On April 24, ABB American R&D Center scientist Dr. Xiaoqing Song came to LAPS for academic exchanges.
During his visit, Dr. Song Xiaoqing gave a report entitled "Development and characterization of Hybrid SiC Power Devices" to the teachers and students of our team. The report was chaired by Professor Li Xuebao of Institute of Electromagnetic and Superconductive Engineering, and attracted many doctoral students, graduate students and international students from the institute.
Dr. Song Xiaoqing gave a special report for more than two hours. Firstly, he introduced the development history of power semiconductor devices and pointed out the disadvantages of current wide bandgap power devices. On this basis, he proposed the concept of hybrid power switches, and introduced the design and challenges of three typical hybrid power switches.
Dr. Song pointed out that wide bandgap power devices have excellent characteristics such as high temperature, high voltage, high frequency and low loss, but their high cost and low reliability have become a major challenge restricting their commercialization, so hybrid power devices came into being. Dr. Song introduced three kinds of hybrid power devices designed by his team, including FREEDOM Pair、FREEDOM Super-Cascode and ETO Thyristor. Among them, FREEDOM Pair combined Si IGBT and SiC MOSFET, The tradeoff between Si and SiC is made to achieve the best performance-to-price ratio; FREEDOM Super-Cascode developed a 15kV/40A FREEDM Super-cascode with high frequency, low cost and strong heat dissipation ability, based on the principle that several low voltage devices are connected in series to achieve high voltage level. At the same time, Dr. Song analyzed the problem of voltage equivalence; ETO Thyristor achieves excellent performances of 22kV ultra-low leakage current, ultra-low forward voltage drop, high current switching off, wide safe working area, 225 C high temperature operation, and can be applied to 7.2kV/200A hybrid solid-state circuit breaker. At the end of the report, Dr. Song pointed out that hybrid power devices face greater challenges, including optimizing the three-terminal FREEDOM Pair switch, achieving higher blocking voltage of FREEDOM Super-Cascode, series-parallel design, and further exploring the safe working area of SiC ETO.
At the end of the report, students asked Dr. Song about the positive temperature characteristics of ETO, the power level of SiC device tolerance and some theoretical introductions in the report. Dr. Song Xiaoqing patiently responded to the questions and made an extended introduction, which provided students with broad ideas. The meeting ended with warm applause from the students.
Profile of Dr. Song Xiaoqing:
Song Xiaoqing is a scientist at ABB American R&D Center. In 2009, 2012, he received his bachelor's degree and master's degree from Automation College of Beijing University of Technology, and his doctorate in electrical engineering from North Carolina State University in 2017. The main research fields include wide bandgap semiconductor power device characteristic testing and application, solid state circuit breaker and hybrid solid state circuit breaker. He is the senior member of IEEE who has published more than 30 papers in IEEE journals and conferences. In 2016, he was awarded EPE distinguished young scholar award. He has long been a reviewer of SiC power devices and solid-state circuit breakers in several IEEE journals. He has served as chairman of APEC and ECCE meetings for many times.
