@article{agarwal_prabowo_bhattacharya_2023, title={Analysis and Design Considerations of Input Parallel Output Series-Phase Shifted Full Bridge Converter for a High-Voltage Capacitor Charging Power Supply System}, volume={59}, ISSN={["1939-9367"]}, url={https://doi.org/10.1109/TIA.2023.3276353}, DOI={10.1109/TIA.2023.3276353}, abstractNote={Capacitor charging power supply (CCPS) is used for impulse-power applications such as electromagnetic rail guns, flash lamps, medical sterilization, and rock crushing, among many other application fields. This article describes the design and analysis of an Input Parallel Output Series-Phase Shifted Full Bridge converter for CCPS. The proposed system has a low output current ripple to improve the lifetime of the high-voltage pulsed capacitor. Design considerations of topology's electrical parameters such as HF transformer's leakage inductor and output inductor for the CCPS application are presented. The intermediate DC-link capacitance is provided as an energy storage element to minimize the disturbances (power variation) on the source for the CCPS application. Analysis and sizing of the capacitance for two different charging methods are analyzed and compared. A controller design procedure for the Active Front End Converter (AFEC) is also included to ensure near-constant power drawn, rejecting the load disturbances. Finally, a complete design procedure for the whole CCPS system is presented. Design and simulation results are presented for a rated system, followed by experimental results from a scaled-down hardware prototype to validate the design.}, number={5}, journal={IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS}, author={Agarwal, Apoorv and Prabowo, Yos and Bhattacharya, Subhashish}, year={2023}, month={Sep}, pages={6037–6050} }
 @article{prabowo_iyer_agarwal_bhattacharya_aeloiza_2023, title={Modular Hybrid Transformers Toward Grid Resilience: Efficiency Analysis and Operation}, volume={12}, ISSN={["1557-9948"]}, url={https://doi.org/10.1109/TIE.2023.3340215}, DOI={10.1109/TIE.2023.3340215}, abstractNote={This article proposes modular hybrid transformer architectures to improve grid resilience. The conventional line-frequency transformer is augmented with a partially rated power electronics converter to realize a hybrid transformer system. The proposed modular approach is envisioned to replace a single large power low-frequency transformer with multiple smaller rated hybrid transformer systems during disasters and emergencies. A hybrid transformer system enables controlled current sharing between the modular system. The efficiency analysis and operational aspects of a modular hybrid transformer architecture are thoroughly discussed in this article. The proposed efficiency analysis combines empirical data and numerical analysis of the overall modular hybrid transformer system. The optimum current sharing ratio to achieve maximum efficiency operation is presented for the proposed architectures. One of the proposed architectures (Configuration B) also offers load voltage regulation in case of grid voltage sag/swell occurrence. The proposed concept and analyses are experimentally validated through a scaled-down hardware prototype. The total ownership cost of the proposed system is also presented to emphasize the potential cost-benefits. Supplementary video files accompany this article to showcase the extensive experimental validation cases.}, journal={IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS}, author={Prabowo, Yos and Iyer, Vishnu Mahadeva and Agarwal, Apoorv and Bhattacharya, Subhashish and Aeloiza, Eddy}, year={2023}, month={Dec} }
 @article{agarwal_prabowo_bhattacharya_2021, title={Analysis and Design Considerations of Input Parallel Output Series-Phase Shifted Full Bridge Converter for a High-Voltage Capacitor Charging Power Supply}, ISSN={["2150-6078"]}, DOI={10.1109/ECCE-Asia49820.2021.9479247}, abstractNote={Capacitor charging power supplies (CCPS) are used for pulsed-power applications such as electromagnetic guns, radar applications, and pulsed lasers for aesthetic medicine, among many other application fields. This paper describes the design and analysis of an Input Parallel Output Series-Phase Shifted Full Bridge converter (IPOS-PSFB) for CCPS. In CCPS application, attaining long-lifetime of the high voltage (HV) pulsed capacitor is critical. The proposed system possesses low output current ripple to improve the lifetime of the pulsed capacitor. With the output voltage not being constant, modifications on the output current ripple equations for selecting an appropriate output inductor parameter is required. The proposed system employs a Constant Current - Constant Power (CC-CP) charging profile instead of a Constant-Current (CC) charging profile. Comparative evaluation of the CC-CP charging profile is presented to elucidate the advantage of employing CC-CP. Circuit simulation and experimental results from a hardware prototype are included to validate the design and to show the effectiveness of the proposed system.}, journal={2021 IEEE 12TH ENERGY CONVERSION CONGRESS AND EXPOSITION - ASIA (ECCE ASIA)}, author={Agarwal, Apoory and Prabowo, Yos and Bhattacharya, Subhashish}, year={2021}, pages={1068–1075} }
 @article{agarwal_anurag_kolli_kumar_bhattacharya_2021, title={Design considerations of 6.5kV enabled three-level and 10kV enabled two-level medium voltage SST}, ISSN={["2329-3721"]}, DOI={10.1109/ECCE47101.2021.9595367}, abstractNote={The advent of medium voltage silicon carbide (SiC) power semiconductor devices (6.5kV and 10 kV) has opened up the possibilities of looking into different converter topologies for the MV grid interfaced applications. A medium voltage mobile utility support equipment-based three-phase solid-state transformer (MUSE-SST) system is one such application aimed to interconnect a three-phase 4160 V/60 Hz grid to a three-phase 480 V/60 Hz grid to provide a shore-to-ship power interface for naval vessels. The system can be realized by both 10 kV SiC MOSFET and 6.5kV SiC MOSFET employing a two-level and three-level architecture respectively. The aim of this paper is to understand the thermal challenges and provides detailed design considerations of the two MV device-based architectures for a system scale-up to 500kVA rating. Device characteristics for both 6.5kV and 10kV SiC MOSFETs have been evaluated from experimental results. Based on these experimental data, the thermal performance of these devices enabled converter architecture is compared using elctro-thermal simulation-based loss comparison.}, journal={2021 IEEE ENERGY CONVERSION CONGRESS AND EXPOSITION (ECCE)}, author={Agarwal, Apoorv and Anurag, Anup and Kolli, Nithin and Kumar, Ashish and Bhattacharya, Subhashish}, year={2021}, pages={282–289} }