A simulation analysis and an experiment are carried out to investigate how the gap difference between the breaks of a direct current vacuum circuit breakers with multi-breaks (MB-DC VCB) caused by the mechanism dispersion of the breaker influences the distribution of TRV among the breaks. An interruption model of MB-DC VCB, combining the continuous transition model, is established to analyse the rising rate of transient recovery voltage and the dielectric strength recovery speed of the breaks for MB-DC VCB under different gap difference conditions. Based on the experimental platform of dual break DC vacuum circuit breaker breaking, the correctness of the simulation model is verified on a DC VCB with the double-breaks interruption experimental platform. Moreover, a model is applied to the non-synchronous interruption simulation of a DC VCB with three-breaks. The relationship between the TRVs of the breaks under different gap difference conditions is analysed using the comparative analysis method, obtaining the maximum gap difference at the moment of breaking failure. The results of this study show that large-gap breaks have a higher TRV than small-gap breaks (the fracture of the action delay module), with double fractures reaching 1.4 times and triple fractures reaching a maximum of 1.52 times; the ability of small-gap breaks to withstand TRV is weak, giving rise to re-breakdown or even interruption failure; as the number of fractures increases, the maximum gap difference also increases. Improving the synchronous interruption ability of the MB-DC VCB is conducive to improving the interruption performance and interruption success rate of this type of a circuit breaker.

中文翻译：

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机构分散对组合式直流真空断路器暂态恢复电压分布的影响研究

通过仿真分析和实验研究了多断口直流真空断路器(MB-DC VCB)因断路器机构分散而引起的断口间隙差对TRV在各断口间分布的影响。休息。结合连续过渡模型建立了MB-DC VCB断口模型，分析了不同间隙差条件下MB-DC VCB断口瞬态恢复电压上升速率和绝缘强度恢复速度。基于双断口直流真空断路器分断实验平台，在直流真空断路器上利用双断口开断实验平台验证了仿真模型的正确性。并建立了模型对三断口直流真空断路器的非同步中断仿真。采用比较分析方法，分析不同间隙差条件下断裂TRV之间的关系，得到断裂破坏瞬间的最大间隙差。本研究结果表明，大间隙断裂比小间隙断裂（动作延迟模块的断裂）具有更高的TRV，双断裂达到1.4倍，三断裂最高达到1.52倍；小间隙断口承受TRV的能力较弱，导致重新击穿甚至中断失效；随着裂缝数量的增加，最大间隙差也增加。提高MB-DC真空断路器的同步开断能力，有利于提高该类断路器的开断性能和开断成功率。