Snubber Branch Design and Development of Solid-State DC Circuit Breaker
Xin Yan, Zhanqing Yu, Lu Qu, Zhizheng Gan, Chunpin Ren, Jinpeng Wu, Jiapeng Liu, Rong Zeng, Yulong Huang
Abstract
This research proposes a solid-state dc circuit breaker for low voltage dc system based on reverse-blocking integrated gate-commutated thyristor (IGCT). The circuit breaker topology gets easier as a result of reverse-blocking IGCTs’ ability to withstand reverse voltage. To further enhance the breaking process, we develop a snubber branch with metal oxide varistors (MOVs) and capacitance. The advantages and disadvantages of three distinct snubber branches—the no-snubber, the resistance–capacitance ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">RC</i> ), and the MOV-C snubber branch—are then contrasted. In addition to suppressing high-frequency oscillation caught by the parasitic MOV parameters, the structure with MOV-C snubber branch also blocks low-frequency harmonics brought on by <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">RC</i> snubber branch. Moreover, this structure can slow down the rate at which the voltage rises during the breaking process. Comparatively speaking to the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">RC</i> snubber branch and no-snubber branch structures, it is more appropriate for solid-state dc circuit breakers. Finally, a solid-state dc circuit breaker prototype based on RB-IGCT and MOV-C branch has been created. The maximum overvoltage is 1.5 kV and the rated voltage is 750 V. The maximum breaking current is 10 kA and the rated current can be 2 kA.