Douglas Hopkins
Publications
- A 400W, 250kHz (2kW Peak) Integrated GaN Half Bridge Power Module in a Non-Isolated Buck Converter , 2024 IEEE APPLIED POWER ELECTRONICS CONFERENCE AND EXPOSITION, APEC (2024)
- FET Junction Temperature Monitoring Using Novel On-Chip Solution , 2024 IEEE APPLIED POWER ELECTRONICS CONFERENCE AND EXPOSITION, APEC (2024)
- Advanced GaN IPM for High-Frequency Converter Applications Enabled with Thin-Substrates , 2023 IEEE Applied Power Electronics Conference and Exposition (APEC) (2023)
- Analysis and Characterization of Four-quadrant Switches based Commutation Cell , 2023 IEEE Applied Power Electronics Conference and Exposition (APEC) (2023)
- Bidirectional Three-phase Current Source Converter based Buck-boost AC/DC System using Bidirectional Switches , 2023 IEEE TRANSPORTATION ELECTRIFICATION CONFERENCE & EXPO, ITEC (2023)
- Design & Integration of Solid-State Circuit Protection , IEEE Applied Power Electronics Conference (2023)
- Double Sided Integrated GaN Power Module with Double Pulse Test (DPT) Verification , IMAPSource Proceedings (2023)
- Finite Element Analysis and Fatigue Life Prediction of A Laterally Conducting Gan-Based Power Package Under Thermal CyclingASME 2023 Int’l Mechanical Eng. Congress and Exposition , ASME 2023 Int’l Mechanical Eng. Congress and Exposition (2023)
- Methodologies of Cascading to Realize High Voltage Cascaded Super Cascode Power Switch , IEEE Journal of Emerging and Selected Topics in Power Electronics (2023)
- Power Conversion Systems Enabled by SiC BiDFET Device , IEEE POWER ELECTRONICS MAGAZINE (2023)
Grants
Material Testing Agreement to test client materials.
A senior team who co-authored the Integrated Power Electronics (IPE) Chapter 10 of the IEEE Heterogeneous Integration Roadmap (HIR), brings over 100 years of industry and academic experience to: ??? Define an Exemplar 3DHI Power Microsystem (3DHIP) which tightly integrates arrays of gallium nitride (GaN) transistors, silicon-on-insulator (SOI) gate drivers and capacitors in a "half-bridge circuit??? building block and used with integrated passives (e.g., inductor) technologies. The 3DHIPs significantly improve efficiency and power density of IVRs (Integrated Voltage Regulators) and board-mount PSiPs (power supplies in package) to meet DARPA???s goals in 3DHI with focus on power. ??? Define the design, process and equipment requirements for an open-access 3DHIP Manufacturing Center drawing from industry-leading tool and components suppliers, and facility operators such as Applied Materials, Micross Components, X-Celeprint, NCSU-Nanofabrication Facility, Hesse Mechatronics US, Tyndall National Institute (Ireland), selected HIR-IPE team members, Power America, NCSU Faculty, and others to be added during the Phase-0.
Demonstration of 100 kW SiC Inverter with Soft-Switching dv/dt Filter and Ultra High Efficiency for Motor Drives, PowerAmerica MIP task 3.31
This work brings together three innovations: Newly developed 4-Quadrant Single Die SiC-JBSFET based Power Semiconductor Switches (4-QPSs) are used to enable a new breed of Power Conversion Systems (PCS) for photovoltaic (PV) applications based on a cyclo-converter topology, and that are combined into two new module packaging schemes for creation of ultra-high density, low cost power conversion cells. Novel DC/AC power converter topologies leveraging high frequency (HF) transformer technology coupled with SiC based 4-QPS are proposed for commercial and household PV inverter applications. This combined technology development of the scalable power converter cell as a building block from the monolithic 4-QPS device die, package and converter will meet and exceed the higher efficiency, power density, specific power and relative cost metrics envisioned in the FOA. This is specifically done by innovative implementation of a SiC based 4-QPS based on monolithically integrated die which can be scaled up in current and voltage due to majority carrier characteristics. Innovative module packaging provides integration of bidirectional 4-QPS to construct power converter cells to achieve higher efficiency, power density and specific power metrics as required by the FOA. The proposed topologies can be designed to satisfy all current and emerging interconnection, interoperability, and grid support functional requirements while also achieving a combination of increased efficiency, power density, reliability, and reduced costs as compared to conventional solar inverters. The proposed module offers flexible integration of multiple types of Distributed Energy Resources including Energy Storage, Fuel Cells, and Responsive Loads on the PV plant side for optimized delivery of power to the grid. Prototype hardware will be demonstrated at power levels and voltage ratings relevant for commercial scale installations up to 50 kW using (1) newly developed SiC based 4-QPS devices (2) custom packaging of the 4-QPS (3) HF transformer technologies based upon state-of-the-art commercial magnetic cores. Simulation studies will also be performed in parallel to demonstrate the advanced grid-support features enabled by the proposed topologies. The proposed concepts leverage many recent investments and capabilities established through PowerAmerica Semiconductor Power Device Electrical Characterization Station, the NCSU FREEDM Center, X-Fab Foundry, NCSU Designed Foundry Process Developed at X-Fab, NCSU Laboratory for Packaging Research in Electronics Energy Systems (PREES) amongst others. The project scope and teaming structure seeks to transition the technologies under development to major US manufacturers to accelerate commercialization and enable successful realization of broader deployment of affordable and reliable PV-based generation throughout the US energy infrastructure.
NCSU is proposing R&D in power electronics packaging for ultra-harsh environments, which use Wide Band Gap (WGB) power semiconductor devices, such as SiC and GaN. For long-term reliability and extreme ruggedness, packaging of power modules, including intelligent power modules (e.g. inclusion of gate drivers, fault detection and actuation circuits), is based on metal-ceramic and organic material. Approaches leverage early basic packaging developments in Phase-I (Year-1) that will lead to final system developments of power modules in Phases II & III in Years 2&3, respectively. Approaches are divided by technology for lower voltage to higher voltage (i.e. 0.6kV to >30kV) applications. Research is conducted in development of highly thermally conductive packages, identification of challenges in dynamic high E-Field structures, and use of additive manufacturing to create or augment power electronic packaging features. Supportive research is conducted to quantify boundary conditions for application to pulsed-power, as well as to support scaling for lower power.
PREES proposes to fabricate a High Power Capacitor Tester (HPCT). PREES has a Full Power Test Platform (FPTP) for testing Wide Band Gap Power Semiconductors up to 8,000V and 200A continuous. Since the FPTP incorporates features what are not needed for capacitor testing, PREES will only include basic circuitry and controls in the HPCT, and will limit demonstrating and certifying electrical performance for capacitor testing.
The SuperCascode Power Module (SCPM) is a new approach to high voltage switches introduced by USCi. Inc. The SCPM uses a series string of SiC JFETs in a cascode configuration switched with a Si MOSFET. This one year project shall develop a medium voltage (MV) 6.5kV/50A/100A SCPM with extension to 200A, and a continuous Full-Power emulation Test Platform (FPTP) based on the ERC concept, which shall demonstrate full-power in-situ performance of the SCPM.
In this project, NCSU??????????????????s FREEDM Systems Center is to collaborate with ABB Inc. and Cree Inc. to develop a high voltage, high current SiC power devices based solid state DC circuit breaker for shipboard DC distribution system.
Sandia National Laboratories (SNL) is developing the capability to process alternative gate oxide materials for wide bandgap semiconductor power electronics devices. These devices are key to future high-efficiency power converters for both alternative power generation and energy storage. This project will refine metal-oxide-semiconductor capacitance models for oxides on GaN and extending to oxides on SiC. These models will be extended to investigate intrinsic gate capacitance to include extrinsic sources, including other transistor contacts and packaging influences that are present in packaged power semiconductor devices used in energy storage power conversion systems.
Primary goals are to demonstrate a high-efficiency integrated power stage for a 3-phase SST, explore advanced packaging techniques using additive manufacturing, and develop full-power testing capability for PSD SiC and GaN devices