真空開閉器によるケーブル回路の進み小電流遮断時における三相同時遮断の数値解析

抄録

Three-phase simultaneous interruption will occurs in breaking low current by vacuum switch in a cable circuit. High surge voltages caused by multiple-reignition following three-phase simultaneous interruption will appear between the contacts and the terminals of the source transformer.
This paper presents the investigation on three-phase simultaneous interruption phenomena in breaking low capacitive current by vacuum switch in a cable circuit. Voltages across the contacts and the terminals of the source transformer, and the currents flowing through the gaps are measured experimentally and calculated by the electromagnetic transients program (EMTP). As a arc model, Mayr type arc equation is used to calculate the high frequency arc currents and arc voltages of the vacuum switches, and good agreement between the calculation and the experimental results have been achieved. The domain of the occurrence of the three-phase simultaneous interruption concerning with current chopping, load current, cable length and insulation characteristic of the gaps is investigated by analysis.