气吹作用对CO2、CO2/C4-PFN、CO2/C5-PFK混合气体燃弧特性的影响

CO2及其混合气体在替代SF6方面已表现出较大的应用潜力,研究其燃弧特性对于新型断路器的研发具有重要意义。为此设计了模拟直动式和压气式高压负荷开关的燃弧过程的实验装置,搭建了多参量综合测量的实验平台,针对CO2及其与C4–PFN、C5–PFK混合气体在拉弧以及喷口限制吹弧条件下的燃弧特性开展了实验研究,对燃弧过程中的电弧电压、电弧电流以及电流过零附近的零区特性进行了测量,并利用Mayr电弧模型,对比了不同燃弧实验中CO2及其与C4–PFN、C5–PFK混合气体的弧后击穿特性。研究发现:气吹作用对于小电流期间电弧的能量耗散有着极强的促进作用;在拉弧实验中,CO2气体的热开断性能大约为SF6的50%,C5–PFK–CO2混合气体的热开断性能约为SF6的75%,而C4–PFN–CO2混合气体则与SF6的热开断性能相当;在吹弧实验中,CO2、C5–PFK–CO2和C4–PFN–CO2混合气体的热开断能力分别大约为SF6的45%、68%和91%。

Effects of Air-blowing on the Arcing Characteristics of CO and CO/C4 PFN,CO/C5 PFK Mixtures

CO2 and its mixtures have already considered as potential substitutes for SF6, so it is interesting to investigate their arcing characteristics used for new type circuit breakers. In this paper, an experimental device for simulating the arcing process of direct action type and puffer type high-voltage load switches was designed. An experimental platform for multi-parameter comprehensive measurement was built. The experimental research was carried out on the arcing characteristics of CO2 and its mixtures with C4–PFN or C5–PFK, with stretching arc as well as nozzle-limited stretching arc under gas flow. The arc voltage, arc current, and current zero characteristics near the current zero were measured. Moreover, the Mayr arc model was applied to compare the post-arc breakdown characteristics of CO2 and its mixed gas with C4–PFN or C5–PFK under different arcing modes. It is found that the air blowing effect has a strong promotion effect on the energy dissipation of arc during the small current period. In the arcing experiment, the thermal interruption capability of CO2 gas is about 50% of SF6. The thermal interruption capability of C5–PFK–CO2 mixed gas is about 75% of SF6, and the C4–PFN–CO2 mixed gas has almost equal thermal interruption capability to SF6. In the air-blowing arc experiment, the thermal interruption capability of CO2, C5–PFK–CO2 and C4–PFN–CO2 mixed gas was about 45%, 68% and 91% of SF6, respectively.