433 / 2017-04-27 21:29:48

Research of Grading for Series-connected Thyristor Valves of Solid-state Transfer Switch

13706,13707,13708,13709

Abstract- The solid-state transfer switch is composed of thyristor valves and vacuum switches in parallel,and thyristor valve series grading is one of important technologies to ensure the normal operation of solid-state transfer switch.Based on the study of static blocking and dynamic switching characteristics of series-connected thyristor and the mathematic model for thyristors ,the main causes of voltage unbalance between series-connected thyristor valves are found. And the grading scheme for series-connected thyristorsss valves is that using parallel R branch for static grading and parallel RC snubbers branch for dynamic grading.The simulation analysis is carried out by using saber software .The results show that the grading scheme is validity and parameter setting for grading is accuracy .Finally, it is demonstrated by experiments that the proposed scheme can effectively suppress the overvoltage between the series-connected thyristor valves .