC for PQ Improvement.” Proceedings of ICETECT-2011(IEEE); ISBN:978-14244-7924-5
  13. Nikita Hari, K.Vijayakumar, “A Simplified Control Scheme for D-Statcom for PQ Improvement”, Proceedings Of The 7th National Control Instrumentation System Conference, CISCON- 2010,
    Manipal, Nov.12-13,2010, Vol. 1, PP. 87-90
  14. Nikita Hari, Vaithilingam Chidambaram, Subranshu Dash, ” An AI based Control Strategy for Unified Power Quality Conditioner”, Proceedings of International Conference on Swarm & Evolutionary Computing, Chennai-2010, Dec 16-19, pp 100-102
    Second /Third/Fourth author papers:
  15. Edward Shelton, Nikita Hari, Patrick Palmer “Design and Measurement Considerations for Wide Band Gap Device Based Switching Circuits”, Accepted for 19th European Conference on Power Electronics and Applications (EPE), 11- 14 September 2017, Warsaw, Poland
  16. Pathy, Ramasamy Sridhar, Nikita Hari, Subhranshu Dash and Subramani, “A modified module integrated – Interleaved boost converter for standalone photovoltaic (PV) application,” 2016 IEEE International Conference on Renewable Energy Research and Applications (ICRERA), Birmingham, 2016, pp. 989-994
  17. Edward Shelton, Xueqiang Zhang, Tianqi Zhang, Nikita Hari and Patrick Palmer, “Low Inductance Switching for SiC MOSFET Based Power Circuit”- Accepted for IEEE-ECCE, Oct 1-5, 2017, Ohio
    *Accepted for publication:
  18. Pathy, Ramasamy Sridhar, Nikita Hari, Subhranshu Dash and Subramani, “A modified module integrated interleaved boost converter for standalone photovoltaic (PV) application”-selected for publication in International Journal of Renewable Energy Research, IJRER
  19. C. Balaji, S. S. Dash, N. Hari and P. C. Babu, “A four port non-isolated multi input single output DC-DC converter fed induction motor,” 2017 IEEE 6th International Conference on Renewable Energy Research and Applications (ICRERA), San Diego, CA, 2017, pp. 631-637
    *In Review /Submission/Preparation:
  20. Nikita Hari et al, “Parasitic Extraction and Behavioral Modelling of GaN Power Devices”; In Preparation for IEEE Transactions on Power Electronics: Review
  21. Nikita Hari et al, “Modelling of GaN Power Circuits using Deep Feed Forward Neural Networks”: In Preparation for IET Power Electronics: Expected to be submitted by Dec 2020
  22. Nikita Hari, Saurabh Chandra and Sridhar Ramasamy “Modelling of Gallium Nitride Power Devices Using Machine Learning “; Submission for Nature-Scientific Reports: In preparation
  23. Nikita Hari, Saurabh Chandra, “Modelling of Power Electronic Devices and Circuits Using Machine Learning”: Preparation for IEEE letters: In preparation