Peer-reviewed journals

(J4)    N.M. Ellis and R.C.N. Pilawa-Podgurski, “The Symmetric Dual Inductor Hybrid (SDIH) Converter for Direct 48V-to-PoL Conversion” Early Access, IEEE Transactions on Power Electronics. [Paper]

(J3)    S. Coday, N.M. Ellis, N. Stokowski, and R.C.N. Pilawa-Podgurski, “Design and Flight Qualification of a Flying Capacitor Multilevel Converter for Electric Aircraft Applications” Early Access, IEEE Transactions on Transportation Electrification. [Paper]

(J2)    S. Coday, N.M. Ellis, and R.C.N. Pilawa-Podgurski, “Modeling and Analysis of Shutdown Dynamics in Flying Capacitor Multilevel Converters” in press, IEEE Transactions on Power Electronics. [Paper]

(J1)    N.M. Ellis and R. Amirtharajah, "Large Signal Analysis on Variations of the Hybridized Dickson Switched-Capacitor Converter," in IEEE Transactions on Power Electronics, vol. 37, no. 12, pp. 15005-15019, Dec. 2022. [Paper]

Journals under peer review / pre-print

(J10)  S.S. Cheema, N. Shanker, S.L. Hsu, J. Schaadt, N.M. Ellis, M. Cook, R. Rastogi, R.C.N. Pilawa-Podgurski, J. Ciston, M. Mohamed, S. Salahuddin “Giant Energy Storage Microsupercapacitors via Negative Capacitance Antiferroelectric Superlattices”, under peer review, Nature. [Paper]

(J7)    N.M. Ellis, A. Jackson, S. Coday, R.C.N. Pilawa-Podgurski, “The Capacitively Isolated Dual Extended LC-tank Hybrid Switched-Capacitor Converter”, under peer review. 

(J6)    N. M. Ellis, R. Iyer, R.C.N. Pilawa-Podgurski, “Bi-directional synchronous bootstrapping for high level count multi-level converters”, under peer review. 

(J5)    N. M. Ellis, N. Brooks, M. Blackwell, R. Abramson, S. Coday, R. Pilawa-Podgurski, “A General Approach to Optimization and Control of Resonant Switched Capacitor Converters Using Peak Energy Storage and Switch Stress Including Ripple Considerations”, conditionally accepted subject to revision, IEEE Transactions on Power Electronics. [Paper]

Journals in preparation

(J9)    R. Iyer, N. M. Ellis, R. C. N. Pilawa-Podgurski, “A charge pump gate drive power delivery technique with extended operating range for use in multilevel converters”. [Paper]

(J8)    N.M. Ellis, R. Abramson, R.C.N. Pilawa-Podgurski, “Modified Split-Phase Switching for Improved Flying Capacitor Utilization in Step-down Applications”. [Paper]

Peer-reviewed conference proceedings

(C23) L. Horowitz, N.M. Ellis, R.C.N. Pilawa-Podgurski, “Decoupling Device for Small Commutation Loop and Improved Switching Performance with Large Power Transistors”, in IEEE Applied Power Electronics Conference (APEC), 2023. [Paper]

(C22) Y. Zhu , L. Horowitz, T. Ge, N.M. Ellis, R.C.N. Pilawa-Podgurski, “A 500-A/48-to-1-V Switching Bus Converter: Hybrid Switched-Capacitor Voltage Regulator with 94.7% Peak Efficiency and 464-W/in^3 Power Density”, in IEEE Applied Power Electronics Conference (APEC), 2023. [Paper]

(C21) H. Sambo, Y. Zhu, N.M. Ellis, R. C. N. Pilawa-Podgurski, “Autotuning of Resonant Switched-Capacitor Converters for Terminal Capacitance Reduction and Soft-Switching Operation”, in IEEE Applied Power Electronics Conference (APEC), 2023. [Paper]

(C20) S. Coday, M. Blackwell, N.M. Ellis, A. Barchowsky, and R. C. N. Pilawa-Podgurski, “Design and Implementation of a GaN-Based Capacitively-Isolated Hybrid Dickson Converter for Space Applications”, in IEEE Applied Power Electronics Conference (APEC), 2023. [Paper]

(C19) R. Abramson, N. Brooks, S. Coday, M. Blackwell, N.M. Ellis, R. C. N. Pilawa-Podgurski, “Multi-Ratio Operation of Flying Capacitor Multilevel Converters At and Above Resonance”, in IEEE Southern Power Electronics Conference (SPEC), 2022. [Paper]

(C18) N.M. Ellis, L. Horowitz, R. Iyer, N. Brooks, R.C.N. Pilawa-Podgurski, “An Actively Balanced Distributed Regenerative Snubber with Reduced Part Count in Multi-Level Power Converters”, in IEEE Energy Conversion Congress and Exposition (ECCE), 2022. [Paper], [Video]

(C17) M.E. Blackwell, S. Krishnan, N.M. Ellis, R.C.N. Pilawa-Podgurski, “Direct 48 V to 6 V Automotive Hybrid Switched-Capacitor Converter with Reduced Conducted EMI”, IEEE Workshop on Control and Modeling for Power Electronics (COMPEL), 2022. [Paper]

(C16) J. Zou, N. Brooks, S. Coday, N.M. Ellis, R.C.N. Pilawa-Podgurski, “On the Size and Weight of Passive Components: Scaling Trends for High Density Power Converter Designs”, IEEE Workshop on Control and Modeling for Power Electronics (COMPEL), 2022, pp. 1-7. [Paper]

(C15) N. Brooks, S. Coday, M. Blackwell, R. Abramson, N.M. Ellis, R.C.N. Pilawa-Podgurski, “Operation of Flying Capacitor Multilevel Converters At and Above Resonance”, IEEE Workshop on Control and Modeling for Power Electronics (COMPEL), 2022. [Paper] [Best Paper Award]

(C14) N.M. Ellis, R.C.N. Pilawa-Podgurski, “A Symmetric Dual-Inductor Hybrid Dickson Converter for Direct 48V-to-PoL Conversion”, IEEE Applied Power Electronics Conference (APEC), 2022. [Paper]

(C13) A. Jackson, N.M. Ellis, R.C.N. Pilawa-Podgurski, “A Capacitively-Isolated Dual Extended LC-tank Converter with 50% Two-Phase Operation at Even Conversion Ratios”, IEEE Applied Power Electronics Conference (APEC), 2022. [Paper] [Best Technical Lecture Award]

(C12) S. Coday, N.M. Ellis, R.C.N. Pilawa-Podgurski, “Design and Implementation of a (Flying) Flying Capacitor Multilevel Converter”, IEEE Applied Power Electronics Conference (APEC), 2022. [Paper] [Best Technical Lecture Award]

(C11) S. Coday, N.M. Ellis, R.C.N. Pilawa-Podgurski, “Modeling and Analysis of Shutdown Dynamics in Flying Capacitor Multilevel Converters”, IEEE Workshop on Control and Modelling of Power Electronics Conference (COMPEL), 2022. [Paper]

(C10) N.M. Ellis, R.C.N. Pilawa-Podgurski, “Modified Split-Phase Switching with Improved Fly Capacitor Utilization in a 48V-to-POL Dual Inductor Hybrid-Dickson Converter”, IEEE Energy Conversion Congress and Exposition (ECCE), 2021. [Paper], [Video]

(C9)   S. Coday, N.M. Ellis, Z. Liao, R.C.N. Pilawa-Podgurski, “A Lightweight Multilevel Power Converter for Electric Aircraft Drivetrain”, IEEE Energy Conversion Congress and Exposition (ECCE), 2021. [Paper]

(C8)   R. Iyer, N.M. Ellis, R.C.N. Pilawa-Podgurski, “A High-Efficiency Charge-pump Gate Drive Power Delivery Technique for Flying Capacitor Multi-level Converters with Wide Operating Range”, IEEE Energy Conversion Congress and Exposition (ECCE), 2021. [Paper]

(C7)   N.M. Ellis, R. Iyer, R.C.N. Pilawa-Podgurski, “A Synchronous Boot-strapping Technique with Increased On-time and Improved Efficiency for High-Side Gate-drive Power Delivery”, Workshop on Wide Bandgap Power Devices and Applications in Asia (WiPDA-Asia) 2021. [Paper], [Video]

(C6)   N.M. Ellis, R. Amirtharajah, “A Resonant Dual Extended LC-Tank Dickson Converter with 50% Two-Phase Operation at Odd Conversion Ratios”, IEEE Applied Power Electronics Conference (APEC), 2021.  [Paper], [Video] [Best Technical Lecture Award]

(C5)   N.M. Ellis, R. Amirtharajah, “Reducing COSS Switching Loss in a GaN-based Resonant Cockcroft-Walton Converter Using Resonant Charge Redistribution”, IEEE Energy Conversion Congress and Exposition 2020. [Paper], [Video]

(C4)   N.M. Ellis, E. Sousa, R. Amirtharajah, “A GaN-Switched High-Speed Resonant Gate Driver with Variable Gain and a Capacitively Decoupled High-Side N-FET”, IEEE Energy Conversion Congress and Exposition 2020. [Paper], [Video]

(C3)   N.M. Ellis, R. Amirtharajah. “A Resonant 1:5 Cockcroft-Walton Converter Utilizing GaN FET Switches with N-Phase and Split-Phase Clocking” In IEEE Applied Power Electronics Conference and Exposition (APEC), 2020. [Paper]

(C2)   N.M. Ellis, R. Amirtharajah. “A Resonant Cockcroft-Walton Switched-Capacitor Converter Achieving Full ZCS and >10kW/inch3 Power Density” In IEEE Energy Conversion Congress and Exposition (ECCE), pp. 4378-4384, 2019. [Paper]

(C1)   S.H. Nguyen, N.M. Ellis, and R. Amirtharajah. “Powering smart Jewelry using an RF energy harvesting necklace” IEEE MTT-S International Microwave Symposium (IMS), pp. 1-4. 2016. [Paper]

Conference proceedings under peer review

(C24) L. Horowitz, N. Brooks, N.M. Ellis, R.C.N. Pilawa-Podgurski, “The Flying Capacitor LLC Converter: A Hybrid Switched Capacitor Converer with Galvanic Isolation for Large Ste-Down Applications”.

(C25) N. Biesterfeld, Y. Zhu, R. Iyer, N.M. Ellis, R.C.N. Pilawa-Podgurski, “Steady-State Analysis of the Series-Capacitor Buck Converter in Discontinuous Capacitor Voltage Mode”.

(C26) Y. Zhu, T. Ge, N.M. Ellis, J. Zou, R.C.N. Pilawa-Podgurski, “A 48V-to-1V Switching Bus Converter for Ultra-High-Current Applications”.

(C27) N.M. Ellis, H. Sambo, R.C.N. Pilawa-Podgurski, “Closed-Loop Split-Phase Control Applied to the Symmetric Dual Inductor Hybrid (SDIH) Converter”.

Theses

(T2)   N. M. Ellis, “Hybrid switched-capacitor power converter techniques”, Ph.D. Thesis, Department of Electrical and Computer Engineering, University of California, Davis, 2020.

(T1)   N. M. Ellis, “High Frequency Multi-Phase Buck Converter for Mobile Applications”, M.S. Thesis, Department of Electrical and Computer Engineering, University of California, Davis, 2017.

Patents

N. M. Ellis, R.C.N. Pilawa-Podgurski “A Symmetric Dual-Inductor Hybrid Dickson Power Converter Topology”, Provisional Patent Filed.

N. M. Ellis, R.C.N. Pilawa-Podgurski “Bi-Directional Synchronous Bootstrapping” Patent Pending.

N. Ellis, “Multiple-Phase Switching Technique for a Switched-capacitor Voltage Converter that achieves Full-zero-current Switching”, Patent Pending.

N. Ellis and J. Tugwell, “System and method for monitoring core body temperature”, WIPO (PCT) WO2018033795A3, 2017.

N. Ellis and J. Foody, “Method and System for Determination of Core Body Temperature”, WO/2018/033799, 2017.