Research on Application Technology of Sacrificial Bypass Thyristor Suitable for VSC-HVDC System

摘要

With the development of VSC-HVDC technology, the performance and application technology of bypass thyristors are constantly updated and improved. This paper studies a power electronic device that can effectively protect the VSC-HVDC system-sacrificial bypass thyristor, analyzes application methods and test results of gate current injection sacrificial thyristor and voltage breakdown sacrificial thyristor in the VSC-HVDC system. Through research, it is pointed out that the gate current injection sacrificial thyristor needs to add energy storage power source and requires a certain time for heat accumulation, which is currently less practical. The voltage breakdown sacrificial thyristor not only has the functions of forward conduction and reverse blocking, but also has the characteristics of reverse precise breakdown and great rupture resilience. The voltage breakdown sacrificial thyristor can realize comprehensive protection of MMC submodules, which has already been implemented in Rudong Project, and the prospect of subsequent application promotion is broad.