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The Pilawa Group is proud to celebrate the graduation of Sahana Krishnan, Rod Bayliss III, and Francesca Giardine, who have each earned their Doctor of Philosophy degree in Electrical Engineering and Computer Sciences from UC Berkeley.

Advised by Professor Robert Pilawa-Podgurski, all three researchers made significant contributions to the field of power electronics and presented impactful dissertation defenses during the Spring 2026 semester.

Sahana Krishnan successfully defended her dissertation, “Power Dense DC-DC Converters for Electric Transportation: Design Optimization and Practical Considerations,” on April 29, 2026. Her research focused on the design and implementation of advanced converter architectures for transportation electrification, addressing practical challenges associated with achieving high power density and efficiency.

Rod Bayliss III defended his dissertation, “Dynamical Modeling and Control Design for the Flying Capacitor Multilevel Converter in High-Density, High-Efficiency AC/DC and DC/AC Applications,” on April 22, 2026. His work advanced the understanding and control of flying capacitor multilevel converters for next-generation high-performance power conversion systems.

Francesca Giardine defended their dissertation, “Analysis and Operation of Flying Capacitor Multilevel Converters: Single-Phase Applications and Fundamental EMI Scaling,” on April 24, 2026. Their research provided new insights into the operation of flying capacitor multilevel converters and the scaling of electromagnetic interference in these systems.

Throughout their time at Berkeley, Sahana, Rod, and Francesca were valued members of both the Pilawa Group and the broader BPEC community, contributing not only through their research accomplishments but also through mentorship, collaboration, and service to fellow students.

Following graduation, Sahana will join Rivian & Volkswagen Group Technologies, Rod will join NVIDIA, and Francesca will continue advancing their research as a postdoctoral scholar in the Pilawa Group.

We congratulate Sahana, Rod, and Francesca on this important milestone and look forward to their continued contributions to the fields of power electronics and energy conversion.

Graduate student Emmi Wyttenbach was recently awarded the 2026 Tong Leong Lim Pre-Doctoral Prize in the Electrical Engineering and Computer Science Department! This annual prize is awarded to EECS graduate students who achieve the highest scores in their preliminary examinations. Emmi is the first Pilawa Group member to receive this prize. Her current research spans the modeling and control of resonant switched capacitor converters and the generation of very high frequency electromagnetic waves for MRI applications. The award details can be found here: https://www2.eecs.berkeley.edu/Students/Awards/

BPEC Boles Group members Ben Karish, Wentao Xu, and Sourav Naval were also awarded–details can be found here: https://bpec.berkeley.edu/?p=1200

Graduate students Rod Bayliss III, Emmi Wyttenbach, and Tahmid Mahbub were recently recognized with best presentation awards for their work at APEC 2026 at San Antonio, Texas! Their work spans three compelling application spaces of switched capacitor converters. Rod was awarded for his work titled “Design and Implementation of a Three-Phase Eight-Level Flying Capacitor Multilevel Rectifier for Future Data Center Power Delivery,” in which he demonstrates the rectification of a 480V grid to a high voltage, 800V DC bus. This research helps to pave the way for high voltage power delivery in data center applications, and can be read at the following link. Emmi’s work also has important implications for the future of data center power delivery. She was awarded for her work titled “An Output Voltage Maximizer for Efficiency Improvement in Resonant Switched-Capacitor Converters,” in which she presents a control technique to improve the efficiency of resonant switched-capacitor converters, a popular choice for intermediate bus converters. Finally, Tahmid was awarded for his work on the design of an exceptionally gravitationally dense power converter for more-electric aircraft DC bus generation. His work is titled “An 8-level Flying Capacitor Multilevel Boost Converter for High-Voltage Power Distribution in Electric Aircraft” and helps pave a path forward for realizable electric flight in the future.

Congratulations to Tahmid, Emmi, and Rod on their incredible achievements!

Third-year graduate student Tahmid Mahbub was recently recognized in the student demo competition at APEC 2026 in San Antonio, Texas, winning 2nd place overall. His work, titled “A Novel Multi-Kilowatt Thermal Test Vehicle Utilizing Off-the-Shelf Power Transistors,” demonstrates the generation of localized hot spot patterns for the testing of cooling systems, particularly those destined for data center power delivery systems. His related work from the 2025 ECTC conference can be read at the following link.

Congratulations, Tahmid, on this achievement!

BPEC researchers Syed Tahmid Mahbub and Nagesh Patle are recipients of the 2025 Graduate Research Grants from the nonprofit organization Hearts to Humanity Eternal (H2H8). This broadly defined award is granted to thirty graduate researchers each year to fund research that improves world-affecting problems like climate change or furthers advancements in medicine, space exploration, artificial intelligence, and more. Nagesh’s graduate research centers upon ultra-efficient, ultra-dense hybrid switched-capacitor power converters for data center and automotive systems to ease the power delivery limits that constrain modern AI and advanced computing. Tahmid’s graduate research addresses practical challenges in power electronics to help accelerate the adoption of renewable energy and electric transportation, and to reduce power consumption in data centers.

Read Tahmid’s and Nagesh’s features in the H2H8 EECS page here: https://h2h8.com/explorer-categories/electrical-engineering-computer-sciences/

Recent Pilawa Group graduates Dr. Rahul Iyer and current postdoctoral scholar Dr. Yicheng Zhu have each been awarded the 2025 PELS Ph.D. Thesis Talk Award! This award is granted yearly to outstanding graduates who have defended their thesis and submit an additional video submission to the IEEE Power Electronics Society. Participants are judged based on the achieved outcomes of their work in power electronics, the rigor of their design methodology, net contribution to the progress of the field, and quality of presentation. Dr. Iyer and Dr. Zhu are among a total of five worldwide winners for the current academic year.

The Berkeley Power and Energy Center’s very own Professor Jessica Boles was a past recipient of this award in 2023. Pilawa Group alumnus Dr. Zichao Ye was a past recipient of this award in 2021.

Read more about the 2025 winners–and past winners–of the award here: https://www.ieee-pels.org/awards/pels-ph-d-thesis-talk-p3-talk/

The Pilawa Research Group is very pleased to introduce our 2025 cohort! Harry Choi and Khalid Durani come from strong research backgrounds in their respective fields, and we are delighted to see what problems they tackle over the course of their graduate careers. Please see their bios below:

Seokwon (Harry) Choi received his B.S. degree in Electrical and Computer Engineering from Seoul National University, South Korea, in 2025. Before joining BPEC, he was a graduate student researcher in the Electric Energy Conversion Lab at Seoul National University. His research interests include the design and control of switched-capacitor converters and high-frequency power conversion. Harry is a recipient of the Berkeley Fellowship and the KFAS Overseas PhD Scholarship.

Khalid Durani received his B.S. degree in Electrical Engineering and Computer Science from the University of California, Berkeley in December 2023. His research interests include the dynamic modeling and control of power converters.

Once again, a very warm welcome to our new students!

Graduate student Sahana Krishnan has won a Best Poster Award at the 2025 IEEE Transportation Electrification Conference and Expo & Electric Aircrat Technologies Symposium (ITEC) for her work “Design and Implementation of a GaN-Based, Cascaded Isolated DC-DC Converter for Satellite Applications.” Sahana’s innovative research, completed with coauthors Francesca Giardine and Rose Abramson, validates a 150 W, 92% efficient cascaded boost and dual-active bridge power stage for lightweight CubeSat and SmallSat satellite systems, demonstrating the utility of this topology in the extreme environment of space. Sahana’s presentation was one of just three winning selections out of more than 200 posters presented at ITEC 2025.

This work can be read at the following link: https://doi.org/10.1109/ITEC63604.2025.11097988

Graduate student Nagesh Patle received the 2025 Timothy B. Campbell Innovation Award, which is granted once per year to a computer science or electrical engineering graduate student who demonstrates a spirit of innovation, collaboration, and creativity in their work and method. The award honors the memory of Timothy B. Campbell, a former Ph.D. student working on digital fabrication and the human-computer interface at UC Berkeley, before he passed away from cancer in 2015. As part of receiving this award, Nagesh met with the Campbell family to learn more about Timothy’s work, life, and impact. You can watch Nagesh’s acceptance speech in the video below, and read more about the Timothy B. Campbell Innovation Award at this link: http://campbellscholar.org/. Past winners of the award are listed at this page: https://www2.eecs.berkeley.edu/Students/Awards/100/.

Visiting Ph.D student Leheng Wang was recognized for his technical achievements and research in the areas of resonant converters in EV chargers and data center power conversion by the IEEE Power Electronics Society. The IEEE PELS Graduate Studies Fellowships are awarded yearly to visiting scholars whose work aligns closely with the mission of PELS. Leheng Wang is a 4th year student visiting the Pilawa Group from the Kai Sun Group at Tsinghua University in China. Read more here: https://www.ieee-pels.org/announcements/congratulations-to-our-2025-pels-award-winners/ and here: https://www.ieee-pels.org/awards/graduate-studies-fellowship-and-john-g-kassakian-fellowship/. We are ecstatic that Leheng has been able to join us these past few months!

Graduate student Rahul Iyer received his Doctor of Philosophy degree in Electrical Engineering and Computer Sciences on May 24th, 2025. His dissertation was titled “Dynamical Modeling and Control of the Flying Capacitor Multilevel Converter.” Post-graduation, Rahul will begin working at Tesla, Inc. on the Power Electronics Controls for Energy Products team. Congratulations!

Syed Tahmid Mahbub has been named one of the 2025 Paul and Daisy Soros Fellows, a national, merit-based award granted to new Americans pursuing research at the graduate level. He is recognized both for his award-winning research in the Pilawa Group and for his educational contributions to multiple universities in the United States. Tahmid’s research in the Pilawa Group centers around reducing datacenter power consumption and facilitating the adoption of renewable energy and electrified transportation. He has contributed as a teaching assistant both to the power electronics curricula at the University of California, Berkeley and to embedded systems curricula at his undergraduate alma mater, Cornell University. Tahmid also maintains a popular blog to help budding engineers navigate educational resource scarcity. You can read more about Tahmid’s award at this link: https://pdsoros.org/fellows/syed-tahmid-mahbub/

Three researchers from the Pilawa Research Group received prestigious awards for outstanding oral and poster presentations at the 40th IEEE Applied Power Electronics Conference (APEC 2025), held in Atlanta, GA. APEC is the premier conference in power electronics, attracting leading experts worldwide.

Syed Tahmid Mahbub, a second-year EE Ph.D student advised by EECS Professor Robert Pilawa-Podgurski, received the Best Oral Presentation Award for his talk titled “Analysis and Implementation of Minimum-Sensor Capacitor Voltage Estimators for Flying Capacitor Multilevel Converters.”

Nagesh Patle, a third-year EE Ph.D student advised by EECS Professor Robert Pilawa-Podgurski, earned the Best Poster Presentation Award for his work on “Achieving Soft-Charging and Over 20% Input Current Ripple Reduction in a 48-to-6 V Dickson Converter Using 3-Phase Split-Phase Control.”

Yicheng Zhu, a postdoctoral scholar and EECS alumnus, advised by EECS Professor Robert Pilawa-Podgurski, was recognized with the Best Oral Presentation Award for his talk titled “Design-Oriented Modeling and Multi-Objective Optimization of Two-Phase Coupled Inductors in Multiphase PWM Converters.”

The APEC Best Presentation Awards recognize outstanding contributions based on several criteria: the quality and design of presentation slides, the clarity and effectiveness of delivery, and the presenter’s ability to engage with and respond to audience questions.

Rod Bayliss III, a fifth-year PhD student advised by Dr. Robert Pilawa-Podgusrki, won a 2024 Outstanding Graduate Student Instructor Award for his role as a GSI in the inaugural offering of EE 213B, Power Electronics Design, taught by Dr. Jessica Boles. This award honors UC Berkeley GSIs each year for their outstanding work in teaching on the Berkeley campus. The semester before the class was offered, Rod designed and tested a custom buck converter for the class. The students used this board to create their own buck converters, learning practical power converter design and testing skills.

BPEC Director Robert Pilawa-Podgurski was elevated to IEEE fellow in the 2024 class, “For contributions to hybrid switched capacitor power converters”. IEEE Grade of Fellow is conferred by the Board of Directors upon a person with an extraordinary record of accomplishments in any of the IEEE fields of interest. The total number of fellows selected in any one year does not exceed one-tenth of one percent of the total voting Institute membership. Robert received his award at IEEE ECCE in Phoenix this past year. This is a great recognition of the all the hard work by past and present BPEC students!

EECS grad Yicheng Zhu has received a Teaching Effectiveness Award for 2024.

The Graduate Division’s Teaching Effectiveness Award for GSIs honors those who devise solutions to teaching or learning problems they have identified in their classes and write them up in a one-page essay. These essays are published on the GSI Center website for use by instructors.

Zhu’s essay, “Fostering Student Engagement: The Power of Live Class Demonstrations,” emphasizes his approach to enhancing student engagement in large lecture formats. Through the implementation of interactive group activities and targeted feedback mechanisms during the 2023 semester, he successfully created a more inclusive environment that encouraged student participation and fostered a deeper understanding of the material.

Yicheng Zhu is a postdoctoral scholar and Bakar Innovation Fellow advised by Robert Pilawa-Podgurski.

Submitted by nluechin on October 17, 2024

https://eecs.berkeley.edu/news/vivek-bharadwaj-and-yicheng-zhu-receive-teaching-effectiveness-award/

Graduate students Francesca Giardine, Kelly Fernandez (PhD, Fall 2023), along with Dr. Robert Pilawa-Podgurski have won Best Paper Award at IEEE Energy Conversion Conference and Expo – Europe.

They presented A Two-Stage Non-Isolated Hybrid Switched-Capacitor Microinverter Utilizing a Fixed-Ratio Resonant DC-DC Stage with Startup Functionality and Flying Capacitor Multilevel DC-AC Stage. Their work demonstrated a 500W two-stage microinverter solution for residential scale solar that uses exclusively hybrid switched-capacitor converter topologies to convert a 35V DC voltage to a 240V AC voltage. The hardware prototype achieved a competitive power density and efficiency, meeting the growing need for compact solutions for residential-scale renewables.

The paper was presented at ECCE – Europe in Darmstadt, Germany. ECCE brings together academics and industry professionals from around the world to exchange ideas about the energy transition. The best papers were chosen based on the quality of the technical results, paper, and presentation.

Submitted by Sarah Douglas on September 5, 2024

https://bpec.berkeley.edu/pilawa-group-graduate-students-win-best-paper-award-at-ecce-europe/

Rahul K. Iyer, S. Tahmid Mahbub, and Robert C.N. Pilawa-Podgurski have won the Best Student Paper Award at the 2024 IEEE International Communications Energy Conference (INTELEC) for their paper “Quasi- Two-Level Switching for Active Balancing of Flying Capacitor Multilevel Converters Under Light-Load Conditions” (https://ieeexplore.ieee.org/document/10678933/)

Recent work in the Pilawa group has highlighted the design of “active-balancing” controllers to ensure the safe operation of high-performance Flying Capacitor Multilevel (FCML) converters during system transients. This work builds on broader efforts to study the converter dynamics and design stable high-bandwidth controllers. In particular, this work highlights techniques to ensure stable converter operation when the load current is small. Compared to prior work relying on Phase-Shifted Pulse-Width Modulation, the proposed switching scheme enables active balancing at average load currents approaching and equal to zero. The conference paper and oral presentation given at IEEE INTELEC 2024 highlight the proposed switching and control methods and showcase the practical implementation of the controller on industry-standard digital signal processor hardware.

They are continuing to work on additional characterization of the balancing controller at different operating conditions, and aim to apply the proposed technique to demonstrate safe startup of the converter at light-load conditions.

Submitted by Sarah Douglas on October 20, 2024

https://bpec.berkeley.edu/rahul-iyer-and-tahmid-mahbub-win-best-paper-award-at-ieee-intelec-2024/

We are pleased to introduce the newest members of our PhD cohort at the Pilawa Group: Emmi Wyttenbach, Dennis Woo, and Shuyu Zhang.

Emmi Wyttenbach joins us from Cornell University, where she earned her Bachelor’s degree in 2024. During her time at Cornell, she conducted power electronics research under Prof. Khurram Afridi, focusing on the development of active energy buffer solutions. Outside of her academic pursuits, Emmi is an avid soccer player and enjoys running and swimming.

Shuyu Zhang completed her Bachelor’s degree at Huazhong University of Science and Technology (HUST) in China in 2023, followed by Master’s studies at Stanford University before joining Berkeley. With a passion for Anime, comics, and games (ACG), Shuyu has been an active cosplayer at anime conventions since 2016. She also has a keen interest in photography.

Dennis Woo graduated from Stanford with a Bachelor’s degree in 2023 and a Master’s degree in 2024. His research background includes high-frequency power electronics and wide-bandgap semiconductor materials. Outside of work, Dennis enjoys exploring the outdoors,
and he spends his time with photography, soccer, volleyball, and climbing.

We look forward to supporting their growth and contributions to the group and are excited for the perspectives they bring!

Having spent the past four years with UC Berkeley, Dr. Ellis is moving to the University of California Santa Cruz — Baskin School of Engineering. Here his research group will be hosted at UCSC’s Westside Research Park, a stone’s throw from Natural Bridges State Beach.

During his time at UC Berkeley, Dr. Ellis collaborated extensively with BPEC researchers, contributing to the development of high-density power electronics and renewable energy systems. His teaching contributions have also earned him UC Berkeley’s recognition for “teaching effectiveness that greatly exceeds the departmental average”.

The Pilawa-Group would like to wish him the best of luck in his continuing academic career!