This paper presents the study and evaluation of a medium-voltage grid-tied cascaded H-bridge (CHB) three-phase inverter for battery energy storage systems using SiC devices as an enabling technology. The high breakdown voltage capability of SiC devices provide the advantage to significantly minimize the complexity of the CHB multilevel converter, with less power loss compared to when Silicon (Si) devices are used. The topology in this study has been selected based on high voltage SiC devices. In order to reach 13.8 kV, a nine-level CHB is needed when using 6.5 kV SiC MOSFETs. However, if 10 kV SiC MOSFETs are used, only five-levels of the CHB are required. The controls were developed, simulated and verified through an experimental prototype. The results from the scaled-down prototype proved the controls and the verification of the performance of five-level CHB three-phase inverter. For the system reliability, both open-loop and short-circuit faults are analyzed.
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This content will become publicly available on May 17, 2025
Silicon Carbide MOSFETs Aging Testing Platform for EV Chargers Using Power Cycling
As the widespread adoption of electric vehicles (EVs) keeps increasing, EV charger reliability is becoming critical to provide a satisfactory charging experience for EV users. Wide-bandgap semiconductors such as silicon Carbide (SiC) MOSFETs have been widely deployed in EV chargers for high efficiency, high power density, and thermal capabilities. However, the aging of SiC MOSFETs has not been fully studied with available aging data lacking significantly in the literature. This paper addresses the EV charger reliability problem by developing a new aging test platform for SiC MOSFETs that are commonly used in various EV chargers, collecting aging data with analysis to provide a new understanding of SiC MOSFET aging, and providing new insights into online EV charger health monitoring system design and development.
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- Award ID(s):
- 2239169
- PAR ID:
- 10526860
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-5133-0
- Page Range / eLocation ID:
- 655 to 660
- Subject(s) / Keyword(s):
- MOSFET, Power system measurements, Silicon carbide, Thermal engineering, Aging, Reliability engineering, Thermal stresses
- Format(s):
- Medium: X
- Location:
- Chengdu, China
- Sponsoring Org:
- National Science Foundation
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