特高压断路器开断试验回路用球隙开关

Ball Gap Switch for Breaking Test Circuit of UHV Circuit Breaker

文中针对特高压断路器试验回路设计了一种具有光触发能力的球隙开关,阐述了这种球隙开关的技术方案和原理,并且分析了影响球隙开关性能的几个重要因素。根据球隙的结构特点进行了电场有限元近似计算和分析,确定了在不同的间隙下开关的自放电临界电压以及触发放电临界电压等关键参数,从而为球隙开关应用于不同的额定电压下的间隙选择以及触发电压选择等提供了依据。最后研制了球隙开关的样机,通过现场自放电和触发放电试验证明了文中的分析是基本正确的,所提的设计方案是可行的。

In this paper, a light-triggered ball gap switch is proposed for the test circuit of UHV circuit breaker. The technical scheme and principle of the switch are discussed. Meanwhile, several key factors, which affect the perforrnanee of the ball gap switch, are analyzed. By means of the finite element method, the electric field across the ball gap of the switch is calculated and estimated, so as to determine the minimum breakdown voltage distance in cases of the self discharge and the trigger discharge with different gap. The basis of gap selection and the trigger voltage selection are provided for the ball gap switch with different rated voltage. Finally, a prototype of the ball gap switch is developed, the self discharge and trigger discharge tests are carried out. The results show the theoretical analysis offered in the paper are accurate to some extent, and the design idea of the ball gap switch is feasible.