石墨电极气体开关的脉冲电弧冲击力及其抵御结构研究

为提高吉瓦-百千安-高di/dt脉冲电弧放电条件下石墨电极气体开关的通流能力和结构可靠性，本项目拟依托本单位大电流脉冲放电开关试验平台，采用理论分析和实验研究相结合的方法，研究石墨电极气体开关的脉冲大电流电弧冲击力作用机制及抵抗强冲击力避免破坏的新型结构。本项目将研究开关脉冲电弧电流引起的洛伦兹力、气体热膨胀力、电弧激波冲击力的产生、发展与传播规律，分析揭示典型石墨电极和相应结构件的受力分布规律，建立受力极值与脉冲放电参数之间的数学物理模型；通过学习啄木鸟头部抗冲击结构，结合石墨材料特性，采取仿生学设计，提出满足应力分散传递的电极优化形制及抱箍式电极固定安装结构，理论计算和实验验证新型电极形状、固定方式、缓冲结构的优化设计方法，减小开关关键部件局部受力压强，提高在高电流峰值和高di/dt下的石墨电极受力安全性和开关整体的结构稳定性。本项目可为高性能石墨电极开关的研究提供理论支持。

In order to improve the discharge capability and structural reliability of the gas switch with graphite electrodes for high pulse current, high power and high di/dt, based on the pulsed switch test platform, this project will study the action-mechanism of shock force caused by discharge arc, and develop the switch structure with higher strength to prevent pressure failure. Specifically, the thermal expansion force, the Lorentz force, and arc shock force during switch discharge will be investigated. The focuses are the laws of generation, development and propagation of these forces. The force distributions of graphite electrodes and corresponding structural parts will be analyzed. The mathematical model between the pressure maximum and the pulse discharge parameters will be built. According to the bionics of woodpecker head and the graphite material properties, a novel electrode shape with large curvature side profile and its hoop mounting structure will be proposed. In this project, the optimal design theory of novel electrodes, fasteners and buffers will be quantified by theoretic calculation and experiments. Through these studies, the local pressure maximum applied to key parts of the switch will be decreased. While discharge with high current peak and high di/dt, the mechanical safety of graphite electrode and the overall structural stability of the switch will be improved. This project can provide theoretical supports to perfect the research of the high-performance gas switch with graphite electrodes.