@inproceedings{tian_huang_teng_lu_bai_brown_mcammond_2016, title={A novel energy balanced variable frequency control for input-series-output-parallel modular EV fast charging stations}, DOI={10.1109/ecce.2016.7854730}, abstractNote={At present time, the most common electrical vehicle (EV) chargers employ a two-stage design, i.e., a front-end AC/DC stage + an isolated DC/DC converter. In this paper, an isolated dual-active-bridge (DAB) based single-stage AC/DC converter was proposed, which has the power-factor-correction (PFC) and zero-voltage-switching (ZVS) functions over the full-load range. By reducing one power stage and eliminating the large DC link capacitor, a high efficiency and high power density are achieved. Such topology can be used as a modular building block to scale up to 50kW by serial connecting the input terminals and paralleling output terminals. A novel energy-balanced variable switching frequency control for such input-series-output-parallel (ISPO) modular designed is proposed. A single-phase d-q transformation is implemented to achieve zero steady-state error. Simulation analysis and experimental validation are presented.}, booktitle={2016 ieee energy conversion congress and exposition (ecce)}, author={Tian, Q. and Huang, A. Q. and Teng, H. and Lu, J. C. and Bai, K. and Brown, A. and McAmmond, M.}, year={2016} }
 @inproceedings{tian_huang_bai_lu_teng_mcammond_brown_2016, title={A novel light load performance enhanced variable-switching-frequency and hybrid single-dual-phase-shift control for single-stage dual-active-bridge based AC/DC converter}, DOI={10.1109/iecon.2016.7793438}, abstractNote={Full-bridge power-factor-correction (PFC) front-end + dual-active-bridge (DAB) AC/DC topology is widely used in industry, e.g., electrical vehicle on-board charger. Such two-stage topology limits the system efficiency, and the bulky DC link bus capacitor makes the system power density relatively low. Compared to the two-stage design, the single-stage design, unfolding bridge + DAB, eliminates the bulky DC link bus capacitor and operates the front-end with only 60Hz switching frequency, thereby has the potential to increase the system power density and efficiency. A novel variable-switching-frequency and hybrid single-dual-phase-shift (VSF-SDPS) control strategy is proposed and analyzed for the DAB based single-stage topology. The proposed VSF-SDPF control consists of two phase shifts to guarantee Zero-Voltage-Switching (ZVS) over the full range of the AC line voltage, and frequency modulation to achieve boost PFC. The conventional front-end PFC is simplified to an unfolding bridge by changing DAB control strategy to achieve PFC and ZVS at the same time. Besides, a special ZVS boundary is utilized to solve the grid current distortion problem when the switching frequency saturated, which is especially severe at light load condition. Simulation results and experimental validation are presented under 50Vrms AC line voltage and 200V DC battery voltage test condition.}, booktitle={Proceedings of the iecon 2016 - 42nd annual conference of the ieee industrial electronics society}, author={Tian, Q. and Huang, A. Q. and Bai, H. and Lu, J. C. and Teng, H. and Mcammond, M. and Brown, A.}, year={2016}, pages={1227–1232} }
 @inproceedings{huang_wang_tian_zhu_chen_yu_2016, title={Medium voltage solid state transformers based on 15 kV SiC MOSFET and JBS diode}, DOI={10.1109/iecon.2016.7793121}, abstractNote={This paper discusses the advancements in the development of the medium voltage solid state transformer (SST) based on 15 kV SiC MOSFET and JBS diode. Designed for 7.2 kV single phase distribution grid applications, the medium voltage SST converts high voltage AC to low voltage 240/120V ac. The use of ultra-high voltage SiC devices allows the simplification of the power conversion circuit topology. This paper presents the characteristics of the high voltage SiC MOSFET devices as well as the topology innovations to achieve ultra-efficient SST design. Specifically, three different designs are discussed which utilize three-stage, two-stage and single stage power conversion topologies to achieve the AC to AC conversion.}, booktitle={Proceedings of the iecon 2016 - 42nd annual conference of the ieee industrial electronics society}, author={Huang, A. Q. and Wang, L. and Tian, Q. and Zhu, Q. L. and Chen, D. and Yu, Wensong}, year={2016}, pages={6996–7003} }