250 kV振荡波发生器的固态断路器均压环优化设计

固态断路器的极板边缘电场分布计算是实现安全裕度下断路器均压环优化设计的关键。应用有限元法将断路器内的典型结构简化成轴对称模型,可实现准确快速计算。对充电放电暂态变化过程的电路仿真,发现了放电过程中电场强度比充电过程电场强度更小。基于有限元方法,计算了电场分布,优化设计了均压环。引入均压环管径、外径、安装距等结构参数,提出二阶灵敏度系数的概念,研究了各参数对均压环表面及断路器极板边缘电场分布的影响,有效地将均压环表面的最大电场强度控制在2.5 kV/mm以下。得出了满足250 kV固态断路器均压环条件的有效优化方案。

Optimial Design of Grading Ring of Solid State Breaker for 250 kV Oscillating Wave Generator

The calculation of the electric field distribution along the plates of solid state breaker is the key to optimal design of the grading ring under a margin of safety. The typical structure in the breaker can be reduced to axisymmetric model by using the finite element method, which makes computation fast and accurate. The simulation results of the transient process show that the effect of the electric field intensity on electronic device is negligible. In this paper, we adopted the finite element method to calculate the electric field and optimize design of the grading rings. The structural parameters of grading rings for breaker, such as the ring radius, radius of the ring tube and mounting height, were introduced. A new concept of second-order sensitivity coefficient a is proposed to calculate the influences of different structural parameters of grading rings on potential and electric field distribution along the plates of solid state breaker, which effectively controlls the maximal electric field intensity below 2.5 kV/mm. The optimal configuration scheme of grading ring of 250 kV solid state breaker is proposed.