Prof. Yifei Wu
Xi'an Jiaotong University, China

Yifei Wu was born in Zhejiang, China. He is now a professor in Xi'an Jiaotong University (top young talent) and supported by the national youth talent plan. He has hosted over more than 10 scientific research projects including the NSFC, the Key R&D Program of Shaanxi Province, and the State Grid Corporation's Science and Technology Project. He also published more than 70 SCI/EI papers in high-level journals at home and abroad, including 30 SCI papers as the first/corresponding author. He is a senior member of IEEE, authorized 19 national invention patents, 10 U.S. patents, 2 European patents. He won the Second Prize of Science and Technology of Shaanxi Province.

Speech Title： Research on DC Interruption Technology-Topology and Its Key Technologies
Abstract: The DC circuit breaker is an indispensable device for constructing the DC grid and ensuring the reliability and flexibility of the DC power supply. Although the existing DC interruption technology has achieved staged research results, there are still problems such as high cost, large volume, and complicated control, which is difficult to meet the needs of large-scale application of DC grids in the future and becomes a bottleneck restricting the development DC grid. Therefore, it is necessary to fundamentally change the interruption principles of existing DC circuit breakers, and seek high-performance, low-cost, and miniaturized new technologies and methods. In view of the above problems, a novel topology of economical DC circuit breaker based on vacuum arc control is studied. The arc voltage can be rapidly increased by regulating the vacuum arc with a magnetic field, which can be used to commutate the current in the main branch fast. Firstly, the principle of arc control and the method of increasing arc voltage are introduced, and the key influencing factors affecting arc voltage and post-arc dielectric recovery are obtained. Secondly, the arc control method and its effect on commutation is analyzed, in which the specific design parameters are obtained. Finally, a series of DC circuit breaker prototypes are developed and applied to several DC power distribution demonstration projects.