@inproceedings{vechalapu_negi_bhattacharya_2016, title={Comparative performance evaluation of series connected 15 kV SiC IGBT devices and 15 kV SiC MOSFET devices for MV power conversion systems}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85015367464&partnerID=MN8TOARS}, DOI={10.1109/ecce.2016.7854936}, abstractNote={The 10–15kV SiC MOSFET and 15kV SiC IGBT (2 μm and 5 μm buffer layer) are the state of the art high voltage devices designed by Cree Inc. These devices are expected to increase the power density of converters and the demonstration of these devices in applications like Solid State Transformers (SST) have been reported up to 4.16 kV–13.2 kV grid connection. It is interesting to investigate the performance of the devices in very high voltage (≥13.2 kV) application, where the series connection of devices is required. Therefore, this paper addresses design considerations of the series connection of 15 kV Silicon Carbide (SiC) IGBT devices and a series connection of 10 kV/15 kV Silicon Carbide (SiC) MOSFET devices in two separate independent cases and their experimental comparison.}, booktitle={ECCE 2016 - IEEE Energy Conversion Congress and Exposition, Proceedings}, author={Vechalapu, K. and Negi, A. and Bhattacharya, Subhashish}, year={2016} }
 @inproceedings{vechalapu_negi_bhattacharya_2016, title={Performance evaluation of series connected 15 kV SiC IGBT devices for MV power conversion systems}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85015420529&partnerID=MN8TOARS}, DOI={10.1109/ecce.2016.7855343}, abstractNote={The 15kV SiC IGBT (2 μm buffer layer) with chip area of 8.4 × 8.4 mm2 is the state of the art high voltage device designed by Cree Inc. This device is expected to increase the power density of converters and the demonstration of the device in applications like Solid State Transformers has been published. Therefore, it is interesting to investigate the performance of the device in very high voltage (HV) application, where the series connection of devices is required. This paper addresses design considerations of the series connection of 15kV SiC IGBT devices for high voltage converter applications. A simple RC snubber has been used to control both ‘dv/dt’ and dynamic voltage balancing during turn-off. The experimental results show that there is a significant difference in the static and dynamic voltage sharing between two unmatched 15kV SiC IGBTs without active compensation method. With external RC snubber at total DC bus voltage of 10 kV, the difference in dynamic voltage between the two 15 kV SiC IGBT devices during turn-off transition nearly negligible. Also with external snubber, the total turn-off dv/dt of less than ‘5 kV/ μs’ is achieved across each device of two series connected 15kV SiC IGBTs. Furthermore, optimization of RC snubber to minimize semiconductor switching losses and total losses per device including the snubber resistor losses in series connection has been presented.}, booktitle={ECCE 2016 - IEEE Energy Conversion Congress and Exposition, Proceedings}, author={Vechalapu, K. and Negi, A. and Bhattacharya, Subhashish}, year={2016} }