Keynote Speech 1
Multilevel Power Electronics for Electric Transportation Systems
Multilevel power electronics offer improved efficiency, better power quality, reduced electromagnetic interference (EMI), increased fault tolerance, higher power density, reliability, higher voltage blocking capability, and modularity and scalability in design compared to conventional two-level inverters. Multilevel inverters can be used to drive electric motors in heavy duty electric transportation such as buses, trucks, ships, trains, and aircrafts while maintaining high efficiency and low distortion even at low device switching frequency. Multilevel converters can also be used in ultra-fast DC charging, and power supply systems of railway, aircraft, and ships. Multilevel power electronics will efficiently support the upcoming transition to >800 V (up to medium voltage in future) in all kinds of electric transportation. This talk will focus on optimal pulse width modulation (PWM) switching strategy for the NPC and MMC based multilevel inverters for the electric transportation drive systems. Optimal PWM allows the semiconductor devices to be controlled at extremely low switching frequency (50 Hz to 100 Hz) to limit the switching losses while maximizing the efficiency without compromising in harmonic distortion and power quality. Knowing the stringent requirements of various multilevel power electronics circuit configurations, the PWM strategy can balance input capacitor voltage as well as eliminate common mode voltage.
Biography
Akshay Kumar Rathore is an IEEE Fellow and expert in power electronics and control of electric motor drives. He is currently a Professor in the Department of Electrical and Computer Engineering, National University of Singapore, Singapore. From March 2016-Dec 2021, he served as an Associate Professor at the Department of Electrical and Computer Engineering, Concordia University, Montreal, Canada where he was listed in the Provost Circle of Distinction in 2021. He served as Graduate Program Director and Chair of Graduate Awards during 2020-21. From Jan 2022 to June 2025, he served as a Professor and Programme Leader (Electrical Power Engineering) at Singapore Institute of Technology, Singapore.
Prof. Rathore received the Gold Medal for securing the highest academic standing in his Master’s degree among all electrical engineering specializations at Indian Institute of Technology (BHU) Varanasi, India in 2003. He received his PhD degree in Power Electronics from the University of Victoria, British Columbia, Canada in 2008. He had two subsequent postdoctoral research appointments with the University of Wuppertal, Germany (2008-2009), and the University of Illinois at Chicago, USA (2009-2010).
Prof. Rathore is a recipient of the 2013 IEEE IAS Andrew W. Smith Outstanding Young Member Achievement Award, 2014 Isao Takahashi Power Electronics Award, 2017 IEEE IES David Irwin Early Career Award, 2019 IES Publications Service Recognition Award, 2020 IEEE IAS Outstanding Area Chair Award, 2020 IEEE Bimal Bose Award for Industrial Electronics Applications in Energy Systems, 2021 Nagamori Award, and 2023 Distinguished Alumna Award (Young Achiever)-IIT (BHU), Varanasi, India. He published over 300 research papers in international journals and conferences, including 110 IEEE TRANSACTIONS. He has one approved EU patent on Optimal Pulse width Modulation of Multilevel Inverters that is licensed to WEG, Brazil. His foundational work on the world’s first Snubberless Current -fed DC/DC Converters and fundamental device switching frequency control of Medium Voltage Multilevel Inverters for high power industrial drives is widely accepted and referred.
Prof. Rathore is currently serving as the Chair of the IEEE IAS Andrew W Smith Outstanding Young Member Achievement Award Committee, co-Editor-in-Chief of IEEE Transactions on Industrial Electronics, IEEE Fellow Evaluation Committee member of Industrial Electronics Society, member of the IEEE Nikola Tesla Award Committee, IEEE Medal in Power Engineering Committee, and a Distinguished Lecturer of the Power Electronics Society. Since 2017, he has been serving on the Executive Board of the IEEE Industry Applications Society in various roles of Member-at-Large, Awards Department Chair, and MSDAD Chair. He has been an AdCom member of the IEEE Industrial Electronics Society since 2021. He has Chaired IEEE IAS Renewable and Sustainable Energy Conversion Systems Committee (2022-2023), IEEE IAS Industrial Automation and Control Committee (2018-19) and IEEE IAS Technical Committee on Transportation Electrification (2016-17).