基于抑制起弧原理的中压无弧直流断路器

直流断路器是多端直流输电和直流配电网的关键设备。机械式和混合式直流断路器面临的困难是开断过程中触头间存在燃弧问题。文中讨论了产生电弧的电场强度和电压条件,并通过大量实验统计分析,总结出了抑制起弧所需满足的电场强度和电压条件。设计了抑制起弧的辅助缓冲电路,用以限制开断过程中触头间电压的上升,使其低于由机械开关速度决定的触头间介质绝缘电压,从而实现了直流断路器的无弧开断。通过仿真和低压模拟实验验证了抑制起弧原理和缓冲电路设计的正确性和有效性,并分析了中压无弧直流断路器的可行性。

Medium-voltage Arcless DC Circuit Breaker Based on Arc Suppression

DC circuit breakers serve as a key device for multi-terminal DC transmission and DC distribution networks. The difficulties of mechanical and hybrid DC circuit breakers are arcs between the contacts of mechanical switches during the breaking process. This paper discusses the electric field intensity and voltage conditions for arcs. By statistical analysis of a large number of experiments, the electric field intensity and voltage conditions to be met for arc suppression are summarized. An auxiliary buffer circuit for arc suppression is designed to limit the voltage rise between the contacts during breaking. This makes the voltage lower than the medium isolation voltage between the contacts determined by the speed of mechanical switches, so that DC circuit breakers can break without arcs. The correctness and effectiveness of the arc suppression principle and buffer circuit design are verified by simulations and low-voltage simulation experiments, and the feasibility of a medium-voltage arcless DC circuit breaker is analyzed.