News

Graduate students Nagesh Patle and Seokwon Harry Choi received Second Place in the Design Methodology Track of the Student Demo Contest at the 2026 IEEE Energy Conversion Congress and Exposition (ECCE), held in Vancouver, Canada, October 4–8. Conference details

Their demonstration, “Automated Topology Discovery and Hardware-Aware Evaluation of Hybrid Switched-Capacitor Converters for 48-V Intermediate-Bus Applications,” showcased an end-to-end automated framework for exploring power-converter designs.

The framework systematically discovers feasible hybrid switched-capacitor topologies, evaluates their soft-charging capability and resonant operation, and selects commercial components to estimate efficiency and power density. This connects topology exploration with practical component choices, helping designers compare candidate converters against the requirements of a particular application.

The project was advised by Professor Robert Pilawa-Podgurski and supported by the Berkeley Power and Energy Center (BPEC). During the demonstration sessions, the team shared the framework with researchers and industry attendees and discussed its methods and potential applications.

Congratulations, Nagesh and Harry!

Graduate students Nagesh Patle and Khalid Durani received Best Oral Presentation Awards for their respective papers at the 27th IEEE Workshop on Control and Modeling for Power Electronics (COMPEL 2026), held at Downing College in Cambridge, United Kingdom, in July 2026.

Nagesh presented “A Switching-Bus Interleaved Doubler (SID) Converter for Regulated 48-V-to-12-V Applications,” coauthored with Haifah B. Sambo, Shuyu Zhang, and Professor Robert Pilawa-Podgurski. The work addresses a challenge in data center power delivery: maintaining a stable 12 V intermediate supply as the upstream bus voltage varies from 40 to 60 V.

The proposed converter uses a switching-bus architecture to eliminate bulky intermediate passive components. A split-phase timing strategy maintains soft-charging operation while accounting for the reduction in effective capacitance that ceramic capacitors experience under applied voltage. The paper reports an experimentally validated hardware prototype with a peak efficiency of 97.8% and a power density exceeding 6,200 W/in³ at a nominal 48 V input.

Khalid presented “A Multilevel Series-Capacitor Buck Converter with Duty Cycle Extension through Switched Node Voltage Decoupling,” coauthored with Nathan Biesterfeld and Professor Robert Pilawa-Podgurski. The work introduces a new converter topology for efficient, high-ratio voltage conversion in data center power systems. It targets lower intermediate bus voltages, which can improve overall system efficiency and support compact downstream voltage regulators.

The topology addresses a duty-cycle limitation arising from coupling between switched-node voltages in series-capacitor buck converters. By incorporating a pair of decoupling switches, the proposed architecture allows these voltages to operate independently, extending the usable duty-cycle range. A four-level, two-branch hardware prototype demonstrated 48-V-to-4-V conversion, with measured efficiency reaching 95.7% including gate-drive losses.

Nagesh also received a Student Travel Award.

Congratulations to both teams!

Details of the technical sessions are available in the COMPEL 2026 programme.

Graduate student Nagesh Patle received a Best Poster Award in Theme 3 at the 2026 Center for Ubiquitous Connectivity (CUbiC) Annual Review, held at Columbia University in New York on June 24–25.

His poster, “Ultra-Dense, High-Efficiency DC-DC Power Conversion for Connectivity and AI Applications,” presented early work on compact, efficient power delivery for computing and communication systems. The research explores hybrid switched-capacitor converter topologies and coupled magnetics to reduce the size of power converters while supporting fast changes in load.

Nagesh attended the meeting with Professor Robert Pilawa-Podgurski, joining researchers and industry partners to share the group’s work and discuss ongoing research across the center.

Read more about the meeting and student awards in Columbia Engineering’s event coverage.

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!