Subhashish Bhattacharya

Integrated time nanosecond pulse irreversible electroporation (INSPIRE) is a minimally invasive treatment for inoperable solid tumors developed by the PI. This treatment uses ultrashort electrical pulses to destabilize the cell membrane and induce a tunable combination of necrotic and apoptotic cell death within a well-defined volume. The therapy is implemented by introducing one or more electrodes into the tumor then delivering a series of 500ns to 2000ns electrical pulses between an electrode and an external grounding pad. To enable treatment of tumors which occur near our around critical structures active temperature feedback is utilized to limit Joule heating and prevent deleterious thermal injury. We have validated the efficacy of INSPIRE treatments utilizing in vitro 3D tumor models, against murine tumors, in healthy liver parenchyma in vivo, and in a pre-clinical safety/efficacy trial in veterinary patients. Using a combination of ex vivo, in vivo, and computational results we hypothesize that INSPIRE will be a safe and effective treatment for the vast majority of liver tumors utilizing a single applicator approach and a compatible pulse generator capable of 1,000 to 10,000V outputs when active temperature control is utilized to prevent off-target thermal injury. This hypothesis will be tested through a combination of ex vivo validation and in vivo safety and efficacy studies in the proposed work.

The proposed research focuses on utilizing strategies for energy-synchronous direct antenna modulation (DAM) to both realize and quantify gains in the effective bandwidth-efficiency product of electrically small transmit systems. This work includes several aspects of the design and analysis of direct antenna modulation systems, including the study of metrics for comparing non-LTI DAM methods against fundamental bounds on LTI systems, considering device- and system-level efficiency measures, scaling and optimizing preliminary ����������������proof-of-concept��������������� DAM architectures to increase performance gains, development of an FPGA-based DAM prototype that does not rely on complex lab instrumentation to operate, and test and evaluation spanning analytic methods to over-the-air measurements.

CorePower Magnetics ARPA-e SCALEUP proposal on "Scaled In-Line Processing Facility for Permeability Engineered Nanocrystalline Magnetics". NCSU will perform research and testing of low voltage components produced from the new manufacturing facility.

Hepburn and Sons LLC teamed with the North Carolina State University (NCSU) proposes to design and optimize a megawatt class, solid state transformer rectifier (SSTR) supporting maintainability of the input power to the U.S. Navy electromagnetic aircraft launch system (EMALS). The design will convert 13.8kV AC to +-850V DC with modular, line-replaceable units (LRUs) that are compact and lightweight such that a single sailor may quickly and easily replace a hatchable failed unit. The team proposes an analysis of two alternative SSTR designs, implementing for both designs a multi-objective optimization of converter topology, device, and magnetics selections. The two designs will be optimized for thermal management, space, and weight requirements for a dramatic reduction of the current system���s mean time to repair (MTTR). A Phase I design concept down selection will leverage prior and ongoing solid state transformer efforts, exploring design options while evaluating mean time to failure of LRUs, ease and cost of LRU replaceability, and system performance. The first topology the team proposes is a high voltage device based SSTR. This SSTR uses a high voltage active front end (AFE) and medium frequency dual active bridge, high gain (DAB). The high side, input, consists of 20kV logical switches while the output will be realized with high current, medium volage devices. The high step-down gain of the DAB will be achieved with a high power, medium frequency transformer. The AFE and DAB converters will be in the neutral point clamped (NPC) configuration. The team will compare the high voltage concept with a cascaded cell SSTR based on medium voltage devices. This cell based SSTR uses several, four switch, H-bridge rectifiers and high frequency DABs. The cell inputs are connected in series while the outputs are connected in parallel. The cell DAB will utilize a unity gain, high frequency, transformer. The two proposed topologies can be realized with a variety of SiC devices. In this evaluation, the team proposes to compare topologies constructed of 10 kV, 3.3 kV, and 1.2 kV SiC MOSFET dies with SiC diodes. The project ream will also include new, JFET based, supercascode 6.5 kV+ SiC switches in the comparison. All high voltage devices are available to NCSU through the PowerAmerica device bank with high detail Saber models that will be used for co-simulations. The plan is to leverage existing simulation models to detail the two proposed design concepts��� performance and operating conditions. The team will join these results with their extensive wide band gap (WBG) device characterization and evaluation experience to determine optimal combinations of topology and semiconductor device selections. Then coupling this data with their extensive experience modelling and characterizing high power, medium frequency magnetics , the project team will provide co-optimized converter and magnetics design solutions. The proposed converter topology, medium frequency magnetics, and control procedures will enable unparalleled modularity and replacement ease for the U.S. Navy���s transformer rectifier.

To advance JDES electrification portfolio and to promote US manufacturing and competitiveness, John Deere together with NCSU is requesting DOE-VTO funding to develop ruggedized 700V battery-pack and integrate it with the diesel series electric drive systems, resulting in a new generation of powertrain for construction vehicles. The proposed new powertrain will include a state-of-the-art Battery Management System (BMS) to optimize the life of the battery in diesel engine hybrid solutions. The VTO funding will accelerate (TRL 2 to TRL 6 by end of project) John Deere������������������s technology development works for vehicles that will lead to significantly reduced greenhouse gas (GHG) emissions.

New low cost sensors (optical fiber, passive wireless) will be demonstrated for distributed temperature and current sensing with order of magnitude cost reduction. Inverters will also be exploited as ����������������virtual��������������� sensors and heterogeneous, distributed data will be collected, aggregated, and treated including leveraging Micro PMU systems for interoperability and cybersecurity with minimum communication system costs. Distributed analytics will be developed and exploited at component (edge), aggregator (micro PMU), and system (cloud) levels. Ultimately, an integrated sensing and measurement scheme will be demonstrated for full Behind the Meter (BTM) visibility of utilities focusing on traditionally under served rural electric cooperatives, including high value use cases clarifying pathways to future full scale deployment.

Low-Cost Compact Medium Voltage Connected DC Charging Infrastructure The goal of this project is to develop Solid-State Transformer (SST) architectures for Megawatt (MW)-level Electric Vehicle (EV) Fast Charger, emphasizing reduced capital cost. We will also investigate the benefits of the possible topologies in terms of efficiency, reliability, power density. A real-time controller hardware-in-the-loop will be used to validate the proposed concept. The expected integration of Photo-Voltaic (PV) cells and Battery Energy Storage System (BESS) require the implementation conforming to IEEE1547-2018.

The objective of the project is to research, develop, and test GaN technology equipped lightweight electric motors for use in vehicle applications

RAMJET: Realizing Advanced Magnetics for Jet Electrification Technologies Aviation and space applications are shifting towards more electrification as wide bandgap power electronics-based converters can meet the demands of existing mechanical systems. This results in systems with reduced weight and improved fuel efficiency. This requires careful design and utilization of magnetic materials as they enable energy transfer, system isolation, and regulation of electromagnetic interference while also constituting a large proportion of the new system weight and volume. It is hypothesized that system optimization of wide bandgap converters with soft magnetic materials developed with advanced post processing techniques can improve efficiency while reducing the weight and volume of systems that meet existing electrification needs. This work will provide NASA GRC with prototypes and a roadmap for maximizing the impact and utilization of advanced magnetic materials and component designs for use in future aviation and space applications.

Advances in grid-scale hardware and enabling technologies including materials, components, and component level modeling will play an important role in the modernization of the electricity transmission and distribution system. Large power transformers represent a major source of vulnerability and risk as catastrophic failures can represent major economic and social costs,driving the need for more standardized, modular, and readily deployable solid-state transformers. Iron core losses in distribution transformers represent a significant fraction of the overall losses in the transmission and distribution system. A rising prevalence of renewable and distributed energy resources is increasing the deployment of grid-tied power electronics converters. Advanced sensing and control devices including current transformers and variable impedance power flow controllers will play a key role in enabling active power flow control. Solid state power substations are also a key part of any electrical generation, transmission, and distribution system and they generally include transformers to (1) change voltage levels, (2) function as an interconnection between two transmission voltages, and (3) serve as control points for the flow of power to increase system reliability.